Scielo RSS <![CDATA[Archivos de Zootecnia]]> http://scielo.isciii.es/rss.php?pid=0004-059220110003&lang=en vol. 60 num. 231 lang. en <![CDATA[SciELO Logo]]> http://scielo.isciii.es/img/en/fbpelogp.gif http://scielo.isciii.es <![CDATA[<b>Brief notes on the history of the iberian societies for the animal genetic resources</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300001&lng=en&nrm=iso&tlng=en Los recursos zoogenéticos son esenciales en la adaptación a las condiciones socioeconómicas y ambientales cambiantes de cada zona, incluido el cambio climático. Son la materia prima del mejorador animal y se encuentran entre los insumos más esenciales del ganadero. Son fundamentales para la producción agrícola sostenible. Precisamente con esta filosofía nace en la Sociedad Española para los Recursos Genéticos Animales (SERGA) y la Sociedad Portuguesa de Recursos Genéticos Animais (SPREGA). Ambas tienen como objetivos fundamentalmente el conocimiento, estudio, protección, conservación y promoción de los recursos genéticos animales en general y ganaderos en particular, existentes en España y Portugal.<hr/>Zoogenetic resources are essential in the adaptation to the socioeconomical and environmental conditions permanently in change in every area, including the climatic change. These are the primary material in animal improvement and they are found in between the essential input of farmers. They are fundamental for the sustainable agriculture production. Precisely with this philosophy the Spanish Society on Animal Genetic Resources (SERGA) and the Portuguese Society on Animal Genetic Resources were born. Both have the main objectives the knowledge, the study, the protection, the conservation and the promotion of the animal genetic resources in general, and the farm animals genetic particularly, both existing in Spain and Portugal. <![CDATA[<b>Analysis of reproductive characteristics indicators of puberty in young Pantaneiro bulls</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300002&lng=en&nrm=iso&tlng=en Descendentes de animais oriundos da Península Ibérica, os bovinos Pantaneiros foram introduzidos no Brasil na época do descobrimento. Características reprodutivas foram monitoradas em dez tourinhos, no intervalo de idade de dez a vinte meses, criados em pastagens nas condições de Brasil central com objetivo de determinar a idade à puberdade. Mensalmente eram mensuradas a circunferência, o comprimento e a largura testicular. O sêmen foi coletado e os aspectos de morfologia e físicos do ejaculado avaliado. Foi avaliada a idade do desprendimento entre pênis e prepúcio, do aparecimento da primeira célula espermática, da primeira célula espermática móvel e da puberdade seminal.<hr/>The Pantaneiro cattle are descendant from animals brought by settlers in the beginning of the colonization of Brazil. Ten months old Pantaneiro steers, raised under pasture conditions in Brazil, were used to study puberty. Monhtly measurement of scrotal circumference and testicular width and length were recorded. Semen was collected by eletroejaculation and evaluated according to physical and morphological aspects. Penile and prepuce detachment percentages were also evaluated. The ages of first spermatozoa presence in the ejaculate, first motile spermatozoa in the ejaculate, seminal puberty and detachment between penis and prepuce was studied. <![CDATA[<b>Growth of Mos chickens in various seasons of the year</b>: <b>comparison with an industrial chicken strain</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300003&lng=en&nrm=iso&tlng=en En el presente trabajo se estudian los crecimientos y el consumo alimenticio de los machos de la raza Galiña de Mos hasta alcanzar el denominado peso vivo comercial mínimo, estipulado por numerosos autores y el mercado en torno a los 2,1 kg de peso, en dos estaciones diferentes del año, invierno y primavera, y comparándolos con una de las estirpes de pollo rubio más utilizadas en Galicia, el Sasso T-44. Para ello se criaron en el Centro de Recursos Zooxenéticos de Galicia en régimen extensivo, 130 pollitos machos sexados de T-44 y 400 pollitos Mos sin sexar hasta las 4 semanas de edad, momento en el que se separaron los machos para realizar el estudio. A la vista de los resultados obtenidos se pudo observar un consumo alimenticio sensiblemente superior tanto en la raza autóctona como en el híbrido industrial, en los lotes criados en invierno frente a los de primavera, debido a la influencia de las diferentes temperaturas observadas. No se encontraron grandes diferencias en la edad en la que se alcanzaron los 2,1 kg de peso, ya que los Mos la alcanzaron a los 87 y 89 días en primavera e invierno respectivamente y a los 68 y 70 días en los T-44.<hr/>In this work we study the growth and feed intake of male Galiña de Mos breed to reach the socalled minimal commercial weight stipulated by many authors and the market at around 2.1 kg weight, in two different seasons of the year, winter and spring, compared with a blonde chicken strain commonly used in Galicia, Sasso T-44. A hundred and thirty male, sexed, chicken T-44 and 400 Mos chicken unsexed (until to 4 weeks of age, when males were separated for the study) were raised in the Centro de Recursos Zooxenéticos de Galicia under extensive conditions. It was observed a significantly higher feed intake, both in the native breed and the industrial hybrids, in chicken reared in winter compared to those of spring, due to the influence of different temperatures observed. There were no major differences in the age at which reached 2.1 kg weight, since Mos's reached the 87 and 89 days in spring and winter respectively and 68 and 70 days in the T-44. <![CDATA[<b><i>Post-mortem</i></b><b> tenderization of beef from different biotypes included in the PGI Ternera Asturiana</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300004&lng=en&nrm=iso&tlng=en Se estudió la actividad de la μ-calpaína y la tenderización a lo largo de la maduración postmortem (de 2 h a 21 d) en carne procedente de distintos biotipos amparados por la Indicación Geográfica Protegida (IGP) Ternera Asturiana, según la raza (Asturiana de los Valles, AV y Asturiana de la Montaña, AM) y el genotipo para la mutación en el gen de la miostatina causante de la hipertrofia muscular (mh/mh, mh/+, +/+). Esta mutación produjo diferencias significativas en la evolución post-mortem de la calidad de la carne promoviendo un descenso más rápido del pH y una activación más temprana de las calpaínas y por tanto de la proteolisis en los biotipos AV (mh/mh y mh/+) que mostraron un ritmo de tenderización más temprano que la carne de los biotipos normales (+/+) de ambas razas. Los resultados indican que las diferencias encontradas entre biotipos en pH y actividad de μ-calpaína muestran un paralelismo con el proceso de tenderización.<hr/>Tenderization and μ-calpain activity were studied along post-mortem maduration (2 h to 21 d) on beef from different biotypes included in the Protected Geographical Indication (PGI) Ternera Asturiana attending to breed (Asturiana de los Valles, AV and Asturiana de la Montaña, AM) and genotype for myostatine mutation causing muscular hypertrophy (mh/mh, mh/+ and +/+). This mutation produced significant differences in meat quality, promoting a faster pH decline and earlier activation of calpains, which resulted in faster proteolysis in AV(mh/mh andmh/+) biotypes, that showed earlier tenderization rate than normal (+/+) biotypes of both breeds. The results showed that differences among biotypes in pH and μcalpain activity paralleled the tenderization process. <![CDATA[<b>Analysis of preweaning growth traits in Gochu Asturcelta piglets</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300005&lng=en&nrm=iso&tlng=en Para caracterizar el crecimiento de lechones de raza Gochu Asturcelta en la primera fase de crecimiento, se estudiaron 191 pesos al nacimiento y 146 al destete registrados a partir de 23 partos de 12 hembras en el Núcleo de Multiplicación del Servicio Regional de Investigación y Desarrollo Agroalimentario de Asturias (SERIDA). El peso medio fue, al nacimiento de 1439 ± 279 g, y al destete de 12,840 ± 3,055 kg, a una edad promedio de 42 días y la ganancia media diaria predestete de 268 ± 0,061 g. Los modelos lineales ajustados para el análisis de los factores ambientales de mayor importancia para la determinación de esos caracteres informaron de que ni el sexo, ni la viabilidad a las 48 horas de vida, ni el número de camada afectaron significativamente al peso al nacimiento de los lechones (p>0,05). Los efectos número de camada (p= 0,049) y edad al parto de la madre (p= 0,014) influyeron significativamente en el peso al destete. El peso al destete de los lechones de tercer parto fue significativamente superior al de los de primer parto (1,100 kg). Los efectos del número de camada, edad al parto de la madre y edad al destete del lechón influyeron significativamente en la ganancia media diaria predestete; sin embargo este carácter no se vió influido por el efecto del sexo del lechón (p= 0,68). Las camadas de tercer parto crecieron 34 g/día más que las camadas de primer parto. El presente estudio supone el primer intento de caracterización de la capacidad productiva del Gochu Asturcelta.<hr/>The aim of the present study is the caracterization of the growth of Gochu Asturcelta piglets. In this first approach we studied 191 born weights and 146 weaning weights from 12 sows located in the Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA). The average birth weigth was 1439 ± 279 g, the weaning weigth 12.840 ± 3.055 kg with a weaning age of 42 days and a preweaning daily gain of 268 ± 0.061 g/day. The lineal models adjusted for the analysis of the environmental factors of higher significance for the characters under study showed that the birth weight is not affected by piglet sex, 48 h piglet survival or litter number (p>0.05). The weaning weigth was significantly affected by litter number (p= 0.046) and sow age at birth (p= 0.014). The weaning weight of third birth piglets were significantly higher to the first birth. The preweaning daily gain was significantly affected by litter number, age of the sow at birth and weaning age. The weaning weight was not affected by piglet sex (p= 0.68). The third litter growth 34 g/day faster than first birth litter. The present study is the first approach to the characterization of the production ability of Gochu Asturcelta breed. <![CDATA[<b>Demographic analysis of the equine breed Spanish-Arabic</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300006&lng=en&nrm=iso&tlng=en El esquema de selección del caballo Hispano-Árabe se encuentra en desarrollo por lo que es necesario conocer su estructura poblacional a partir de la información registrada en el Libro Genealógico para diseñar una estrategia de mejora y utilización. Se calcularon los parámetros demográficos, sobre un censo total de 1041 animales que forman parte del núcleo selectivo de la raza. El tamaño efectivo obtenido fue de 1036,94 animales (553 hembras y 488 machos), con un ratio sexual de 1,13.Si el manejo reproductivo es el correcto, habría un incremento de la endogamia por generación de 0,000482 (0,048%) y por año, de 0,000055 (0,005%), algo esperado debido al intervalo generacional total de 8,65 años (hembras 8,95 y machos 8,31). El valor obtenido fue alto pero común en la especie equina, donde muchos animales se utilizan sólo para carreras deportivas. La tasa de reposición observada en hembras fue de 12,66% y en machos, de 11,68%, con una edad media para machos y hembras de 8 y 9 años, respectivamente. Se deduce que el progreso genético se está gestionando de manera adecuada, manteniendo la variabilidad genética y dinámica de la raza.<hr/>The breeding program of the Spanish-Arabian horse is in process of development and, for this reason, is necessary to know its population structure from the information registered in the Herd Book to design strategy for its improvement and utilization. The demographic parameters were calculated having a census of 1041 animals, taking part of the selective nucleus; the effective population size was 1036.94 (553 females and 488 males) with a sex ratio of 1.13. With a correct reproductive management we expect an increasing of the inbreeding rate by generation of 0.000482 (0.048%) and by year of 0.000055 (0.005%), something expected because the total generational interval of 8.65 years (females 8.95 and males 8.31), value too high in the equine species, but common, because of a lot of animals are employed only in sport activities. The level of replacement observed was 12.66% in females and 11.68% in males, with mean ages of 8 and 9 years in males and females respectively. The good management of the genetic progress is demonstrated, also maintaining the level of genetic variability and dynamism of the breed. <![CDATA[<b>Study of sperm parameters in the Retuertas Horse</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300007&lng=en&nrm=iso&tlng=en La concentración geográfica y el reducido censo del Caballo de las Retuertas obligaron a diseñar un plan de conservación integral. Una de las herramientas para la conservación ex situ fue la creación de un banco de germoplasma. Previamente, se estudió la calidad seminal y aptitud para congelación. Los resultados obtenidos fueron: volumen 23,25±12,72 ml, concentración 335,83±135,60x10(6) espermatozoides/ml; motilidad masal 3,83±0,98 (1-5) y motilidad progresiva 60,42±15,42 (0-100%), mostrando todas diferencias significativas en relación al semental.<hr/>Geographical concentration and scarce census of the Retuertas horse force to design a complete conservation plan. One of the used tools as a mean of ex situ conservation was the creation of a germplasm bank. Previously, a study of the seminal quality and its aptitude for freezing was developed. Results were: volume 23.25±12.72 ml; concentration 335.83±135.60x10(6) spermatozoa/ ml; basal motility 3.83±0.98 (1-5) and progressive motility 60.42±15.42 (0-100%); all of them shown significant differences among stallions. <![CDATA[<b>Seminal characterization of the Menorquina sheep</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300008&lng=en&nrm=iso&tlng=en La oveja Menorquina está incluida en el grupo de razas en peligro de extinción según el Catálogo Oficial de Razas de Ganado de España. En el año 2003 estaban inscritos en el Libro Genealógico unos 2000 animales pertenecientes a 52 ganaderías. Actualmente, la raza cuenta, dentro del Programa de Conservación ex situ, con un banco de germoplasma que comenzó en 2008 y sigue completándose anualmente. Este trabajo expone los primeros resultados de la caracterización seminal del morueco de raza ovina Menorquina, en el que se ha estudiado el efecto de variables tales como volumen y concentración seminal, así como la motilidad masal y progresiva, en relación al año de la extracción seminal. En total se analizaron 41 eyaculados de 8 sementales. Los datos preliminares ofrecieron las siguientes medias y desviaciones típicas: concentración, 3 897x10(6)±2,74 espermatozoides/ml; 4 456x10(6)±4,43 espermatozoides totales; motilidad progresiva 50±16,77 (0-100%); volumen 1,06±0,66 ml; motilidad masal 3,58±1,01 (1-5). Todas las variables mostraron diferencias significativas en relación al año.<hr/>Menorquina sheep is included in the group of breeds in danger of extinction according the Offcial Spanish Catalogue of Livestock Breeds. In 2003, 2000 animals were enclosed in the herd book, all them belonging to 52 farms. Presently, the breed has, in the ex situ conservation program, a germplasm bank which started in 2008 and continues completing yearly. This paper exposes the preliminary results of the semen characterization of the Menorquina sheep breed male, studying variables such as volume, concentration, basal and progressive motility, in relation to the year of collection. A total of 41 ejaculates from 8 males were studied. Preliminary data offered the following means and standard deviations: concentration, 3 897x10(6)±2,74 espermatozoa/ml; 4 456x10(6)±4,43 total spermatozoa; progressive motility 50±16,77 (0-100%); volume 1,06±0,66 ml; basal motility 3,58±1,01 (1-5). The variables shown differences statistically significant among years of collection. <![CDATA[<b>Situation of three autochthonous Spanish races of the sheep species in Castilla y León</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300009&lng=en&nrm=iso&tlng=en En tres razas autóctonas españolas (Churra, Castellana y Ojalada) se estudió la situación censal, incluyendo su orientación productiva, tanto de explotaciones como de animales, así como su participación en dos denominaciones de calidad y la inscripción en sus libros genealógicos. Los mayores censos de animales correspondieron a la raza Churra seguidos de la Castellana, en ambas con predominio de los rebaños de orientación carne; a mucha mayor distancia se encontraron los de la Ojalada. La inscripción de explotaciones en la DO Queso Zamorano, a tenor de su orientación productiva, fue prácticamente total para el caso de la raza Castellana. Para la IGP Lechazo de Castilla y León el número de explotaciones inscritas en la misma fue bajo, excepto en la raza Ojalada. Las inscripciones en los libros genealógicos resultaron muy bajas, a excepción de la raza Ojalada.<hr/>In three autochthonous spanish races (Churra, Castellana and Ojalada) studied the sensual situation, including his productive orientation, both of developments and of animals, as well as his participation in two denominations of quality and the inscription in his genealogical books. The major censuses of animals corresponded to the race Churra followed by the Castellana, in both with predominance of the flocks of orientation meat; to many major distance those of the Ojalada were. The inscription of developments in the DO Queso Zamorano, to tenor of his productive orientation, was practically total for the case of the Castellana race. For the IGP Lechazo de Castilla y León the number of developments inscribed in the same one was low, except in the race Ojalada. The inscriptions in the genealogical books turned out to be very low, with the exception of the race Ojalada. <![CDATA[<b>Geographical indication in conservation and value aggregation to Curraleiro cattle of the Kalunga community</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300010&lng=en&nrm=iso&tlng=en Este trabalho objetivou mostrar a importância das indicações geográficas, como estratégia de conservação e agregação de valor ao gado Curraleiro e, propor estratégias para o futuro registro da denominação de origem Carne de Curraleiro Kalunga, pela comunidade remanescente de quilombo Kalunga do município de Cavalcante, Goiás, Brasil. O reconhecimento da denominação de origem Carne de Curraleiro Kalunga, viabilizará o estabelecimento de uma modalidade de exploração sustentável para o Cerrado, com a preservação de uma raça bovina adaptada as condições adversas deste bioma e proporcionará às famílias quilombolas, melhoria na disponibilidade de alimento e aumento da renda familiar.<hr/>The objective of this study was to show the importance of geographical indications, as a strategy of maintaining and aggregating value to the Curraleiro cattle, and as a basis for future registration of the denomination of origin Kalunga Meat of Curraleiro, by the remaining Kalunga quilombo community in Cavalcante situated in the State of Goiás, Brazil. Recognition of the denomination of origin Kalunga Meat of Curraleiro, will make establishment of a modality of sustainable exploration in the Cerrado possible, as well as promote preservation of a bovine race well adapted to adverse conditions of this biome, improve their food availability and increase family income. <![CDATA[<b>Principal component analysis for type traits in males of Celta pig breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300011&lng=en&nrm=iso&tlng=en La Asociación de Criadores de la Raza Porcina Celta (ASOPORCEL), que trabaja en la recuperación y conservación de la raza porcina Celta, realiza un sistema de calificación morfológica de los animales que forman parte de su Libro Genealógico. En este estudio se determina el grado de relación existente entre las variables que componen dicho sistema para los machos reproductores de la Raza Porcina Celta mediante un análisis de componentes principales. Los caracteres morfológicos empleados fueron: aspecto general; piel, pelo y pigmentación; cabeza; pescuezo y tórax; espaldas; dorso y lomos; jamones; testículos; aplomos y extremidades. Todas las correlaciones resultaron positivas y en general moderadas. Los cuatro primeros componentes principales explicaron el 80% de la variación total. El primer factor está relacionado con el tamaño general del animal y el segundo con la piel, pelo y pigmentación. El sistema permite explicar las correlaciones entre cada una de las características analizadas haciendo posible su interpretación, si bien sería necesario ampliar el estudio para diferenciar las distintas variedades de la raza admitidas en su Libro Genealógico.<hr/>Celta Pig Breeders Association (ASOPORCEL) has introduced a linear type classification system for the classification of males. In this study the relation between the variables used in the qualification system is determined by means of principals components analysis. The used morphologic characters were: general aspect; skin, hair and pigmentation, head, neck and thorax; backs, ham, testicles, and extremities All the correlations were positive and generally moderate. The first four principal components explain 80%, of the variation. The first component represents general body size; the second with skin hair and pigmentation. The system explains the correlations between each one of the analyzed characteristics. It is necessary to extend the study to differentiate the different varieties of the breed in its Stud Book. <![CDATA[<b>Endangered Gochu Astur-Celta germplasm bank</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300012&lng=en&nrm=iso&tlng=en El objetivo de este trabajo fue el estudio de la posibilidad de criopreservar semen de verracos de la raza porcina autóctona Gochu Astur-Celta, que en la actualidad se encuentra en peligro de extinción, como herramienta en los planes de recuperación de la raza. Las dosis seminales obtenidas a partir de los eyaculados recogidos fueron envasadas, sometidas a congelación y posteriormente almacenadas en nitrógeno líquido, analizándose los siguientes parámetros: motilidad y calidad del movimiento, integridad funcional de la membrana, morfología y estado del acrosoma. Los resultados obtenidos muestran que es necesario seguir trabajando en la mejora de la calidad del semen congelado-descongelado para que esta técnica pueda contribuir a la conservación de la biodiversidad.<hr/>The use of sperm cryoconservation technique could help to the preservation of genetic material for long term. This work was carried out in order to develop preliminary studies regarding boar sperm cryopreservation in the autochthonous endagered pig breed Gochu Astur-Celta. The seminal doses obtained from ejaculates of these boars, were cryopreserved and then stored in liquid nitrogen. Semen analysis were carried out on every sample, and the parameters studied were: sperm motility, movement quality, normal apical ridge (NAR), morphology and functional membrane integrity (hyposmotic swelling test). The results showed that further studies are needed to improve the quality of frozen-thawed sperm to make this technique a useful tool in the field of biodiversity preservation. <![CDATA[<b>Structure and genetic relationships between Serrana de Teruel breed and other cattle breeds reared in Spain</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300013&lng=en&nrm=iso&tlng=en En este trabajo se analiza la variabilidad genética de la raza autóctona en peligro de extinción Serrana de Teruel, así como su relación con las razas bovinas explotadas en España: Albera, Pajuna, Avileña-Negra Ibérica, Serrana Negra, Pirenaica y Parda de Montaña. La caracterización genética se ha realizado mediante marcadores microsatélites, todos han resultado polimórficos detectándose un total de 198 alelos con una media de 6,79 alelos por locus. Las heterocigosidades observadas y esperadas fueron altas y similares en el equilibrio, con valores de 0,67 y 0,68 respectivamente. A partir del estudio de las relaciones filogenéticas se ha podido observar la cercanía de la raza Serrana de Teruel con las razas de montaña Pirenaica y Parda de Montaña. Mediante el estudio de la estructura genética se observó que el porcentaje de animales correctamente asignados a la Serrana de Teruel para q>0,8 fue del 47,5%, apreciándose una clara influencia de la raza Parda de Montaña en los individuos mezclados.<hr/>In this work we analyze by microsatellite markers the genetic diversity, structure and relationships of the indigenous endangered Serrana de Teruel cattle breed with different breeds reared in Spain. All loci were polymorphic and a total of 198 alleles were observed across loci, with a mean of 6.79. Observed and expected heterozygosities values shown the high variability of Serrana de Teruel breed with values of 0.67 and 0.68 respectively. The neighbour net based on Reynolds distances shown the close genetic relationship among Serrana de Teruel and the mountain Parda de Montaña and Pirenaica breeds. STRUCTURE results showed a 47.5% of correctly assigned individuals to Serrana de Teruel breed using a q>0.8 threshold. The admixed animals shown a clear influence of Parda de Montaña breed. <![CDATA[<b>Genetic characterization of South Spain boar</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300014&lng=en&nrm=iso&tlng=en El jabalí de interés cinegético en la península Ibérica, cuenta con numerosas sub-poblaciones de Sus scrofa mediterraneus. El Parque Nacional Doñana es la reserva biológica más importante de España y la mayor superficie protegida con gran diversidad ecológica distribuida en tres tipos básicos de ecosistemas: dunas, playas y marismas en los que cohabita gran variedad de mamíferos, aves, reptiles, peces.... entre los que se cuentan poblaciones de jabalí. Para conocer su diversidad genética, en comparación con otras poblaciones españolas, se han estudiado 25 marcadores microsatélites porcinos y se ha determinado la variación genética dentro y entre poblaciones mediante el análisis de la heterocigosis (0,53), número de alelos (5,60), desviación del equilibrio de HW y Fis (0,02).<hr/>The wild boar, a cinegetic species of Iberian Peninsula, has numerous sub-populations ofSus scrofa mediterraneus. Doñana National Park is the most important biological reserves in Spain and the largest protected area with great ecological diversity, distributed on three basic types of ecosystems: sand dunes, beaches and marshes. Here live together a variety of species: mammals, birds, reptiles, fishes... and, among them, the wild boar. In order to determine the genetic diversity, also in comparison with other Spanish populations, we studied 25 microsatellite pigs markers and found genetic variation within and among populations by analysis of heterozygosity (0.53), number of alleles (5.60), deviation by HW equilibrium and Fis index (0.02). <![CDATA[<b>Productive potential of the bovine breed Serrana de Teruel</b>: <b>Preliminary report</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300015&lng=en&nrm=iso&tlng=en En el marco de un proyecto de recuperación de la raza Serrana de Teruel, se estudió la calidad de la canal de las categorías comerciales de ternero, añojo y cebón (los últimos castrados con 9 meses), con edades a sacrificio de 12, 22 y 22 meses, y pesos vivos de 470, 720 y 660 kg, respectivamente. Veinte terneros se sometieron a cebo convencional con paja y concentrado a voluntad, desde los 4 meses hasta el sacrificio, excepto entre los 15 y 20 meses, en que añojos y cebones recibieron ensilado de cebada a voluntad y 3 kg concentrado/animal/día. El primer año de vida, la ganancia de peso de los terneros fue de 1,5 kg/día; el segundo año, fue superior en añojos que en cebones (1,1 vs. 0,9 kg/día), como consecuencia de la castración. Las canales de los animales enteros presentaron mayor rendimiento y conformación, y menor engrasamiento que las de los cebones ya que la castración favoreció la deposición de grasa intramuscular. Según los resultados, la raza se encuadró entre las rústicas bovinas españolas. Se abren alternativas de producción como el cebón, susceptibles de acogerse a distintivos de calidad diferenciada, que deberían suponer un incentivo para la explotación de la Serrana de Teruel frente a otras razas, lo que garantizaría su conservación a largo plazo.<hr/>The carcass quality from three commercial categories (yearling, bull and steer castrated at 9 months old) was studied within the framework of a recovery programme in the Serrana de Teruel breed. Ages at slaughter were 12, 22 and 22 months, and live-weights were 470, 720 and 660 kg, in yearling, bull and steer, respectively. Twenty calves were managed under a conventional feeding programme of ad libitum concentrate and straw from 4 months old to slaughter, except between 15 and 20 months old, in which bulls and steers received ad libitum barley silage as forage supplemented with 3 kg of concentrate/head/day. The gain during the first year of age was 1.5 kg/ day, whereas during the second year it was greater in bulls than in steers (1.1 vs. 0.9 kg/day), as a consequence of castration. Bull carcasses had greater dressing percentages and conformation scores and lower fatness degree than steers, confirming a castration-induced intramuscular fat deposition. Considering these results, Serrana de Teruel breed falls within the group of local Spanish bovine breeds. These studies should provide the conditions for a labelled beef product that allows the farmer's survival and the assurance of Serrana de Teruel breed conservation for a long term. <![CDATA[<b>Undertaken activities to recover and preserve the Churra Tensina sheep breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300016&lng=en&nrm=iso&tlng=en En el caso de la raza Churra Tensina, en peligro de extinción y originaria del Pirineo Oscense, se realizó una prospección de individuos y una caracterización del sistema productivo a través de encuestas a ganaderos, definiéndose explotaciones de mediano tamaño que tienen su continuidad garantizada. Se estudió la morfología racial a partir de medidas zoométricas y caracteres fanerópticos de los animales inscritos en la Asociación (ATURA), lo que permitió clasificar la raza como mediolínea, dolicocéfala y eumétrica. Se estudiaron los parámetros productivos y reproductivos, así como la calidad de canal y carne de los tipos de cordero lechal, ternasco y pastenco, confirmando su viabilidad comercial. La caracterización genética mostró una raza homogénea, con niveles altos de variabilidad genética y bajos de consanguinidad. Finalmente, se han creado bancos de semen y embriones, estando representados los distintos genotipos de resistencia a Scrapie. La evolución positiva del censo en los últimos 10 años, añadida a la viabilidad de sus productos comerciales, garantiza la preservación de la Churra Tensina y de determinados sistemas ganaderos ligados a la tierra.<hr/>This work aims to present the research activities in the Churra Tensina sheep breed, raised on the mountain area of Huesca Pyrenees. The population structure was prospected and the farming system was characterized through surveys to farmers. The animal morphology was studied through zoometric measurements and phaneroptic characters assessment of the individuals belonging to the breeders' Association (ATURA), showing a mediolineous, dolicocephalous and eumetric breed. The productive and reproductive parameters were analysed, and the commercial value of the suckling, light and heavy lamb categories was confirmed. The genetic studies showed that Churra Tensina is an homogeneous breed, with high genetic variability and low inbreeding. This breed was self-genetic differentiated, and has no crossbreeding with other Churro group populations. Finally, semen and embryos banks were established, being the different Scrapie resistance genotypes represented. The increasing census evolution in the past 10 years and the observed commercial viability assure the long term maintenance of this breed in their original location. <![CDATA[<b>Carcass quality of Galician Mountain foals</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300017&lng=en&nrm=iso&tlng=en Fueron estudiadas las características de la canal de 50 potros Gallego de Monte provenientes de tres explotaciones. El peso al sacrificio de los potros de diez meses de la explotación extensiva acabados con heno y pienso ecológico (SEC) fue superior (p<0,001) a los de la explotación extensiva, de un año, sin acabado (SE) (199 vs. 138 kg). El rendimiento canal también se vio afectado (53,35% vs. 49,48%, p<0,01). El porcentaje del cuarto delantero fue superior (p<0,001) en los animales criados en libertad (SEL, 39,59%) que en SE (38,66%) y SEC (35,76%). El porcentaje de magro y la grasa total fueron superiores en SEC (p<0,001).<hr/>The carcass characteristics of 50 Galician mountain foals from three different farms were studied. Slaughter weight was higher (p<0.001) in foals, ten months old, from SEC vs. SE a year old (199 vs. 138 kg). Dressing percentage was also affected (53.35% vs. 49.48%, p<0.01). The percentage of front quarter was higher (p<0.001) in SEL (39.59%) than SE (38.66%) and SEC (35.76%). Nevertheless, the lean percentage and total fat was significantly higher in SEC foals (73 vs. 69 p<0.05; 6.68 vs. 3.25, p<0.001). <![CDATA[<b>Meat quality of Galician Mountain foals from three different farms</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300018&lng=en&nrm=iso&tlng=en Se estudió la calidad de la carne del músculo Longissimus dorsi (LD) en 51 Potros Gallegos de Monte procedentes de tres explotaciones diferentes. El sistema de explotación afectó al contenido de humedad y proteína e índice de rojo (p<0,001), y también afectó al contenido de Fe-hemo y al índice de amarillo (p<0,01), aunque estas diferencias también pueden ser debidas a la distinta edad de sacrificio de los animales estudiados. En general, la carne fue muy magra (<1% en GIM) con un alto contenido de proteína (&gt;19,5%) y Fe-hemo (1,47 mg/100 g carne) comparado con la carne de ternera. Las muestras también mostraron una alta luminosidad (L*&gt;40) muy buena capacidad de retención de agua, medida a través de las pérdidas por cocción (<17.4%) y una terneza inferior a 4 kg, pudiéndose clasificar como muy tiernas.<hr/>The meat quality of Longissimus dorsi (LD) in a total of 51 Galician Mountain Foals from three diferent production systems was studied. The livestock production system affected significantly moisture and protein content and redness (p<0.001), also affected on heme-Fe content and yellowness (p<0.01), although these differences could be also at differences in slaughter aged of foals . In general, meat from foals of this study showed as a very lean meat (<1% in IMF) with a high protein content (&gt;19.5%) and heme-Fe (1.47 mg/100 g meat) comparable to veal meat. Also, meat samples showed, higher luminosity (L*&gt;40) very good water holding capacity, measured by cooking losses (<17.4%) and tenderness less than 4 kg, so can be classified as a meatvery tender. <![CDATA[<b>Herd book management in Catalan chicken breeds</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300019&lng=en&nrm=iso&tlng=en En el 2008 se crearon los Libros Genealógicos de las razas de gallinas catalanas cuya gestión lleva el IRTA. Para ello se utilizaron dos sistemas algo distintos según la Asociación de Criadores, los que damos a conocer dado que ambos permiten un control muy estricto del pedigrí, que como es sabido resulta difícil en aves. Los adultos inscritos en los Registros Fundacional, Definitivo o Auxiliar, en el momento de la reproducción, se individualizaron en baterías. El IRTA diseñó los apareamientos y reprodujo los individuos seleccionados mediante inseminación artificial. En el caso de la Asociación de la raza Prat, los criadores están centralizados en la zona de origen y los reproductores están en sus explotaciones desde el día de vida. En el momento de la reproducción se recogieron los huevos numerados, se transportaron al IRTA donde tuvo lugar el nacimiento, la identificación y la inscripción en el Registro de Nacimientos de los nuevos ejemplares. La cría posterior y la selección se realizaron en las explotaciones de los socios. En el momento actual figuran inscritos 175 machos y 461 hembras. En las Asociaciones de las razas Penedesenca y Empordanesa los socios que participan están muy dispersos. En este caso la cría, selección y reproducción se realizó en el IRTA. Una vez reproducidos los selectos, se suministraron a los criadores, los cuales continuaron con la conservación. Actualmente, en el libro de la raza Penedesenca figuran inscritos 204 machos y 420 hembras, mientras que en el de la Empordanesa hay 229 machos y 527 hembras.<hr/>In 2008 the herd books of Catalan chicken breeds were created and their management is conducted by IRTA. We present two different management systems which are being used depending on breeders associations; both allow us a strict control of the pedigree, it is well known that is difficult in birds. The adults registered in the Foundational, Definitive or Auxiliary Registers, at the moment of the reproduction, they were housed on individual cages. IRTA designed the matings and reproduced the selected birds by artificial insemination. In Prat breed Association, the partners are situated in the origin zone and the breeders are in the farms since the birth day. At the moment of the reproduction, the partners collected the numbered eggs and they were transported to IRTA where the birth, the identification and the register of the newborns in the Birth Register took place. The rearing and the selection were carrying out in the breeder's farms. In that moment there are 175 males and 461 females registered. In Penedesenca and Empordanesa breed Associations, the partners are widely dispersed. In this case rearing, selection and reproduction were carrying out in IRTA. When selected birds were reproduced, they were provided to the breeders who continued with the conservation. At present, in Penedesenca breed herd book there are 204 males and 420 females and in Empordanesa breed herd book there are 229 males and 527 females. <![CDATA[<b>First results in the study of the morphology present status of the Andalusian Black cattle breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300020&lng=en&nrm=iso&tlng=en La raza Negra Andaluza se encuentra en peligro de extinción tras haber estado al borde de la desaparición. Además de la actual situación de la ganadería española, a lo anterior ha contribuido su pertenencia al tronco Negro Ibérico, y la gran presión que razas con un potencial más desarrollado han ejercido sobre ésta. Se han comenzado los estudios necesarios para la conservación de este recurso genético, entre ellos, el estudio morfológico. Hasta el momento se han estudiado 3 ganaderías diferentes sin influencia genética de otras razas y un total de 24 hembras adultas en las que se han tomado 14 medidas morfológicas. Además se han observado variables cualitativas, como el perfil y la capa. Los individuos estudiados presentan poca variación morfológica entre ellos y, por tanto, acercan a la actualización del patrón morfológico de la raza.<hr/>Andalusian Black cattle breed is in danger of extinction alter to go out of the border of the disappearance. Moreover, the present situation of the Spanish farming, its belonging to theIberian Black branch, producing a high pressure from other related breeds with a better productive potentiality. Studies for the breed conservation have begun, among them, the morphological study. By the moment 3 different farms without known influences from other breeds and 24 adult females have been recorded for 14 quantitative morphological traits, and some qualitative such as front profile and coat colour. Studied individuals presented few morphological variation and it put the breed near of the breed morphological pattern updating. <![CDATA[<b>Genetic structure of the Tudanca bovine breed inferred from the genealogical information</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300021&lng=en&nrm=iso&tlng=en La información genealógica de la raza Tudanca disponible contiene animales nacidos entre 1966 y 2010 en 455 explotaciones. La caracterización del nivel de completitud de dicha información mostró un número medio de 2 generaciones completas equivalentes. Se calcularon los coeficientes de endogamia y de parentesco de cada individuo representado en el fichero de pedigrí, así como el número efectivo de fundadores, el de ancestros y el de genomas fundadores. Se calculó el censo efectivo de la población mediante la regresión de la endogamia sobre la cantidad de información genealógica, y también el de la última generación. A partir de estos parámetros se obtuvo la evolución de la pérdida de diversidad a medio plazo (50 años). Entre los animales con endogamia no nula el porcentaje de los que tienen valores elevados (>6,25) es muy elevado (87%), debido en gran medida al gran porcentaje de apareamientos entre animales muy emparentados (hermanos, padre-hijo). Los censos efectivos de genomas fundadores (72) y de ancestros (88) reflejan la base genética de la que proviene la población actual, mientras que la pérdida de variabilidad genética a medio plazo deducida del censo efectivo (18-29) muestra riesgo bajo o moderado.<hr/>The pedigree file of the Tudanca local bovine breed recovers information of animals born from 1966 to 2010 in 455 herds. The pedigree completeness level is characterised by a low number of equivalent complete generations (∼ 2). Individual inbreeding and relatedness coefficients, and effective number of founders, ancestors and founder genomes, were computed. Average effective population size was estimated based on the regression of the inbreeding on genealogical amount of information, and effective population seize for the last generation were also calculated. Using this information, medium-term inbreeding rate evolution (50 years) was predicted. A high percentage of animals (87%) with a high level of inbreeding (>6,25) was found. The effective number of founder genomes (72) and the effective number of ancestors (88) reflect the genetic base of the current population, while the medium-term loss of genetic variability predicted from the effective population size (18-29) showed a breed under a low to moderate level of genetic risk. <![CDATA[<b>Characterization of the Cantabric Water Dog</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300022&lng=en&nrm=iso&tlng=en El Perro de Agua del Cantábrico es una población ancestral, cuyos orígenes pueden ser comunes a los del Barbet, que se usaba en labores pesqueras. Morfológicamente se diferencia del estándar del Perro de Agua Español. Se usó la información proporcionada por 21 marcadores microsatélites en 21 muestras al azar de la población de Perro de Agua del Cantábrico, junto a 108 muestras de razas próximas (Perro de Agua Español, Portugués, Romagnol, Barbet y Caniche). Se calcularon los parámetros de diversidad genética, los estadísticos de Wright, y se analizó la existencia de una estructura genética subyaciendo a la información molecular utilizada. Genéticamente, resultó evidente la diferenciación con el resto de razas de agua próximas (F ST medio 0,13). El uso de reproductores dentro de la población ha dado lugar a una gran similitud genética, sin que se aprecie la existencia de subpoblaciones.<hr/>The canine breed Perro de Agua del Cantábrico is an ancestral population which probably share a common origin with the Barbet breed, and was used in fishing activities. Morphological traits in this breed are different from those in the Perro de Agua Español. We used the information provided by 21 microsatellite markers on 21 random individuals belonging to the Perro de Agua del Cantábrico and on 108 individuals belonging to other close related breeds (Perro de Agua Español, Portugues, Romagnol, Barbet and Caniche). Genetic diversity parameters and Wrigth statistics were calculated, and population structure on the basis of multilocus genotypes was investigated. A clear genetic differentiation of the Perro de Agua del Cantábrico breed from the rest of the breeds was detected (average F ST was 0.13). The reproductive isolation of this population has had other genetic consequences as the great genetic homogeneity without the existence of a sub-population structure. <![CDATA[<b>Farm structural characterization of the Pasiega local bovine breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300023&lng=en&nrm=iso&tlng=en La Pasiega ha sido recientemente reconocida como raza bovina en peligro de extinción por el MARM. El objetivo del trabajo fue la identificación de posibles dificultades para el desarrollo de estrategias de conservación mediante encuestas que permitieran conocer la estructura de las explotaciones. Las encuestas realizadas mostraron que el 86,7% son empresas familiares, 46,7% vive únicamente de los ingresos de la explotación, 93,3% agricultores a título principal, 73,3% mayor de 50 años, 33,3% tiene sucesor, el 42,22% explota la raza hace más de 50 años, y el 26,7% está integrado en Asociación de Defensa Sanitaria. El censo actual de la Pasiega es bajo, 359 animales, 5,6 animales/ganadero, y el 86,7% explota otras razas y especies animales. Extensión 40,5 ha/explotación, San Pedro del Romeral 54,3 ha/explotación. Terreno en propiedad 14,55%, comunal el 37,8%, en San Pedro Romeral el 57,4%. Se trata de una raza rústica explotada de forma tradicional desde hace décadas, en zonas de difícil orografía, con acusada pendiente, aprovechando los recursos naturales, por empresas familiares cuyo único ingreso es habitualmente el generado en la explotación, por venta de animales y no por producción láctea. Se alimentan en verano con pasto y en invierno con heno fundamentalmente, combinándolos en primavera y otoño. Localizada en grandes extensiones, repartidas en un elevado número de parcelas, siendo en escasas ocasiones propiedad del ganadero y constituidas en gran parte por pastos comunales, y alojadas en cabañas de piedra de escasas dimensiones.<hr/>The Pasiega cattle breed has been recently listed as endangered by the MARM (i.e. Spanish Ministry of Environment, Agriculture and Fisheries). The main objective of this study was to identify the potential difficulties in developing the Pasiega conservation strategy. To get information of the structure of the Pasiega farms, we performed co to the cattle raisers. The results showed that 86.7% were family farms. Forty-seven percent of farmers surveyed derived all their income from farming and 93.3% indicated that they earned the majority (i.e. 50% or more) of their income from agriculture. Seventy-three percent of farmers surveyed were older than 50 years, with 33.3% having a farm successor. Forty-two percent of farmers had got Pasiega cattle for more than 50 years and 26.7% were members of a health defence association. The population of Pasiega cattle is scarce accounting for 359 animals (i.e. mean= 5.6 head per farmer). Eighty-seven percent of farmers had other breeds and other species. The average size of farms was 40,5 ha, being slightly higher in San Pedro del Romeral (i.e. 54.3 ha/farm). Fifteen percent of the surface belonged to farmers with 37.8% being public grassland, this percentage was slightly higher in San Pedro Romeral (i.e. 57.4%). Our results showed that the Pasiega is a rustic breed which has been traditionally managed for decades. These cattle are able to range in very steep and rough terrain to forage the natural resources of the place. Usually the Pasiega farmers earn their income by selling the animals and no by dairy production. Feeding depends on grazing in summer and hay provisioning in winter, combining both systems in spring and autumn. The Pasiega cattle graze in large areas, with stone huts distributed in a lot of plots, and many of them are communal mountain grass. <![CDATA[<b>The production ability of the Pasiega bovine breed inferred from genes correlated with production traits</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300024&lng=en&nrm=iso&tlng=en Se utilizó la información molecular derivada de 27 polimorfismos localizados en 21 genes, asociados con caracteres económicos, como la producción de leche y su composición, el crecimiento muscular, veteado, terneza y jugosidad, o el color de la capa para evaluar las características productivas de la raza Pasiega. Cabe destacar: la presencia de los alelos B y E en el locus CSN3 que reflejan una buena aptitud quesera en esta raza; el predominio del alelo T en un polimorfismo del genRORC que está asociado con mayor veteado; y la posibilidad de seleccionar genotipos más favorables en genes como CAST y VIM (terneza), PPARG (tipo de ácido graso), AANAT, PGAm² o ME3 (características sensoriales) para mejorar la calidad de la carne.<hr/>We used molecular information from 27 polymorphisms located in 21 genes associated with economic traits as are milk production and its composition, growth, marbling, sensorial traits as are tenderness, juiciness, and coat colour useful for traceability, in order to evaluate production characteristics of the Pasiega breed. We found the presence of alleles B and E at the CSN3 locus which denote a good cheese ability; the predominance of allele T at theRORC locus associated with marbling and the possibility of selecting favourable genotypes at genes as CAST and VIM (for tenderness), PPARG (type of fatty acid), AANAT, PGAm² or ME3 (underlying sensorial traits) as a way to improve meat quality. <![CDATA[<b>Paternal genetic variability into the Lidia bovine breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300025&lng=en&nrm=iso&tlng=en El origen paterno en la raza bovina de Lidia se ha estudiado mediante el análisis de 6 microsatélites, un SNP y un Indel, localizados en el cromosoma Y, en un total de 603 machos pertenecientes a 33 encastes. Se han identificado 10 haplotipos con frecuencias entre 0,2% y 74%, todos clasificados dentro de los dos haplogrupos paternos previamente descritos en las razas bovinas domésticas europeas. De los 33 encastes, 25 presentaron un único haplotipo lo que justifica los bajos valores de diversidad haplotípica obtenidos. Sgún el análisis de varianza molecular, la mayor parte de la variabilidad genética se debe a las diferencias entre encastes (F ST= 82%). El análisis Network agrupó a los haplotipos pertenecientes al haplogrupo Y1 e Y2 en dos grupos claramente diferenciados.<hr/>A total of 603 males belonging to 33 lineages were genotyped for 6 micorsatellites, one SNP and one INDEL to clarify the paternal genetic diversity of the Lidia cattle breed. The number of haplotypes identifying were 10 with frequencies ranging between 0.2% to 74%. All the haplotypes belonging to the haplogropus previously defined in European domestic bovine breeds. In 25 of the 33 lineaes only one haplotype was identifying with low values of haplotypic diversity in all the lineages. The majority of the genetic diversity was explained by genetic differences among lineages, as shown the AMOVA analysis (F ST= 82%). The Network analysis shown two cluster clearly separated made up of those haplotypes belonging to each haplogroup. <![CDATA[<b>Population genetic parameters of the sheep populations from the Comunidad Autónoma de Cantabria</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300026&lng=en&nrm=iso&tlng=en Se caracterizaron genéticamente dos poblaciones ovinas, Guriezo y Blanca de la Peña, presentes en la C.A. de Cantabria y se analizaron las relaciones con otras razas afines geográfica o culturalmente. Para ello se genotiparon un total de 21 marcadores de tipo microsatélite en 457 muestras pertenecientes a las dos razas locales cántabras, y a las razas Lacha, Bardhoka, Anogeiano, Gentile di Puglia, Laticauda, Churra Bragancana, Colmenareña, Manchega, Merina, Rubia del Molar y Segureña. Los resultados indicaron la proximidad genética esperada entre la oveja Lacha y la población de Guriezo, y la diferenciación de las dos poblaciones cántabras (tanto Guriezo como Blanca de la Peña) con respecto a las demás razas ovinas estudiadas.<hr/>Two sheep populations present in the Cantabria region in the North of Spain and named Guriezo and Blanca de la Peña were genetically characterised, also their origin and relationships with other geographically or culturally connected breeds were studied. A total of 457 individuals belonging to the two groups and to other such as Lacha, Bardhoka, Anogeiano, Gentile di Puglia, Laticauda, Churra Bragancana, Colmenareña, Manchega, Merina, Rubia del Molar and Segureña breeds were genotyped for 21 microsatellite markers. The results allow detecting the influence of the Lacha breed on the Guriezo population, but also the genetic differences of both sheep populations (Guriezo and Blanca de la Peña) from all others ovine breeds studied. <![CDATA[<b>Genetic characterization of the Caballo Monchino breed and its relationships with other Spanish local equine breeds</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300027&lng=en&nrm=iso&tlng=en Para la caracterización genética de una población de Caballo Monchino se ha utilizado la información proporcionada por 12 marcadores del tipo microsatélite. Además se utilizaron 481 muestras de otras 7 razas autóctonas y se calcularon los parámetros de diversidad genética poblacional, los estadísticos F de Wright (F IS, F ST) y un análisis de correspondencia. Se puede concluir que se trata de una población significativamente diferenciada.<hr/>In this study 12 microsatellite markers are used to characterize the Caballo Monchino horse breed and to known the genetic relationships with other Spanish local horse breeds. The genetic diversity, allelic frequencies, heterozygosity, Wright's F statistics (F IS and F ST) was calculated, and to establish the genetics relationship between Mediterranean horse populations a correspondence analysis was carried out. <![CDATA[<b>Growth and carcass parameters of the Ovella Galega sheep breed lambs at the slaughter age of 45 days</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300028&lng=en&nrm=iso&tlng=en Actualmente la raza Ovella Galega se encuentra en peligro de extinción, por lo que está sometida a un Programa de Conservación y Recuperación donde prima la preservación de la variabilidad genética. En este trabajo se estudió el crecimiento y la canal en corderos de la raza, para profundizar en su caracterización. Se han utilizado 10 corderos machos de parto simple inscritos en el Libro Genealógico de la raza, criados sólo con leche materna hasta la edad de sacrificio de 45 días. El crecimiento y las GMD son acordes con los resultados publicados en otros estudios sobre la raza, y a pesar de que ésta presenta un pequeño formato, entre los resultados obtenidos cabe destacar su alto rendimiento comercial (59%) así como un adecuado porcentaje en piezas de 1ª y 2ª categoría.<hr/>The Ovella Galega is a endangered sheep breed and is protected by a Conservation and Recovery Programme, in order to keep the genetic variability. A growth and carcass study was made on Ovella Galega lambs, whose main objetive is its characterization. Ten male lambs from single birth and fed solely on their mother´s milk, all of them registered in the Record of Births of Stud-Book, were slaughtered at 45 days old. The growth and average dayly gain are in accordance to results published in other breed studies. The results show a high commercial yield (59%), apart from appropriate percentages in 1st and 2nd market categories. <![CDATA[<b>Growth and carcass parameters of the Ovella Galega sheep breed lambs at the slaughter age of 45 days</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300028&lng=en&nrm=iso&tlng=en Actualmente la raza Ovella Galega se encuentra en peligro de extinción, por lo que está sometida a un Programa de Conservación y Recuperación donde prima la preservación de la variabilidad genética. En este trabajo se estudió el crecimiento y la canal en corderos de la raza, para profundizar en su caracterización. Se han utilizado 10 corderos machos de parto simple inscritos en el Libro Genealógico de la raza, criados sólo con leche materna hasta la edad de sacrificio de 45 días. El crecimiento y las GMD son acordes con los resultados publicados en otros estudios sobre la raza, y a pesar de que ésta presenta un pequeño formato, entre los resultados obtenidos cabe destacar su alto rendimiento comercial (59%) así como un adecuado porcentaje en piezas de 1ª y 2ª categoría.<hr/>The Ovella Galega is a endangered sheep breed and is protected by a Conservation and Recovery Programme, in order to keep the genetic variability. A growth and carcass study was made on Ovella Galega lambs, whose main objetive is its characterization. Ten male lambs from single birth and fed solely on their mother´s milk, all of them registered in the Record of Births of Stud-Book, were slaughtered at 45 days old. The growth and average dayly gain are in accordance to results published in other breed studies. The results show a high commercial yield (59%), apart from appropriate percentages in 1st and 2nd market categories. <![CDATA[<b>Physico-chemical properties, fatty acids and amino acids found in 45 days old Ovella Galega lambs</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300029&lng=en&nrm=iso&tlng=en Se han analizado los parámetros fisicoquímicos, y el perfil de aminoácidos y de ácidos grasos en corderos de Ovella Galega alimentados exclusivamente con leche materna y sacrificados a los 45 días. Debe destacarse el bajo porcentaje de grasa intramuscular (0,62%) y dureza media-baja (4 kg/cm²). El perfil aminoacídico se aproxima al de una proteína de alta calidad. Entre los ácidos grasos se aprecia alto porcentaje de insaturados (55%) tanto mono como poliinsaturados, y menor de saturados (44,82%). La relación ω6/ω3(1,88) es adecuada.<hr/>There were analyzed the physico-chemical properties and the profile of amino acids and fatty acids found in lambs of the Ovella Galega breed fed solely on their mother's milk and slaughtered at 45 days. The results show a low percentage of intramuscular fat (0.62%) and lower-middle hardness (4 kg/cm²). The amino acids' profile is similar to that of a high quality protein. Concerning the fatty acids' profile, the study shows a high percentage of unsaturated (55%), both mono and polyunsaturated, versus a lower percentage of the saturated ones (44.82%), apart from a well proportioned ratio ω6/ω3(1,88). <![CDATA[<b>Goat biodiversity in Spain</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300030&lng=en&nrm=iso&tlng=en La especie caprina se localiza predominantemente en la España seca con gran protagonismo de Andalucía, Castilla-La Mancha, Canarias, Murcia y Extremadura. En este trabajo se analizan 867 muestras de 18 poblaciones caprinas españolas provenientes de diferentes zonas de la Península Ibérica (Azpi-Gorri, Blanca de Rasquera, Blanca Andaluza, Blanca Celtibérica, Florida, Malagueña, Murciano-Granadina, Negra Serrana, Payoya y Retinta) y de los archipiélagos Balear (Ibicenca, Mallorquina y cabra de Formentera) y Canario (Ajuí, Majorera, Palmera, Tinerfeña del Norte y Tinerfeña del Sur). Se amplifican 23 microsatélites de ADN y se determina la variación genética de las razas mediante el análisis del número medio de alelos, la heterocigosis, y el estadístico F IS. Los valores de heterocigosis esperada (He) oscilan entre 0,524 en la raza Palmera y 0,721 en la Florida mientras que la heterocigosis observada (Ho) fluctúa entre 0,515 en la Palmera y 0,705 en la Retinta. En España existe una diversidad genética caprina elevada con valores de número medio de alelos, heterocigosis esperada y observada para todas las razas de 7,04, 0,668 y 0,621 respectivamente.<hr/>Goats are located predominantly in the dry Spain specially in Andalusia, Castilla-La Mancha, the Canary Islands, Murcia and Extremadura. In this paper we have analyzed 867 samples of 18 Spanish goat populations from different parts of the Iberian Peninsula (Azpi-Gorri, Blanca de Rasquera, Blanca Andaluza, Blanca Celtibérica, Florida, Malagueña, Murciano-Granadina, Negra Serrana, Payoya and Retinta) and the Balearic (Ibicenca, Mallorquina and Formentera goat) and Canarian Archipelagos (Ajuí, Majorera, Palmera, Tenerife North and Tenerife South). Twenty-three microsatellites have been amplified and the withinbreed genetic variation has been calculated through the analysis of the mean number of alleles, heterozygosity and F IS The values of expected heterozygosity (He) per breed ranged from 0.524 to 0.721 in Palmera and Florida, respectively, while the observed heterozygosity (Ho) ranged between 0.515 and 0.705 in Palmera and Retinta, respectively. Goat genetic diversity in Spain is very high, with a mean number of alleles, expected and observed heterozigosities across the breeds of 7.04, 0.668 and 0.621, respectively. <![CDATA[<b>Development of DNA fragmentation in semen criopreservation of Fighting bull</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300031&lng=en&nrm=iso&tlng=en El objetivo de este trabajo fue analizar la curva de fragmentación del ADN espermático en semen criopreservado de 10 sementales de la raza de Lidia y observar su evolución a diferentes intervalos de tiempo preestablecidos. Se descongelaron las dosis a 37ºC y se incubaron durante 10 días a 38,6ºC, simulando la temperatura corporal de la hembra. Se analizó el porcentaje de fragmentación del ADN espermático de cada muestra a las 4, 24, 48 y 72 horas y a los 4, 5, 6, 7, 8, 9 y 10 días de incubación utilizando el kit Sperm-Halomax®-Bos-FF (ChromaCell SL, Madrid, Spain) para microscopía de fluorescencia. Los resultados obtenidos indican que: (i) Los niveles de fragmentación basal, así como la velocidad de degradación del ADN espermático a diferentes tiempos de incubación, presentan importantes diferencias interindividuales. (ii) A falta del estudio de un mayor número de muestras, se podría considerar que en esta raza, la integridad de la molécula de cromatina se rompe cuando el semen es incubado a una temperatura de 38,6ºC, pero aún así, puede permanecer estable durante un prolongado período de tiempo. Aquellos sementales con altos porcentajes de fragmentación y que acumulan daños en su ADN espermático rápidamente, tendrían escasas posibilidades de conseguir la fertilización. Por tanto, sería interesante conocer la curva de fragmentación del ADN de cada muestra seminal criopreservada, porque proporcionaría información muy valiosa para establecer la mejor estrategia de reproducción asistida y esclarecer problemas de infertilidad o de falta de desarrollo embrionario cuando se aplican estas técnicas.<hr/>The objective of the present study was to analyze the curve of sperm DNA fragmentation and its development during a pre-established period of time, in cryopreserved semen of 10 bulls from Lidia's breed. Semen samples were thawed at 37ºC and were preserved in incubation up to 10 days at 38.6ºC, to emulate the corporal temperature in the female. Analysis of DNA fragmentation was assessed after 4, 24, 48, 72 hours and at 4, 5, 6, 7, 8, 9 and 10 days of incubation from each sample. Sperm-Halomax®-Bos-FF kit (ChromaCell SL, Madrid, Spain) was used to determine this parameter, by fluorescence microscopy. The results obtained indicated that: (i) Basal levels of fragmentation, and the velocity of sperm DNA degradation between different times, presented variation among individuals. (ii) We can consider that in these breed, the nuclear chromatin integrity gets degraded when it is incubated at a temperature of 38.6ºC and can remain stable for long periods of time. Those bulls that present high percents of fragmentation index and a high speed of damage accumulation have a low potential to achieve fertilization. Therefore, it would be interesting to determinate the curve of DNA fragmentation in each cryopreserved sample, because it would supply information when establishing the best strategy for use to assisted reproduction techniques and it could clarify infertility or embryonic development problems for artificial insemination protocols. <![CDATA[<b>Comparison of zoometric measurements in Balearic hens</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300032&lng=en&nrm=iso&tlng=en Se han tomado un total de 26 medidas craneales y corporales y 8 índices en 42 gallinas baleares de cada una de las razas Ibicenca, Menorquina y Mallorquina bajo condiciones de manejo estándar. La gallina Ibicenca ha sido la más pesada, con el cráneo y la quilla más largos y con mayor diámetro del tarso. La Menorquina ha mostrado los ojos más alargados, la cresta y las orejillas más grandes y las barbillas más largas y también han sido mayores el cuello, dorso, cola, ala plegada, muslo, medida ornitológica y envergadura. La gallina Mallorquina ha presentado menor peso e inferiores valores de las mediciones. En cuanto a los índices, la gallina Ibicenca ha obtenido un mayor índice craneal e índice de orejillas; la Menorquina mayor índice de barbillas y la Mallorquina superior índice de cresta. La Mallorquina presentó el índice de pechuga más bajo.<hr/>A total of 26 head and body measurements and 8 indexes have been taken in 42 hens of each Balearian breed: Ibizan, Minorca and Majorcan. These hens have been bred in standard conditions. The results have shown that Ibizan has been the heaviest one, and the one which has scored the longest cranium and keel of sternum too. Furthermore it has also reported a higher tarsus diameter. Minorca has achieved the highest eye and wattle length and the biggest comb and ear lobes, the longest neck, back, tail, folding wing and thigh and the biggest ornithological measure and wingspan. Majorcan is the lightest one and it has scored minor values. Ibizan hen has obtained a higher cranium and ear lobe index. Minorca has scored the higher value for the wattle index and Majorcan has achieved a bigger comb index. Majorcan hen showed the lower chest index. <![CDATA[<b>Preliminary results of the study of the carcass quality of the Majorcan cattle breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300033&lng=en&nrm=iso&tlng=en La raza bovina Mallorquina, tras haber estado muy cerca de la extinción, se encuentra en plena recuperación a causa de la puesta en valor de sus productos cárnicos, los cuales se comercializan de forma muy restringida con un alto valor agregado. Se hizo necesario caracterizar dichos productos para protegerlos de fraudes o imitaciones que pudieran poner en riesgo su credibilidad en el consumidor. En el presente estudio se aportan los resultados preliminares de la caracterización de la canal del producto más considerado de la raza, la carne de bou. Se estudiaron las características de las canales de 7 toros de la raza como parte del trabajo de caracterización productiva. Los animales sacrificados fueron machos sin castrar con una edad media en torno a los 32 meses de edad al sacrificio estudiándose los pesos, rendimientos y morfometría, así como el pH y la clasificación comercial de la canal. Al despiece se calcularon los porcentajes de composición de la canal en hueso, grasa y carne, y se realizó un seguimiento del despiece comercial. Las canales producidas son pesadas de buen rendimiento de la canal, bajo contenido en grasa y alto en músculo y hueso. Se trata de un producto totalmente diferenciable y protegible bajo una marca de calidad.<hr/>Mallorquina cattle breed, after a period of extreme endangering, is in a recuperation process because of the valuation of their meat products; they are commercialized in a restricted way with a high added value. The characterization of these products became necessary to protect them from frauds and imitations which could put in risk its credibility in the consumer. In the present study preliminary results on the characterization of the most valuated product of the breed, the bou meat, are presented. Carcass characteristics of 7 bulls of the breed were studied as a part of the productive characterization of the breed. Animals were no castrated males slaughtered with a mean age around 32 months. Weights, yields and morphometry were studied in the carcasses, together with pH and commercial classifications. After commercial cutting, the bone, fat and muscle composition of the carcasses were determined. Carcasses obtained were heavy with good carcass yields, low fat contents and high in bone and muscle. It is a product easily to differentiate and protect under a quality trade mark. <![CDATA[<b>Physic-chemical study of the Marismeña cattle breed meat in different fattening systems</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300034&lng=en&nrm=iso&tlng=en El bovino Marismeño es una entidad racial asilvestrada incluida en un sistema agroecológico prezootécnico, el Espacio Natural de Doñana que no encuentra una vía de comercialización adecuada que la diferencie de lo típicamente comercial, y, por tanto, agregue valor para competir mediante una calidad diferenciada. En este trabajo se presentan los resultados preliminares del estudio físico-químico de la carne. Se han estudiado 17 animales de la raza en dos sistemas de terminación diferentes, su entorno natural (extensivo) y un cebadero comercial (intensivo). La carne mostró diferencias significativas entre los sistemas de producción para los resultados de los análisis químicos y el color a las 24 horas postmortem. Los animales del sistema extensivo mostraron carnes magras, con un alto porcentaje de humedad, y una coloración con menores intensidades de rojo (p<0,01) y amarillo (p<0,001), comparada con los animales del intensivo. Los resultados demuestran una diferenciación entre ambos sistemas, a la vez que se hallan algunas características que conducen a la diferenciación del producto de esta raza bovina en el mercado.<hr/>Marismeña cattle breed is a feral population included in a pre-zootechnic agro-ecosystem, the Doñana protected area. In spite of these characteristics so exclusives, the absence of characterization of their products difficults the finding of a way of commercialization differentiated of the typical commerce, adding value to product by way of a differentiated quality. The preliminary results of a meat physic-chemical study are presented. Seventeen animals of the breed have been studied reared in two different systems of fattening: its natural context and a commercial fattening station. Meat shown significant differences between the management systems for the results of the chemical analysis and colour at 24 hours posmortem. Animals belonging to the extensive system shown meat low in fat, with a high percentage of humidity, and colour with lower tone of red (p<0.01) and yellow (p<0.001), when compared with intensive animals. Results demonstrated a differentiation between both systems, together with some arguments to differentiate the products of this breed in the market. <![CDATA[<b>Parameters and genetic trends of cattle weight rising in pasture in Brazil</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300035&lng=en&nrm=iso&tlng=en Parâmetros e tendências genéticas para os pesos aos 120 (P120: n= 86 852), 205 (P205: n= 86 852), 365 (P365: n= 61 637) e 550 (P550: n= 36 187) dias de idade foram estimados para animais da raça Nelore criados a campo nas regiões Centro-Oeste e Sudeste no Brasil. Os dados são provenientes da ABCZ/EMBRAPA e foram obtidos no período entre 1975 a 2001. Os parâmetros foram obtidos utilizando o programa MTDFREML, em análise unicaracterística. Os efeitos fixos foram grupo de contemporâneos (combinação de estação (água e seca), ano, sexo e fazenda) e a covariável idade da vaca ao parto (linear e quadratico). Como efeito aleatório utilizouse o efeito aditivo direto, aditivo materno, e de ambiente permanente. As estimativas das variâncias genéticas, direta e materna, ambientais e fenotípicas e as covariâncias entre o efeito direto e materno foram 51,1; 17,9; 190,5; 280,4 e -12,0 para P120; 128,6; 47,2; 695,7; 932,4 e -25,9 para P205; 435,9; 32,2; 2934,0; 3604,9 e -27,4 para P365; 607,9; 177,7; 5637,7; 6602,5 e -117,6 para P550. Os valores de herdabilidades direta encontram-se na faixa de 0,09 a 0,18; herdabilidade materna variaram de 0,01 a 0,06, correlação direta materna entre -0,23 a -0,36 e o efeito de ambiente permanente igual a 0,05 a 0,12. As estimativas das tendências genéticas, direta materna, e ambientais no período de 1975 a 2001 foram 10,4; -1,6 e 18,4 kg para P120; 16,6; -2,8 e 23,0 kg P205; 21,7; -1,3 e 23,6 kg para P365; 25,5; -3,6 e -8,1 kg para P550, respectivamente. As tendências genéticas diretas foram positivas e as maternas pequenas e negativas. O desempenho materno tem influencia importante sobre os pesos aos 120 e 205 dias de idade e esse baixo valor obtido sugere que se deve considerar para este efeito nos programas de melhoramento, mesmo se tendo correlação direta materna adversa.<hr/>Genetic parameters and trends of weights were estimated for Nellore cattle from Central west and South East in Brazil. ABCZ/EMBRAPA provided weights (kg) at 120 (W120), 205 (W205), 365 (W365) and 540 (W540) for 86 852, 86 852, 61 637, 36 187 animals, respectively, from 1975 to 2001. Parameters were obtained using MTDFREML in single trait analyses. Fixed effects were contemporary group (dry or wet season), year, sex and farm and age of dam (linear and quadratic covariate). Random effects were direct and maternal genetic effects, their covariance, and the uncorrelated maternal permanent environmental effect. The analysis was restarted until twice the logarithms of the likelihoods changed no more than two decimal places. Estimates of direct and maternal genetic variances, direct-maternal covariance, and environmental and phenotypic variances were [51.1, 17.9, -12.0, 190.5 and 280.4] for W120; [128.6, 47.2, -25.9, 695.7 and 932.4] for W205; [435.9, 32.2, -27.4, 2934.0 and 3604.9] for W365; and [607.9, 177.7, -117.6, 5637.7 and 6602.5] for W540. Direct heritabilities ranged from 0.09 to 0.18, maternal heritabilities from 0.01 to 0.06, direct-maternal genetic correlations from -0.23 to -0.36, and permanent environmental effects from 0.05 to 0.12. Direct and maternal genetic and environmental trends from 1975 to 2001 were 10.4, -1.6 and 18.43 kg for W120; 16.6, -2.8; and 23.0 kg for W205; 21.7, -1.3 and 23.6 kg for W365, and, 25.5, -3.6, and -8.1 kg for W540, respectively. The direct genetic trends were positive and maternal trends were small. The importance of maternal performance for W120 and W205 suggests it should be considered in breeding programs although it has a low heritability and modestly adverse genetic correlation with direct genetic effects. <![CDATA[<b>Comparison among methodologies for evaluation of age at first conception in Thoroughbred mares</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300036&lng=en&nrm=iso&tlng=en No Brasil, devido à existência do ano hípico para a raça Puro-Sangue Inglês, os dados reprodutivos são geralmente truncados, já que os criadores tentam obter produtos nascidos no começo do ano hípico, a fim de aproveitarem a vantagem competitiva (animais mais desenvolvidos, maduros e treinados) destes em relação aos animais nascidos mais tardiamente no mesmo ano hípico. Para análise destes dados deve-se utilizar metodologias adequadas. Sendo assim, este trabalho objetivou comparar três metodologias: método da máxima verossimilhança restrita, com a utilização do aplicativo MTDFREML, análise bayesiana sem dados censurados por meio do programa MTGSAM e análise bayesiana com dados censurados pelo programa LMCD, para avaliação da idade à primeira concepção em éguas da raça Puro-Sangue Inglês, a fim de verificar seu impacto na escolha de reprodutores durante a seleção. O arquivo de dados continha 3509 registros de idade à primeira concepção (meses) de éguas da raça Puro-Sangue Inglês. As estimativas de herdabilidades obtidas foram 0,23, 0,30 e 0,0926 (escala log), para o MTDF, MTGSAM e LMCD, respectivamente. Considerando todos os animais do pedigree (6713), as correlações de ranking variaram de 0,91 a 0,99. Quando considerado apenas os garanhões (656), variaram de 0,48 a 0,99 (considerando diferentes porcentagens de machos selecionados) entre as metodologias de avaliação. As maiores mudanças na classificação geral foram observadas quando comparado o LMCD com as outras duas metodologias. Considerando que o modelo linear censurado é o mais adequado para análise de características com dados censurados, observouse que as informações de censura levariam a escolha de diferentes animais durante o processo de seleção, quando comparado com as outras duas metodologias de análise.<hr/>In Brazil, due to the breeding season for Thoroughbred, the reproductive data are normally truncate, since the breeders try to get animals that were born at the beginning of the breeding season in order to take their competitive advantages (more developed, mature and trained animals) compared to animals born later in the same breeding season. To analyze these data suitable methods should be used. Then, this paper aims to compare three methodologies: the method of maximum restricted likelihood, using MTDFREML, bayesian analysis without censured data by software MTGSAM and bayesian analysis with censured data by software LMCD, to evaluate age at first conception in thoroughbred mares, in order to verify its impact on the choice of stallions during selection. The database contained 3509 records for age at first conception (months) for thoroughbred mares. The heritability estimates were 0.23, 0.30 and 0.0926 (log scale), for MTDF, MTGSAM and LMCD, respectively. Considering all animals in the pedigree (6713), ranking correlations varied from 0.91 to 0.99. When only stallions were considered (656), those varied from 0.48 to 0.99 (considering different percentages of selected males) between evaluation methods. The highest changes in the general classification were observed when LMCD was compared to the other two methods. As the linear censured model is the most suitable for trait analysis with censured data, it was observed that censure information would lead to the choice of different animals during the selection process, when compared to the two other methodologies. <![CDATA[<b>Production, digestibility and cost/benefit of lamb's diets including <i>Acacia farnesiana</i> pods</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300037&lng=en&nrm=iso&tlng=en Con el objetivo de evaluar el uso de vainas de Acacia farnesiana en la alimentación de ganado lanar se hizo un experimento con corderos de raza Chiapas en crecimiento, que recibieron dietas (T) isoproteínicas con diferentes niveles de inclusión de vainas: T1= 0, T2= 100, T3= 200, T4= 300 y T5= 400 g/kg (base seca) elaboradas con rastrojo de maíz, harina de soja, salvado de trigo y mezcla de minerales; se estudió la respuesta productiva, digestibilidad y análisis de beneficio-costo. Se utilizaron corderos en confinamiento y alimentación controlada bajo un diseño completamente el azar con cinco tratamientos y cinco repeticiones. El contenido de proteína bruta (PB) de las vainas fue de 115,2 g/kg (MS) y de taninos 7,8 g/kg. El consumo voluntario fue mayor (p<0,05) en T4 en relación al grupo control; en tanto la conversión alimenticia y la ganancia diaria de peso fueron similares (p&gt;0,05) entre tratamientos. La producción de lana no mostró diferencias (p&gt;0,05) en peso del vellón sucio y rendimiento al lavado; no obstante, el crecimiento de lana por unidad de superficie (mg/cm²/día) fue mayor (p<0,05) con la inclusión de 200 g/kg en la dieta. No hubo diferencias de digestibilidad de la materia seca y fibras (p<0,05), mientras que el beneficio-costo con mayor índice fue T4. Se concluye que la inclusión hasta 400 g/kg de vainas de Acacia farnesiana en dietas para corderos en crecimiento no disminuye la respuesta productiva o la digestibilidad, mientras que con 200 g/kg se mejoró el consumo voluntario y el crecimiento de lana, por lo que se puede recomendar su uso para bajar los costos de alimentación.<hr/>Aiming to evaluate the use ofAcacia farnesiana pods in sheep feeding, an experiment was carried out with growing lambs receiving isoproteinic diets (T) with different inclusion levels of pods: T1= 0, T2= 100, T3= 200, T4= 300 and T5= 400 g/kg (dry basis) prepared with maize fodder, soybean meal, wheat bran and minerals mix; productive performance, digestibility and cost-benefit analysis were assessed. Fifty lambs of the Chiapas breed were utilized, kept in closed confinement under a controlled feeding regime, using a completely at random design with five treatments and five repetitions. The crude protein content (CP) of pods was 115.2 g/kg (DM) and tannins were 7.8 g/kg. Voluntary intake was higher (p<0.05) in T4 as compared with the control group; feed conversion and average daily gain were similar (p&gt;0.05) among treatments. Wool production showed no per unit area (mg/cm²/day) was higher (p<0.05) with the inclusion of 200 g/kg of pods in the diet. Dry matter and fiber digestibility showed no differences (p<0.05) among treatments, while the cost-benefit ratio was better for T4. It is concluded that the inclusion up to 400 g/kg ofAcacia farnesiana pods in the diet of growing lambs did not have an effect on their productive response or the digestibility, whereas 200 g/kg improved voluntary intake and wool growth, and thus its use may be recommended to lower food costs. <![CDATA[<b>Cassava root meal in diets of free-range broiler chickens</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300038&lng=en&nrm=iso&tlng=en O objetivo do trabalho foi avaliar níveis de inclusão de farelo da raiz integral de mandioca, em dietas de frangos de corte tipo caipira, sobre o desempenho, os rendimentos de carcaça, de cortes e as propriedades funcionais da carne. Foram distribuídos 384 pintainhos machos da linhagem ISA S757-N (pescoço pelado) em um delineamento inteiramente casualizado com quatro tratamentos e quatro repetições de 24 aves cada. Os tratamentos foram 0%, 20%, 40% e 60% de FRIM (farelo da raiz integral de mandioca) na ração total. O período experimental foi dividido em três fases de criação: inicial (1 a 28 dias de idade), crescimento (29 a 56 dias de idade) e engorda (57 a 84 dias de idade). Foram obtidos o peso corporal final (PF), o ganho de peso (GP), consumo de ração, conversão alimentar e viabilidade. Aos 84 dias foram obtidos os rendimentos de carcaça, peito, coxa+sobrecoxa, asa, dorso gordura abdominal e das carnes de peito das aves foram determinados o pH, capacidade de retenção de água (CRA) e perda de peso por cozimento (PPC). Por comparação visual, foram determinados os escores para as cores de pele de canela e de peito. Os resultados foram submetidos à análise de variância, à análise de regressão e as médias foram comparadas pelo teste de Tukey a 5% de probabilidade. A análise de variância detectou diferença significativa entre os tratamentos para PF e GP, somente na fase de 1 a 28 dias de idade. Foi verificado aumento linear para PF e GP à medida que se aumentou o nível de inclusão de FRIM na ração. Não existiram diferenças significativas entre os tratamentos para as variáveis de rendimento de carcaça, de cortes, pH, CRA e PPC. A utilização do FRIM nas dietas de frangos de corte tipo caipira promoveu redução linear na coloração das peles da canela e do peito das aves com o aumento do nível de inclusão desse ingrediente nas rações. O farelo da raiz integral de mandioca pode ser utilizado nas dietas de frangos de corte tipo caipira na proporção de 60% da ração total sem prejudicar o desempenho, os rendimentos de carcaça, de corte e as propriedades funcionais da carne, no entanto promove descoloração das peles de canela e peito.<hr/>The aim this work was to evaluate cassava root meal inclusion levels in diets of free-range broiler chickens on performance, carcass yield, parts yield and functional properties of the meat. 384 male chickens of ISA S757-N strain (naked neck) were distributed in a completely randomized design with four treatment and four replicates of 24 birds each. The treatments were 0%, 20%, 40% and 60% of FRIM (cassava root meal) in the total ration. The trial period was divided into three rearing phases: initial (1 to 28 days of age), growth (29 to 56 days of age) and fattening (57 to 84 days of age). Final body weight (PF), weight gain (WG), feed intake, feed conversion and liveability were evaluated. At 84th day, carcass, breast, thigh + upper thigh, wing, back and abdominal fat yield were obtained. Breast meat was used to determine the pH, water holding capacity (CRA) and cooking loss (PPC) too. The shank and breast skin color scores were determined by visual comparison. The results were submitted to analysis of variance, analysis of regression and averages were compared by Tukey's test to 5% of probability. The analysis of variance found a significant difference between treatments for BW and WG, only at the phase of 1 to 28 days of age. There was a linear increased in BW and WG when the CRM inclusion level increased in feed. There were no significant differences between the treatments for the variables of carcass yield, cuts yield, pH, CRA and PPC. The use of FRIM in the diets of freerange broiler chickens promoted linear reduction in the shank and breast skin colors with the increase of the inclusion level of this ingredient in the feed. The FRIM can be used in the diets of freerange broiler chickens in the proportion of 60% of total ration without resulting in worst performance, carcass yield, cuts yield and functional properties of the meat, however it promotes shank and breast skin no coloration. <![CDATA[<b>Effects of reducing postpartum re-mating timeperiod on reproductive performance of the doe</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300039&lng=en&nrm=iso&tlng=en Rabbits being induced ovulators can be rebred within 24 hours after parturition. However, reproductive efficiency and the doe's physiology can be affected by postpartum re-mating interval. This study evaluated the effects of reducing the re-mating interval after parturition on sexual activity, fertility, gestation, parturition and litter characteristics using 90 does. Three groups of crossbred (New Zealand White × Chinchilla) does were used in a randomized complete block design. Does were re-mated 1-9, 10-20 and 21-28 days after parturition in the dry and rainy seasons in Ayetoro, Ogun State, Nigeria. Acceptance of mating decreased with increasing postpartum remating interval. Conception rate was highest in the 21-28 days group (98.8%) and lowest in the 1020 days group (68.4%). Gestation length was significantly shorter (p<0.05) in the 10-20 days group (30.7 days), than 1-9 days group (31.6 days) and 21-28 days group (31.7 days). Litter size and weight at birth were not significantly affected. Kit's mortality was lower (p<0.05) in the 21-28 days group (25.6%) compared to 10-20 days group (57.4%) and 1-9 days group (58.8%). Litter weight (total and alive at birth) was heavier (p<0.05) during the rains (295.9 and 294.9 g) than dry season (250.1 and 243.3 g). Reducing the re-mating interval after parturition enhanced sexual activity. Fertility was comparable in does re-mated 1-9 and 21-28 days after parturition.<hr/>Les lapins étant des ovulateurs incités peuvent reprocréer en moins de 24 heures après la parturition. Cependant l'intervalle de récopulation postpartum peut influer sur el efficacité de reproduction et sur la physiologie de la lapine. Cette étude a évalué les effets de la réduction de l'intervalle de ré-accouplement après la naissance sur l'activité sexuelle, la fertilité, la gestation, la parturition et les caractéristiques des petits, en utilisant 90 lapines. Trois groupes de lapines de race croisée (New Zealand White × Chinchilla) ont été utilisés dans un bâtiment découpé en cabines de dimensions prises au hazard. Les lapines ont été ré-accouplées entre 1 à 9, 10 à 20, 21 à 28 jours après la parturition les saisons sèches et pluvieuse à Ayetoro, dans e' Etat d'Ogun au Nigeria. L'acceptation de récopulation a décru avec l'accroissement de l'intervalle de récopulation postpartum. Le taux de conception était le plus élevé dans le groupe de 21 à 28 jours (98,8%) et le plus bas dans le groupe de 10 à 20 jours (68,4%). La durée de gestation était considérablement plus courte (p<0,05) dans le groupe de 10 à 20 jours (30,7 jours) que dans le groupe de 1 à 9 jours (31,6 jours) et que dans le groupe de 21 à 28 jours (31,7 jours). La grosseur et le poids des petits à la naissance n'étaient pas pour autant affectés. La mortalité à la naissance était plus basse (p<0,05) dans le groupe de 21 à 28 jours (25,6%) par rapport aux groupes de 10 à 20 jours (57,4%) et de 1 à 9 jours (58,8%). Le poids des petits (total et vivants à la naissance) était plus lourd (p<0,05) pendant les pluies (295,9 et 294,9 g) que pendant la sécheresse (250,1 et 243,3 g). La réduction de l'intervalle de récopulation après parturition a augmenté l'activité sexuelle. La fertilité était comparable chez les lapines ré accouplées dans les groupes de 1 à 9 et de 21 à 28 jours après parturition. <![CDATA[<b>Genetic parameters in milk production and longevity traits of Mambí de Cuba cows</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300040&lng=en&nrm=iso&tlng=en Se utilizaron los datos de 6335 vacas de la raza Mambí de Cuba (3/4 Holstein 1/4 Cebú) provenientes de 4 empresas genéticas, con partos desde 1980 a 2005, para estimar las heredabilidades (h²) y las correlaciones genéticas y fenotípicas para la producción de leche en la primera lactancia (LPL), la producción de leche total acumulada por vida (LTV), vida productiva (VP) y habilidad de permanencia hasta 36 meses de vida productiva (HP36). Para estimar los componentes de varianza se utilizó el programa MTDFREML empleando un modelo animal uni o bivariado que incluyó como efecto fijo la combinación rebaño-año-época de primer parto, la edad al primer parto como covariable lineal y cuadrática y como efectos aleatorios el animal y el error. Los promedios para LPL, LTV, VP y HP36 fueron de 1990,9 kg, 9749,5 kg, 69,7 meses, 0,77% y las heredabilidades fueron de 0,15±0,03, 0,10±0,03, 0,05±0,02, 0,008±0,013. Las correlaciones genéticas de la leche acumulada por vida con los rasgos de longevidad fueron altas (0,59 y 0,80) y aquellas entre la producción lechera en la primera lactancia y los rasgos de longevidad fueron bajas y antagónicas (-0,13 y -0,16). En el programa de mejoramiento genético de la raza, al seleccionar los futuros sementales, además de la producción lechera se deben incluir rasgos que garanticen la permanencia de los animales en el rebaño.<hr/>Data from 6335 cows of the Mambí de Cuba (3/4 Holstein 1/4 Zebu) breed from four genetic enterprises, with calving in the years from 1980 to 2005 were used to estimate the heritabilities and the genetic and phenotypic correlations of milk production in the first lactation (LPL), the total milk production accumulated for life (LTV), productive life (VP) and stayability for 36 month of productive life (HP36). The MTDFREML program was used to estimate the variance component using uni or bivariate animal model that included the fixed effect of herd-years-season of first calving, the age to first calving as lineal and quadratic covariable, and as random effect the animal and the residual. The means for LPL, LTV, VP and P36 were of 1990.9 kg, 9749.5 kg, 69.7 month, 0.77% and the heritabilities were of 0.15±0.03, 0.10±0.03, 0.05±0.02, 0.008±0.013. The genetic correlations of milk production acumulated for life with the longevity traits were high (0.59 and 0.80) and those between milk production in the first lactation and the longevity traits were low and antagonic (-0.13 and -0.16). In the genetic improvement of breed for selecting the future sire, besides milk production, traits that guarantee the stayability of the animals in the herd should be included. <![CDATA[<b>Polymorphisms in two candidate genes for beef quality in Argentina</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300041&lng=en&nrm=iso&tlng=en La calidad de la carne bovina está definida por muchos atributos. Está determinada por factores genéticos y ambientales (edad al sacrificio, alimentación, manejo anterior y posterior a la faena). La tendencia actual es estudiar genes candidatos con el propósito de desarrollar marcadores moleculares que puedan asistir a la selección. El objetivo de este trabajo fue evaluar el efecto de polimorfismos (SNP, single nucleotide polymorphisms) en genes candidatos para terneza y contenido de grasa en novillos engordados en condiciones de pastoreo de Argentina. Se diseñaron métodos moleculares para analizar el SNP 4751 (C/T) en el gen bovinocapn1 (subunidad mayor de la μ-calpaína), asociado con terneza y dos polimorfismos (exón 8:G/A, e intrón 9:C/T) en el gen bovino ppargc1a (coactivador 1 alfa del receptor gamma activado por proliferadores peroxisómicos) con efecto sobre contenido de grasa en leche bovina y tipo de fibra en cerdos. Para los análisis de asociación se utilizaron 60 novillos Brangus y 21 Angus con registros de terneza y grasa intramuscular. La terneza (Resistencia al Corte- por Cizalla de Warner-Bratzler) fue determinada en tres tratamientos de maduración (1, 7 y 14 días). Una gran proporción de animales heterocigotos (CT) se observó en el SNP 4751. No se encontró ninguna diferencia entre los genotipos de ese SNP para RC (Resistencia al Corte determinada por Cizalla de Warner-Bratzler). En el SNP del intrón 9 del gen ppargc1a se halló una baja frecuencia de homocigotos TT. No se encontraron diferencias en grasa intramuscular ni en terneza entre los genotipos para dicho SNP. Se identificaron dos nuevos polimorfismos (G/Ay C/T) en el exón 8 del gen ppargc1a, a partir de la comparación de secuencias obtenidas de 24 toros de razas distintas (Angus, Brangus, Brahman y Braford). Uno de ellos (G/A) podría provocar la sustitución de serina por asparragina en la posición 364 de la proteína. El alelo A no se encontró en Angus. El SNPC/T es una sustitución conservativa. Es importante que Argentina genere información sobre este tema para optimizar la producción y exportación de carnes de calidad.<hr/>Meat quality is a term used to describe a range of attributes of meat. It is determined by genetic and environmental factors (slaughter age, feeding and pre and post-slaughter management). The current tendency is to study the candidate genes in order to develop molecular markers, which might be used for marker-assisted selection. The objective of this work was to evaluate the effect of polymorphisms (SNP, single nucleotide polymorphisms) in candidate genes for tenderness and fat content in steers fattened in grazing beef production systems of Argentina. Molecular methods were designed to analyze the SNP 4751 (C/T) in bovine capn1 gene (large subunit of μcalpain), associated with tenderness and two polymorphisms (exon 8:G/A and intron 9:C/T) in bovine ppargc1a gene (peroxisome proliferatoractivated receptor gamma coactivator 1-alpha) with effect on fat content in cow milk and fiber type in pigs. Information of Warner-Bratzler shear force and fat content from 60 Brangus and 21 Angus steers was used in association studies. Tenderness of cooked meat was evaluated at 1.7 and 14 days post-mortem. A large proportion of animals were heterozygotes (CT) at SNP 4751. No differences were found between genotypes of this SNP for WBSF. A low frequency of homozygote TT was found at SNP on intron 9 of the ppargc1a gene. This SNP showed no significant effect on WBSF and fat content. Two new SNPs (G/A and T/C) were identified within exon 8 of the ppargc1a gene, by multiple alignment of DNA sequences obtained from 24 bulls of different breeds (Angus, Brangus, Brahman and Braford). One of them (G/ A) could be the cause of aminoacid substitution of serine by asparagine at position 364 of the protein. The A allele was not found in Angus. The SNP T/ C is a conservative substitution. It is important that Argentina generate information about factors affecting meat quality for optimizing the production and exportation of high quality beef. <![CDATA[<b>Physical and chemical characteristics of sorghum grain</b>: <b>Relationship with ruminal degradation in cattle</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300042&lng=en&nrm=iso&tlng=en Se estudió la relación entre las características físicas y químicas de diferentes híbridos de granos de sorgo y la degradabilidad in situ de la materia seca (MS), proteína bruta (PB) y almidón. Las características físicas (peso hectólitro, relación de molienda, porcentaje de flotación, densidad aparente) y químicas (taninos, PB y kafirinas) fueron relacionadas con la degradabilidad ruminal de los granos de sorgo para identificarlas como posibles predictoras de la misma. Se detectaron diferencias entre los híbridos en la degradabilidad in situ de la MS, PB y almidón tras 16 horas de incubación en el rumen. Las características físicas de los granos no se relacionaron con la degradabilidad in situ de los mismos. Sin embargo, los contenidos de taninos y de kafirinas de los granos estuvieron relacionados con la degradabilidad in situ de la MS, PB y almidón. La degradabilidad del grano de sorgo fue altamente dependiente del genotipo y el contenido de taninos fue el mejor predictor de la degradabilidad de la MS.<hr/>We studied the relationship between physical or chemical characteristics of different sorghum grain hybrids on in situ dry matter (DM), crude protein (CP) and starch degradability. Physical (bulk density, milling ratio, percentage of floating grains, apparent density) and chemical (tannins, CP and kafirins contents) characteristics were related to ruminal degradability of sorghum grains in order to identify predictors for ruminal degradation. Differences in DM, CP and starch degradability in situ between sorghum hybrids were found after 16 h of incubation. Physical characteristics were not related to in situ DM, CP and starch degradability. However, tannins and kafirins contents were related to DM, CP and starch degradability. Degradability of sorghum grain was highly dependent on genotype and tannin contents were the most reliable predictor of DM degradability. <![CDATA[<b>Population structure and genetic variability of the Marota goat breed</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300043&lng=en&nrm=iso&tlng=en A raça caprina Marota é parte do patrimônio genético do Brasil, formada por animais altamente adaptados ao semi-árido nordestino. Este estudo avaliou a estrutura genética do núcleo de conservação da raça Marota, mantida pela Embrapa Meio Norte. Foram estimados os parâmetros populacionais dos dados genealógicos de 663 animais nascidos entre os anos de 1995 a 2003. O coeficiente médio de parentesco (AR) e de consanguinidade (F) para a população foi de 0,11% e de 0,84%, respectivamente. O intervalo de gerações (IEG) foi de 5,28 anos e o tamanho efetivo médio (Ne) por geração foi de 222 animais, sendo que o número efetivo de animais fundadores (ƒe) e de ancestrais (ƒa) foi igual (48). Dentre os 214 ancestrais, apenas 22 foram responsáveis por 50% da variabilidade genética da população, o que indica perda de genes de origem. Observase baixa contribuição dos animais fundadores ao longo das gerações. Os valores do coeficiente de endogamia de Wright indicam subdivisão da população em linhagens. Em geral, a consangüinidade e os valores médios do coeficiente de parentesco são baixos para o rebanho avaliado.<hr/>Marota breed goat is part of the Brazilian genetic patrimony, consisting by animals highly adapted to semi-arid region. This study evaluated genetic structure of Marota breed from Embrapa Meio Norte conservation nucleus. Pedigree records of 663 animals, which were born from 1995 to 2003, were used for population parameters estimation. Inbreeding coefficient (F) and average relationship coefficient (AR) of the population were 0.11% and 0.84% respectively. Generation interval (IEG) was 5.28 years and average effective size (Ne) per generation was 222 animals; being the effective number of founder animals (ƒe) and ancestral (ƒa) was the same (48). Among 214 ancestors evaluated, just 22 of them were responsible for 50% of the population genetic variability, which indicate loss of original genes. This study shows low contribution of the founder animals among the generations. Wright inbreeding coefficient indicates population subdivision in lineages. Inbreeding and average relationship coefficient (AR) are low in the evaluated herd. <![CDATA[<b>Mineral composition of arboreal and bush species occurring in pastures, in Pernambuco-Brazil</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300044&lng=en&nrm=iso&tlng=en The aim of the present study was to evaluate, during the dry and wet seasons the mineral composition of tree and bush species occurring in pasture areas near the cities of Itambé, Caruaru and Serra Talhada in the humid, intermediate, and dry climatic zones of the state of Pernambuco (Brazil). Leaves and branches up to 5.0 mm in diameter were collected for the determination of N, P, Mg and K concentrations. Five, 8, and 14 tree and bush species occurred in the pastures of Itambé, Caruaru and Serra Talhada respectively. In Itambé, N content was influenced by species, while P and K contents were affected by species and season. In Caruaru, N, P and K contents were not influenced by season and in Serra Talhada, only P and K contents were influenced by species and season. Chemical composition was generally more adequate in the rainy season.<hr/>O objetivo desse trabalho foi avaliar nos períodos seco e chuvoso de cada região a composição mineral de espécies arbóreas e arbustivas ocorrentes em áreas de pastagem dos Municípios de Itambé, Caruaru e Serra Talhada, nas zonas fisiográficas Mata, Agreste e Sertão de Pernambuco. Foram coletadas folhas e galhos com até 5,0 mm de diâmetro, para a determinação dos teores de N, P, Mg e K. Foram encontradas, respectivamente 5, 8 e 14 espécies arbustivas arbóreas nas pastagens estudadas de Itambé, Caruaru e Serra Talhada. Para Itambé, o teor de N variou conforme a espécie, enquanto que o P e K variaram conforme a espécie e época do ano. As espécies encontradas em Caruaru, não sofreram influência da época de coleta para N, P e Mg. Em Serra Talhada apenas P e K sofreram interação época do e ano e espécie. As espécies analisadas apresentaram em geral composições químicas mais satisfatórias no período chuvoso. <![CDATA[<b>Digestive enzymes in grass carp juveniles fed with forage and ration</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300045&lng=en&nrm=iso&tlng=en Objetivou-se avaliar a atividade de enzimas digestivas de 240 juvenis (20,15±0,23 g) de carpa capim (Ctenopharyngodon idella) alimentadas com capim teosinto e ração durante 45 dias e criados em sistema de recirculação de água, composto por 12 tanques (20 peixes/tanque). Os tratamentos foram: C= somente capim teosinto; SD= capim teosinto+ração diariamente (3% PV); SA= capim teosinto+ração a cada dois dias (3% PV); R= somente ração (3% PV). Após o período de alimentação, 6 peixes por tratamento foram abatidos para análise (na porção anterior e posterior do trato) das enzimas digestivas amilase, maltase, tripsina e quimiotripsina. Também foram avaliados os pesos do fígado, do trato digestório, comprimento do trato e ganho em peso relativo. A associação de capim e ração, diariamente, resulta em maior peso do fígado, ganho em peso relativo e menor atividade de maltase. A atividade de amilase, o peso e comprimento do trato digestório não variaram (p>0,05). A atividade das proteases alcalinas é menor quando juvenis de carpa capim são alimentadas exclusivamente com ração.<hr/>The activity of digestive enzymes of grass carp (Ctenopharyngodon idella) juveniles fed with teosinte grass and ration during 45 days was evaluated in 240 juveniles (20.15±0.23 g), reared in 12 water recirculating tanks (20 fish/ tank). The treatments were: C= only teosinte grass; SD= teosinte grass+daily supplementation (3% BW); SA= teosinte grass+supplementation every two days (3% BW); R= only ration (3% BW). After the feeding period, 6 fish per treatment were killed for analysis (in anterior and posterior intestine) of digestive enzymes: amylase, maltase, trypsin and chymotripsin. The weights of liver and digestive tract, tract length and relative weight gain also were evaluated. The association of grass and ration, daily, Results in higher liver weight and relative weight gain and lower maltase activity. It was not observed effect (p>0.05) in amylase activity, weight and length of tract. Alkaline proteases activities are lower when grass carp juveniles fed only ration. <![CDATA[<b>Markers for estimate beef cattle digesta flow</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300046&lng=en&nrm=iso&tlng=en O objetivou-se comparar os métodos de único e duplo indicador na estimativa do fluxo de digesta duodenal e omasal em 7 novilhos Nelore (peso medio 250 kg), canulados no rúmen e duodeno. Os animais receberam via infusão ruminal contínua por bomba solução contendo CoEDTA. Também receberam uma cápsula contendo Cr2O3 através da cânula ruminal, e uma cápsula contendo alcanos externos C32, C36. Indicadores internos fibra em detergente neutro e fibra em detergente ácido (FDNi e FDAi após 144 h de incubação in situ) e alcanos internos C31, C33, C35 eram parte integrante da dieta. Os novilhos foram alimentados comBrachiaria brizantha cv. marandu aos 30 ou 60 dias de rebrota. O desenho experimental para o fluxo duodenal foi em esquema fatorial 2x2x12 e na estimativa do fluxo de digesta omasal o esquema fatorial foi 2x2x4. Na estimativa do fluxo duodenal de MS os indicadores FDNi, CoEDTA e a combinação Co+FDNi foram eficientes na estimativa do fluxo omasal de MS se mostraram eficientes os indicadores FDNi, FDAi e a combinação Co+FDAi. O método de coleta de duplo indicador é o mais adequado para estimativa de fluxo considerando-se a digestibilidade ruminal da fibra.<hr/>The duodenal and omasal dry matter flows by single and double marker methods were compared in seven Nellore steers with average body weight 250 kg, and previously canullated in the rumen and duodenum. The animals were fitted with continuous-infusion pump that administered CoEDTA solutions intraruminally. In addition, a capsule containing Cr2O3, and other, containing external n-alkanes C32, C36 were inserted into the rumen of each steer. Internal markers indigestible neutral-detergent fiber and acid-detergent fiber (iNDF and iADF after 144 h in situ incubation) and internal n-alkanes C31, C33, C35 were components of the diet. Steers were fed with palisade grass (Brachiaria brizantha cv. marandu) in two age of regrowth, 30 and 60 days. The duodenal flow experimental design was a factorial 2x2x12 while omasal experimental design was a factorial 2x2x4. Markers iNDF, CoEDTA and the combination Co+iNDF were efficacious to estimate duodenal dry matter flow whereas iNDF, iADF and the Co+iADF combination were all efficacious to predict omasal dry matter flow. In Conclusion, the double marker method for estimation of omasal and duodenal dry matter flow was the most appropriate considering the ruminal fiber digestibility. <![CDATA[<b>Profiting coffee residue in feeding of Nile tilapia</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300047&lng=en&nrm=iso&tlng=en O trabalho propôs avaliar formas de inclusão de resíduos de café na ração para alimentação de tilápia do Nilo. Foram realizados três ensaios: 1-composição química das rações; 2-digestibilidade das rações e 3-desempenho de tilápias recebendo as rações contendo diferentes formas de inclusão dos resíduos de café. Foram testados os seguintes tratamentos: T1-ração referência; T2-ração com resíduo de café pré-seco em estufa; T3-ração com resíduo de café mantido em condições aeróbicas acrescido de soro de leite e melaço; T4ração com silagem ácida de resíduo de café com ácido fórmico; T5-ração com silagem de resíduo de café com soro de leite. Esses resíduos substituíram 30% da ração referência, sendo as rações posteriormente peletizadas. O tratamento T5 foi o que resultou em maior ganho de peso e consumo de ração. Os tratamentos T1 e T2 não diferiram entre si, apresentando valores próximos ao T5. Os tratamentos T6 e T7 apresentaram menor ganho de peso e consumo de ração e ainda maior conversão alimentar.<hr/>This work evaluated different ways to include residues from coffee in Nile tilapia ration. Three assays were conducted: 1-rations chemical composition; 2-digestibility and 3-tilapia performance fed with different ways to include residues of coffee on ration. The following treatments were tested: T1-basal ration; T2-stove pre-dried coffe residue ration; T3-ration with residue from coffee maintained under aerobic conditions added serum of milk and nolasses; T4-ration with acid ensilage of residue from coffee with formic acid; T7-ration with ensilage of residue from coffee with serum of milk. Those residues replaced 30% of the basal ration. The physical form of the ration was pelleted. The treatment T5 resulted in greater weight gain and feed consumption and lesser feed conversion. The treatments T1 and T2 did not defer between itself presenting close values to the T5. The treatments T6 and T7 presented lesser weight gain and ration consumption and greater feed conversion. <![CDATA[<b>Development of an eight-plex SNP assay associated with milk production</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300048&lng=en&nrm=iso&tlng=en Los altos niveles de producción alcanzados en la explotación animal se deben en gran medida al trabajo de selección que se ha desarrollado en las principales especies de interés económico. El empleo de la información molecular en los programas de selección asistida ha abierto un amplio campo en la mejora animal. Se describe la metodología empleada para el genotipado simultáneo de los genes que codifican para las seis principales proteínas lácteas, la hormona del crecimiento y prolactina bovinas. Fueron utilizadas tres técnicas para el genotipado: digestión con enzimas de restricción, secuenciación y minisecuenciación para determinar SNPs (Single Nucleotide Polymorphisms), donde las dos primeras se usaron como control de los resultados obtenidos por minisecuenciación. Esta última metodología permite la automatización del análisis, el trabajo simultáneo con varias muestras y 10 o más marcadores en una sola reacción. Se observó que los genes que codifican para αs2-caseína y prolactina se comportaron monomórficos. Para la as1-caseína se identificaron los alelos B y C; en la β-caseína se identificaron los alelos A y B; por otra parte para la k-caseína fueron los alelos A y B los observados. En la α-lactoalbúmina y β-lactoglobulina se identificaron los alelos A y B, mientras que para la hormona del crecimiento se observaron los alelos L y V. En todos los casos resultaron ser los alelos que con mayor frecuencia se describen. Se corroboró que la técnica de minisecuenciación simplifica el análisis y es útil en la caracterización molecular dirigida a una futura selección asistida por marcadores.<hr/>High production levels achieved in animal exploitation is due largely to the selection work that has developed in the main species of economic interest. The use of the molecular information in the programs of assisted selection has opened a big field in the animal improvement. The methodology for the simultaneous genoptyping of the genes that encode the six major milk proteins, growth hormone and bovine prolactin is described. Three techniques were used for genotyping: restriction enzyme digestion, sequencing and minisequencing to determine SNPs (Single Nucleotide Polymorphisms), where the first two were used as control to the Results of minisequencing. This latter methodology enables the automation of analysis, simultaneous work with several samples and ten or more markers in a single reaction. It was found that the genes encoding for αs2-casein and prolactin behaved as monomorphic. For the αs1-casein the alleles B and C were identified; in the β-casein the alleles A and B were identified; on the other hand for the kcasein the alleles A and B were the observed ones. In the a-lactoalbumin and β-lactoglobulin the alleles A and B were identified, moreover for the growth hormone, alleles L and V were observed. In all cases the most frequent alleles are the described ones. It was confirmed that the minisequencing technique simplifies the analysis and it is useful for the molecular characterization focused a future targeted molecular markerassisted selection. <![CDATA[<b>Genetic diversity of Albanian goat breeds based on microsatellite markers</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300049&lng=en&nrm=iso&tlng=en The domestic goat is one of the most important livestock species in mountainous area of Albania. In this study thirty microsatellite markers in 183 unrelated individuals from 6 local goat breeds are analyzed. Twenty nine markers had five or more alleles. All loci were polymorphic and a total of 331 alleles were detected. The average number of alleles per locus was 11.03. Within breeds, the mean number of alleles ranged from 7.8 to 8. Mean expected heterozygosity (He) ranged from 0.712 to 0.758. Allelic richness varied from 7.61 to 8.19. Inbreeding for all population is rather high F IS= 0.093, ranging from 0.075 to 0.103. The mean F ST (˜ 0.02) demonstrated that 98% of total genetic variation is due to genetic differentiation within each population.<hr/>La cabra doméstica es una de las especies ganaderas más importantes en la zonas montañosas de Albania. En este trabajo se analizaron 30 marcadores microsatélites procedentes de 183 individuos no relacionados, pertenecientes a 6 razas locales de cabras. Veintinueve marcadores mostraron 5 o más alelos. Todos los loci fueron polimórficos habiéndose detectado un total de 331 alelos. El número medio de alelos por locus fue 11,03. Dentro de las razas, el número medio de alelos osciló entre 7,8 y 8. La heterocigosidad media esperada (He) osciló entre 0,712 y 0,758. La riqueza alélica varió de 7,61 a 8,19. La consaguinidad para toda la poblacón es más bien alta F IS= 0,093 con un rango de 0,075 a 0,103, la F ST media (˜ 0,02) demostró que el 98% de la variación genética total se debe a la diferenciación genética dentro de cada población. <![CDATA[<b>Stepwise vitrification of <i>in vitro</i> produced buffalo Blastocysts</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300050&lng=en&nrm=iso&tlng=en The purpose of this study was to evaluate the use of a stepwise vitrification as a method for cryopreservation of in vitro-produced (IVP) buffalo blastocysts and to compare the results with post-thaw survival rate of buffalo blastocysts frozen by stepwise vitrification with those frozen by conventional vitrification (one step method). Selected IVP blastocysts were exposed to a vitrification solution consisting of 40% ethylene glycol (EG) plus 0.3 M trehalose and 20% polyvinyl pyrrolidone (PVP) for 1 min and loaded in 0.25 ml plastic mini straws containing 100 μl of 10% sucrose. The loaded cryostraws were cryopreserved by either the stepwise vitrification or one step vitrification and stored in liquid nitrogen for one month. After thawing and removal of cryoprotectants, embryos exhibiting intact zona pellucida and uniform blastomeres were considered suitable for in vitro culture. Of the embryos cryopreserved by stepwise and one step vitrification, 100 and 60%, respectively, recovered embryos post-thawing. Similarly 95.4 and 71.1% of embryos cryopreserved by stepwise and one step vitrification were exhibiting good embryos post-thawing. Post-thaw blastocysts were serially washed in tissue culture medium 199 (TCM-199) for 5 min in both cases. They were then cultured in TCM-199 supplemented with 10% fetal calf serum for 2448 h. Development to hatched blastocyst stage was considered the initial indicator of success of cryopreservation of embryos. The rates of blastocyst re-expansion and hatching of stepwise vitrified blastocysts (66 and 55%, respectively) were significantly higher (p<0.01) than the corresponding values with one step method (40% and 20%, respectively) and it was nearly similar to that of the control group (68% and 58%, respectively). This is the first report on stepwise vitrification of buffalo embryos. Present results suggest that stepwise vitrification supports better in vitro survival of frozen thawed buffalo embryos.<hr/>El propósito de este estudio fue evaluar el uso de la vitrificación por etapas como un método para la críopreservacion de blastocistos de búfalo producidos in vitro (IVP) y comparar sus resultados con los de de blastocistos congelados por el método convencional de vitrificación en una etapa. Blastocistos (IVP) seleccionados fueron expuestos a una solución de vitrificación base de 40% de etilenglicol (EG) más trealosa 0,3 M y 20% de polivinil pirrolidona (PBP) durante un minuto y cargada en minipajuelas de plastico de 0,25 ml que contenian 100 ml de sucrosa al 10%. Las criopajuelas cargadas fueron críopreservadas mediante la vitrificación por etapas o por la vitrificación de una etapa y almadenadas en nitrógeno líquido durante un mes. Después de la descongelación y eliminación de los críoprotectores, fueron considerados adecuados para el cultivo in vitro, los embriones que mostraban una zona pellucida intacta y blastómeros uniformes. De los embriones críopreservados, mediante vitrificación por etapas o de un aetapa, el 100 y 60% respectivamente, fueron recuperados después de la descongelación. Del mismo modo, 95,4 y 71,1% de los embriones críopreservados por ambos métodos, exhibieron fueron buenos después de la descongelación. Los blastocistos postdescongelados, fueron lavados de manera seriada con medio de cultivo de tejidos 199 (TCM-199) durante 5 minutos en ambos casos. A continuación, fueron cultivados en TCM-199 suplementado con 10% de suero fetal de ternero durante 24-48 horas. La incubación hasta la etapa de blastocitos, se consideró el indicador inicial de éxito en la críopreservacion de los embriones. Las tasas de re-expansión e incubación de los blastocistos vitrificados por etapas (66 y 55%, respectivamente) fueron mayores (p<0,01) que los valores correspondientes al método de una etapa (40 y 20% respectivamente) y fueron muy parecidos a los del grupo control (68 y 58% respectivamente). Este es la primera comunicación sobre la vitrificación por etapas en búfalos. Los resultados obtenidos sugieren que la vitrificación por etapas favorece mejor la supervivencia in vitro de los embriones de búfalo descongelados. <![CDATA[<b>Chemical composition of sugarcane bagasse ammoniated with different levels of urea and whole soybean</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300051&lng=en&nrm=iso&tlng=en Objetivou-se com este trabalho avaliar o efeito de diferentes doses de uréia e soja grão moída, como fonte de urease, sobre a composição química do bagaço de cana-de-açúcar amonizado. Utilizaram-se quatro doses de uréia (2, 4, 6 e 8% MS) e três doses de soja grão moída (0; 2 e 4% MS) no bagaço de cana-de-açúcar armazenado por um período de 52 dias, em sacos de polietileno com capacidade de 50 litros. Foram analisados os teores de MS, PB, FDN, FDA, hemicelulose, celulose e lignina. Foi utilizado delineamento experimental inteiramente casualizado com três repetições por tratamento. O aumento das doses de uréia no processo de amonização do bagaço de cana-deaçúcar implicou em redução dos teores de FDN, FDA, celulose, hemicelulose e lignina, e aumento dos teores de PB. Todavia, os teores de MS não foram afetados pelas diferentes doses de uréia e soja grão moída utilizadas nos tratamentos, diferindo apenas da MS do bagaço de cana in natura. A utilização da soja grão moída, como fonte de urease, na amonização do bagaço de cana-de-açúcar, foi eficiente na redução dos níveis de FDN apenas para as doses de 2 e 4% de uréia.<hr/>The objective of this work was to evaluate the effect of the different levels of urea and ground whole soybean as a urease source on the chemical composition of the ammoniated sugarcane bagasse. Four levels of urea (2%, 4%, 6% e 8% DM) and three levels of ground whole soybean (0%; 2% e 4%, DM) were added to sugarcane bagasse stored during 52 days in plastic bags (50 L). We analyzed the levels of DM, CP, NDF, ADF, cellulose, hemicellulose and lignin. Was used a complete randomized design with three replicates for treatments. The gradual increase of the urea levels in the process of amonização of sugarcane bagasse implied in reduction of NDF, ADF, cellulose, hemicellulose and lignin, and increase of CP. However, the levels of DM were not affected by different levals of urea and whole soybean used in different treatments, differing only in the DM ofin nature sugarcane bagasse. The use of ground whole soybean, as source of urease, in the amonização of sugarcane bagasse, was efficient in the reduction of the levels of NDF only for the levels of 2 and 4% of urea. <![CDATA[<b>Chemical composition and <i>in vitro</i> gas production of diets with <i>Acacia farnesiana</i> pods</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300052&lng=en&nrm=iso&tlng=en Se valoró el efecto de la inclusión de vainas de Acacia farnesiana en dietas para corderos. Los niveles de A. farnesiana en los tratamientos fueron 0, 100, 200, 300 y 400 g/kg MS en dietas isoprotéicas para corderos en crecimiento que incluyeron rastrojo de maíz, harina de soya, salvado de trigo y mezcla de minerales. Las vainas aportan una importante cantidad de proteína (115 g/kg); de taninos (7,8 g/kg). La producción de gas in vitro disminuyó (p<0,05) con la inclusión de 400 g/kg (304,45 ml/g MS); no obstante, fue similar a 300 g/kg (317,88 ml/g MS). La desaparición de la materia seca in vitro fue semejante en 0 y 100 g/kg con 70,14 y 68,73 mg/100 mg MS respectivamente; no obstante, ambas fueron diferentes al resto de los tratamientos. La producción de gas relativa fue similar entre 200 a 400 g/kg, aunque diferentes a la dieta control. Inclusión de 300 g/kg MS de vainas de A. farnesiana impacta negativamente en la producción de gas y energía metabolizable, y a partir de 200 g/kg MS afecta la desaparición de la materia seca y la producción de gas relativa in vitro lo cual podría limitar su uso y aprovechamiento para la alimentación de rumiantes.<hr/>The inclusion of Acacia farnesiana pods into lamb diets was evaluated by means of analyzing its chemical composition, tannin content and in vitro gas production, dry matter disappearance and metabolizable energy. The treatments with different inclusion levels of A. farnesiana pods were 0, 100, 200, 300 and 400 g/kg DM, within isoprotein diets for lambs which included ground maize fodder, soybean meal, wheat bran and mineral mix. The A. farnesiana pods contributed with an important amount of protein (115 g/kg), and tannins (7.8 g/kg). in vitro gas production decreased (p<0.05) with the inclusion of 400 g/kg DM (304.45 ml/g DM); nonetheless, its production was similar to 300g/kg (317.88 ml/g DM). in vitro dry matter disappearance (IVDMD) in 0 and 100 g/ kg was similar between them with 70.14 and 68.73 mg/100 mg DM respectively; however, they were different than the rest of the treatments. Relative gas production was similar between 200 to 400 g/ kg, nevertheless it was different to control diets. It is concluded that the inclusion of 300 g/kg DM of A. farnesiana pods has a negative impact over in vitro gas production and metabolizable energy, and over 200 g/kg DM affect the dry matter disappearance and relative in vitro gas production, which limit its use for feeding ruminants. <![CDATA[<b>Performance response of grazing lactating dairy cows to chopped fresh maize as supplement</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300053&lng=en&nrm=iso&tlng=en A 24 vacas Holstein multíparas en pastoreo rotacional en una pradera mixta alfalfa-pasto ovillo, se suministraron: 0, 4 y 8 kg de MS de maíz fresco picado (MFP) animal-1día-1. Además, cada animal recibió 3,8 kg de MS de alimento concentrado. Se utilizó un diseño reversible simple (crossover) (tres tratamientos, dos repeticiones con cuatro animales cada uno), de 3 períodos, con una duración de 19 días cada uno (10d de adaptación y 9d de muestreo). No hubo diferencias significativas en producción individual ni en composición de la leche. El consumo de pradera disminuyó (p<0,0001) de 8,4 a 5,2 y 3,1 kg de MS de pradera al aumentar el nivel de MFP de 0 a 4 y 8 kg de MS, respectivamente; mientras que el consumo total de MS incrementó (p<0,0001) en aquellas vacas con un nivel de suplemento más alto, promediando 12,2, 12,9, y 14,8 kg de MS total con 0,4 y 8 kg de MS de MFP, respectivamente. La tasa de sustitución fue de 0,75 y 0,67 kg de MFP con 4 y 8 kg de MS de MFP respectivamente, consecuentemente incrementó (p<0,0001) la carga animal (CA), de 3,8 a 6,2, y 8,8 vacas ha-1 al aumentar de 0 a 4 y 8 kg de MS de MFP, respectivamente, mientras que la producción de leche por hectárea incrementó (p<0,0001) de 39,3 a 64,5 y 95,5 kg de leche, respectivamente. Esto indica que por cada kg de MS de MFP, la CA aumenta 0,63 vacas y 0,75 kg de leche ha-1. La suplementación con MFP a vacas en etapa final de lactancia no presentó beneficios en producción de leche individual, ni cambios en composición de la leche, pero sí incrementó la producción de leche por hectárea, como resultado de aumento en la CA.<hr/>Twenty four multiparous Holstein dairy cows were rotationally grazed on a mixed alfalfaorchard sward. Three treatments were evaluated: 0, 4, and 8 kg of DM of MFP cow-1 day-1. Each cow received 3.8 kg of concentrate (DM basis). The experimental design was a cross-over (3 treatments, 2 replicates with 4 animals each), with 3 periods lasting 19 days each (10 adaptation plus 9 sampling period). There were no differences on individual milk production nor on milk composition. Herbage dry matter intake decreased (p<0.0001) from 8.4 to 5.2 and 3.1 kg of DM when increasing MFP from 0 to 4 and 8 kg of DM, respectively; while total DM intake increased (p<0.0001) on those cows with the highest level of supplementation, averaging 12.2, 12.9, 14.8 kg of total DM at 0, 4, and 8 kg of DM of FCM, respectively. Substitution rate of pasture for MFP was 0.75 and 0.67 kg of pasture per kg of FCM with 4 and 8 kg of DM of MFP, respective. Consequently, stocking rate (STR) increased (p<0.0001) from 3.8, to 6.2, and 8.8 cows ha-1, with 0, 4, and 8 kg of DM of MFP, respectively; and milk production per hectare increased (p<0.0001) from 39.3 to 64.5 and 95.5 kg of milk with 0, 4, and 8 kg of DM of FCM, respectively. This means that STR increases 0.63 cows ha-1, and 0.75 kg of milk when MFP is increased in one kg of DM. It is suggested that offering MFP as supplement to grazing dairy cows in their final lactation stage had no benefits in individual milk production or milk composition; but on milk production per hectare. <![CDATA[<b>Effects of ractopamine on performance and physiology of pigs</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300054&lng=en&nrm=iso&tlng=en O objetivo deste trabalho foi avaliar a inclusão de diferentes níveis de ractopamina em rações de suínos em fase de terminação, durante 21 dias pré-abate, sobre as características de desempenho, carcaça, qualidade de carne e sobre parâmetros fisiológicos e sanguíneos indicadores de bem-estar. Foram utilizados 36 suínos comerciais, 18 machos castrados e 18 fêmeas, com peso médio inicial de 87,0±5,02 kg, alimentados ad libitum com rações isonutrientes, com 0, 10 e 20 ppm de ractopamina. O delineamento experimental foi em blocos casualizados, fatorial 3 x 2, com seis repetições para os parâmetros de desempenho e 12 repetições para os demais parâmetros. Houve efeito linear (p<0,05) positivo para o ganho de peso e para a conversão alimentar e efeito quadrático (ponto de mínima de 9,4 ppm de ractopamina) para o consumo de ração. Para os parâmetros de carcaça houve efeito quadrático para o rendimento de carcaça (com ponto de máxima para 9,5 ppm de ractopamina). O valor de a*(componente vermelho-verde), c*(índice de saturação) e marmoreio apresentaram efeito linear negativo. O diâmetro da fibra muscular do músculo L. dorsi e o ângulo de tonalidade (h*) apresentaram efeito linear positivo para os níveis de ractopamina. Outros parâmetros relacionados à qualidade da carne não foram influenciadas pelos tratamentos, resultando em carnes livres de PSE e DFD. A ractopamina pode ser utilizada nas rações de suínos até 20 ppm com efeitos positivos no desempenho e na carcaça, sem alterações no comportamento dos animais e comprometimentos na qualidade da carne.<hr/>The goal of this work was to evaluate the inclusion of different levels of ractopamine to finishing rations for swine, during 21 days before the slaughter, on the performance, carcass and meat quality parameters and on physiologic and serum characteristics related with behavior. Thirty six pigs (Large White x Landrace), 18 barrows and 18 females, weighting 87.0±5.02 kg, fed ad libitum with isonutrient rations, with 0, 10 and 20 ppm of ractopamine, were used. The experimental design was randomized blocks, factorial 3 x 2 (3 levels of ractopamine and 2 genders), with 6 repetitions for the performance parameters and 12 repetitions for the other characteristics. There were a positive linear effect (p<0.05) to the weigh gain and to the feed conversion rate and a quadratic effect to the feed consumption (been the minimal point to 9.4 ppm of ractopamine). To the carcass parameters there was a quadratic effect to the carcass yield (been the minimal point to 9.5ppm of ractopamine). The parameters a*(red-blue component) and c*values (saturation index) and marbling presented a negative linear effect according to the levels of ractopamine. The fiber diameter of the L. dorsi muscle and the tonality angle index (h*) showed a positive linear effect to the levels of ractopamine. There were no effects on the other meat quality characteristics, resulting meats without PSE and DFD. The ractopamine can be used until 20 ppm with positive effects on the performance and carcass parameters, without effects on the behavior and on meat quality. <![CDATA[<b>Effect of the ratio between carried and body weight on finishing time in thoroughbreds</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300055&lng=en&nrm=iso&tlng=en Since the racehorses with excellent performance have a heavy carried weight (CW) in the current system, their finishing time does not increase along with heavier CW. As the CW increases, the finishing time decreases. Moreover, the percentage of victories also gets higher as the CW increases. Therefore, the effect of ratio CW/ BW as the ratio of carried weight to the body weight on finishing time was analyzed in order to suggest the problems of current CW system. The objective of this study is to examine the influence of CW/BW ratio on finishing time, using a total of 155 656 racing records belong to 8197 racehorses. Generally, the BW of racehorse is heavier, the potentiality as a good racehorse is higher. The fact that the ratio CW/BW is high means that most of racehorses have lighter BW. As the ratio CW/BW increases in the racing distance of 1000 m, the actual finishing time tends to increase in general. The finishing time that has run while bearing the ratio of 12.0-12.7%, has demonstrated a good racing record. When the ratio CW/BW is about 13.1% or more, it has begun to influence on the finishing time gradually. Also, the racehorse tends to have a growth potential in a long distance race when the BW is no less than 475-480 kg. Consequently, when setting a handicap, it is desirable to consider the just before raced BW of racehorse to a certain degree.<hr/>Dado que los caballos de carrera con excelentes prestaciones transportan un handicap pesado (CW) en el sistema actual, su tiempo a la finalización no aumenta con handicaps (CW) aún mayores. Cuando el CW aumenta, el tiempo de carrera disminuye. Por otra parte, el porcentaje de victorias se hace mayor a medida que aumenta el CW. Por ello, el efecto de la relación CW/BW, como relación entre peso transportado y peso corporal, sobre el tiempo de la carrera fue analizado al objeto de detectar los problemas en el sistema actual de handicap. El objetivo de este estudio fue examinar la influencia de la relación CW/BW, sobre el tiempo de carrera, empleando un total de 155 656 registros pertenecientes a 8197 carreras. Generalmente si el peso corporal del caballo es más pesado, su potencial como buen caballo de carrera es mayor. El hecho de que la relación CW/BW sea alta, significa que el peso de los caballos es menor. Cuando la relación CW/BW aumenta en la distancia de 1000 m el tiempo de la carrera tiende a aumentar. Cuando la relación está entre 12,012,7%, se ha demostrado conseguir un buen tiempo de carrera. Cuando la relación CW/BW es de 13,1 o más, comienza a influir gradualmente sobre el tiempo de carrera. También el caballo tiende a tener un buen potencial de recuperación en una distancia larga cuando el BW no es inferior a 475-480 kg. Consecuentemente cuando se asigna un handicap, es deseable tener en cuenta el peso del caballo antes de la carrera. <![CDATA[<b>Phytobiotic additives and sodium butyrate as growth promoters of weanling pigs</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300056&lng=en&nrm=iso&tlng=en O objetivo do trabalho foi estudar os efeitos de aditivos fitogênicos e butirato de sódio como alternativas aos antimicrobianos promotores de crescimento sobre o desempenho, digestibilidade, pH do conteúdo digestório e frequência de diarréia de leitões recém-desmamados. Um experimento em blocos casualizados completos, com duas repetições no tempo e 34 dias de duração cada, foi realizado para testar cinco tratamentos: controle (T1) dieta basal; antimicrobiano (T2) basal com 40 ppm de sulfato de colistina; fitogênico (T3) dieta basal com 500 ppm de aditivos fitogênicos microencapsulados; butirato de sódio (T4) dieta basal com 1500 ppm de butirato de sódio; fitogênico + butirato de sódio (T5) dieta basal com 500 ppm de aditivos fitogênicos + 1500 ppm de butirato de sódio. Para o desempenho e a frequência de diarréia, foram utilizados 120 leitões, oito repetições por tratamento e três animais por unidade experimental. A digestibilidade foi determinada em 60 leitões das quatro primeiras repetições, utilizan-do-se o método da coleta parcial de fezes e o óxido de cromo como marcador. Ao final do período experimental, um animal de cada baia, das quatro primeiros repetições, foi abatido para mensuração do pH do duodeno, jejuno e ceco. Foram testados contrastes específicos de importância prática. Embora, o desempenho dos leitões não tenha sido influenciado pelos tratamentos (p>0,05), o tratamento butirato de sódio (T4) apresentou os melhores resultados numéricos em ambos os períodos analisados. Também não houve diferença (p>0,05) entre os tratamentos para a frequência de diarréia e para o pH da digesta. Os leitões dos tratamentos fitogênico (T3) e butirato de sódio (T4) apresentaram a média de coeficiente de digestibilidade aparente da energia superior (p=0,07) ao dos leitões do tratamento fitogênico + butirato de sódio (T5). Assim, em condições de creche experimental, não ficou evidenciado qualquer efeito dos aditivos fitogênicos e do butirato de sódio como promotores de crescimento de leitões recém-desmamados alimentados com dietas complexas e altamente digestíveis.<hr/>The purpose of this work was to evaluate phytobiotic additives and sodium butirate as alternatives to antimicrobial growth promoters based on performance, digestibility, digesta pH and diarrhea incidence of weanling pigs. A 34-d randomized complete block design experiment, two replicates in the time, was carried out to compare five treatments: control (T1) basal diet; antimicrobial (T2) basal diet with 40 ppm of colistin sulfate; phytobiotic (T3) basal diet with 500 ppm of microencapsulated natural phytobiotics; sodium butyrate (T4) basal diet with 1500 ppm of sodium butyrate; and phytobiotic + sodium butyrate (T5) basal diet with 500 ppm of natural ptytobiotics + 1500 ppm of sodium butyrate. One hundred and twenty piglets, eight replications per treatment, and three animals per experimental unit were used for performance data and diarrhea incidence. For digestibility assay, 60 piglets of first four replications were considered, using chromium oxide as fed marker. At the end of experimental period, an animal per pen of first four replications was slaughtered for digesta pH measurements. Specific contrasts of practical importance were tested. No differences were found in performance data (p>0.05), however numerically sodium butyrate (T4) showed the best results in both periods. The treatments did not show any effect (p>0.05) on diarrhea incidence and on digesta pH. Energy digestibility coefficient average of phytobiotic additives (T3) and sodium butyrate (T4) was higher (p= 0.07) than that of phytobiotic + sodium butyrate (T5). Therefore, in the experimental nursery condition, there was no evidence of natural phytobiotic and sodium butyrate as growth promoters of weanling pigs fed complex diet with high digestibility raised. <![CDATA[<b>Efects of essential oils as growth promoters on performance of weaned pigs</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300057&lng=en&nrm=iso&tlng=en Objetivou-se avaliar o efeito de antibiótico e óleos essenciais sobre a digestibilidade das rações e desempenho de leitões recém-desmamados. Foram realizados dois experimentos, utilizando o delineamento em blocos casualizados, com cinco tratamentos (T1: controle - ração basal; T2: basal + antibiótico (0,2%); T3, T4 e T5: basal + 0,02; 0,04 e 0,06% de Tecnaroma Herbal (TH), respectivamente), quatro repetições e três animais por unidade experimental (desempenho) e um animal por unidade experimental (digestibilidade). O desempenho foi determinado com 60 leitões e a digestibilidade utilizando 20 leitões. O TH é um produto comercial constituído por sete tipos de óleos essenciais (aniz, aniz estrelado, tomilho, orégano, alho, eucalipto (globulus e citriodora) e ginepro. O maior nível de inclusão do TH (T5) foi o que proporcionou os melhores resultados de desempenho. Os animais do tratamento controle foram os que apresentaram os piores resultados. Os tratamentos contendo os dois maiores níveis de inclusão dos óleos essenciais determinaram maior digestibilidade dos contituintes da ração. Os resultados encontrados nesta pesquisa sugerem que o produto TH pode, com grandes chances de sucesso, ser utilizado como aditivo alternativo aos agentes antimicrobianos como promotores do crescimento de leitões.<hr/>Two trials were conducted to evaluate the effects of antibiotic and essential oils on diets digestibility and performance in weaned pigs. Sixty weaned pigs (in performance trial) and twelve piglets (in digestibility trial), in a randomized block design, were used to compare five treatments: T1: control - basal diet; T2: basal diet + antibiotic (0,2%); T3, T4 e T5: basal diet + 0,02; 0,04 e 0,06% essential oil (TH), respectively, with four replications and three pigs per experimental unit (performance) and one pig per experimental unit (digestibility). The Tecnaroma Herbal (TH) is a commercial product consisted of mixture of seven types of essential oils (anise, star anise, thyme, oregano, garlic, eucalyptus and ginepro). The highest level of TH (T5) improved the performance of animals. Two highest levels of essentials oils increased dietary digestibility compared to control and antibiotic treatments. The Results of this study suggest that the product TH can be used, with great chances of success, as an additive alternate to antimicrobial agents as growth promoters for piglets. <![CDATA[<b>Molecular markers related to marbling in Uruguayan Creole cattle</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300058&lng=en&nrm=iso&tlng=en En Uruguay existe una reserva genética de bovinos Criollos ubicada en el Departamento de Rocha. Estudios previos basados en marcadores moleculares altamente polimórficos mostraron que dicha población presenta una alta diversidad genética. En la década del 60 se produjo una migración de bovinos Criollos de la reserva a establecimientos ganaderos del norte del país. Este ganado fue utilizado en cruzamientos comerciales con las razas Aberdeen Angus, Hereford, Caracú y cebuinas, estando sus productos introducidos en el mercado cárnico uruguayo. Se presentan datos de la caracterización genética de la reserva y de dos poblaciones cruza (Rivera y Cerro Largo) para tres marcadores moleculares asociados al veteado de la carne: diacilglicerol acetil-transferasa (DGAT1), tiroglobulina (TG) y leptina (LEP), así como una metodología de genotipado novedosa y eficaz para el polimorF ISmo del gen LEP mediante TETRA-ARMS PCR. La reserva de Criollos mostró una predominancia de los alelos y genotipos asociados a carne de bajo tenor graso en todos los marcadores. Las dos poblaciones cruza de Criollo con razas comerciales mostraron la misma tendencia para el gen DGAT1, pero mayores frecuencias de los alelos y genotipos que generan un incremento del veteado para TG y LEP. Los índices de diversidad genética resultaron de bajos a moderados (He mínima= 0,000 para DGAT1 en la población cruza de Rivera; He máxima= 0,632 para TG en la población cruza de Cerro Largo). No se observan diferencias significativas de los valores esperados para los parámetros poblacionales, según índices F IS y prueba de equilibrio Hardy-Weinberg, salvo en un caso (TG en el rodeo de Cerro Largo). Los valores de F ST muestran la similitud genética entre las dos poblaciones cruza y su diferenciación con respecto a la reserva de Criollos Uruguayos puros. La introgresión de razas comerciales y los objetivos de selección en pos de una mayor productividad afectaron las frecuencias de los marcadores analizados en los rodeos cruza. Por otro lado, el aislamiento reproductivo, la ausencia de selección artificial y la incidencia de la deriva y la selección natural han moldeado los parámetros genéticos de la reserva de Criollos Uruguayos.<hr/>The Uruguayan Creole cattle genetic reserve, located in the department of Rocha, has a high level of genetic variation, as previous studies using polymorphic markers showed. Cattle from this reserve were taken to commercial farms in the North of Uruguay during the 60'. These animals where used in crosses with commercial breeds (Aberdeen Angus, Hereford, Caracú) and zebu (Bos indicus) cattle for meat production. We analyzed a sample of Creole cattle from Rocha and from two crossbred populations from Northern Uruguay (Rivera and Cerro Largo) using three molecular markers associated with marbling: diacyl-glicerol acyl transferase (DGAT1), thyroglobulin (TG) and leptin (LEP). We describe a novel and cost-effective genotyping method based on TETRA-ARMS PCR for LEP polymorphism. The Creole cattle reserve showed higher frequencies of alleles and genotypes associated with low marbling scores in all markers. Both crossbred populations showed the same trend for DGAT1, but higher frequencies for alleles and genotypes associated with higher marbling in TG and LEP. Genetic diversity indexes were low to moderate (minimum He= 0.000 for DGAT1 in Rivera crossbred population; maximum He= 0.632 for TG in Cerro Largo crossbred population). No significant departures from the expected values were detected according to F IS and Hardy-Weinberg tests, except for one case (TG in Cerro Largo population). F ST values showed the high genetic similarities between both crossbred populations and their differentiation from the purebred Uruguayan Creole reserve. Genetic introgression of commercial breeds, plus selection objectives tending to increase productivity, had affected the frequencies of the markers analyzed in the crossbred populations. On the other hand, reproductive isolation, absence of artificial selection and the incidence of genetic drift and natural selection had modelled the population parameters of the Uruguayan Creole cattle reserve. <![CDATA[<b>Physical and sensory qualities parameters of spent broiler breeders meat</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300059&lng=en&nrm=iso&tlng=en O presente trabalho objetivou avaliar as qualidades físicas e sensoriais da carne de matrizes de frangos de corte de descarte submetida a diferentes tipos de temperos, embalada a vácuo e analisada no período 0, 24 horas (4ºC) e 48 horas (4ºC), e 30 dias (-15ºC). Foram utilizados 62 peitos de matrizes de descarte de frango de corte (Cobb 500), com aproximadamente 80 semanas de idade. Os peitos foram desossados, pesados e injetados com diferentes temperos, os quais foram diluídos (4%) em salmoura 7%. Utilizou-se um delineamento inteiramente casualizado em esquema fatorial 4 x 4 (4 tipos de temperos x 4 períodos de armazenamento), com 16 tratamentos e 4 repetições. As características avaliadas foram: pH, coloração, capacidade de retenção de água (%), perdas de peso na cocção (%), força de cisalhamento (gf/cm²) e análises sensoriais (sabor, textura e aceitação global). A utilização dos temperos industriais (T2 e T3) levaram a um aumento significativo do pH, menores perdas de peso no cozimento e carnes mais escuras (menores valores de L), e para os parâmetros força de cisalhamento e intensidade de amarelo a utilização de temperos não proporcionou diferenças estatísticas. Houve interação entre tipo de tempero e período de armazenamento para as características de capacidade de retenção de água, intensidade de vermelho e na aceitação global da análise sensorial, evidenciando piores resultados nas amostras sem temperos. Conclui-se que a utilização de condimentos industriais em carnes de matrizes de descarte diminuiu a perda de água e, consequentemente, aumentou a aceitação global das mesmas devido à sua maior suculência. Assim, a elaboração de produtos marinados pode representar uma boa alternativa para a utilização do peito de matrizes de descarte, agregando maior valor a estas aves no final do ciclo de produção.<hr/>The present study evaluated the physical and sensory parameters of spent broiler breeders meat, with different types of seasoning and stored on vacuum package during 0, 24 and 48 hours (4ºC) and 30 days (-15ºC). The Pectoralis major muscles (breast) of spent broiler breeders with approximately 80 weeks of age were used. The breasts were deboned, weighted and injected with different seasonings, which were diluted (4%) in 7% brine. They were distributed in a completely randomized experimental design in a 4x4 factorial arrangement (4 seasoning types and 4 storage times) with sixteen treatments and four repetitions. The pH, color, water retention capacity, cooking loss, shear force and sensory analyze (flavor, texture, global acceptance) were the evaluated characteristics. The results showed an interaction between the seasoning type and storage time in water retention capacity, red intensity and parameters of sensory analysis (global acceptance). It was concluded that the use of seasoning led to a water loss decrease and increased the global acceptance, because of its bigger juiciness. Thus, the preparation of marinated products may be a good alternative to the use of spent broiler breeder's breast, increasing its value at the end of the production cycle. <![CDATA[<b>Stability and Adaptability of <i>Pennisetum</i> sp. clones under pasture</b>: <b>Ocular spot</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300060&lng=en&nrm=iso&tlng=en Foi realizado um trabalho na Estação Experimental de Itambé, do Instituto Agronômico de Pernambuco-IPA, com o objetivo de avaliar a adaptabilidade e estabilidade de clones de Pennisetum sp. sob pastejo, considerando a incidência de Helminthosporium sp. O delineamento experimental foi de blocos ao acaso com cinco repetições e 16 tratamentos. As parcelas mediam 5x5 m com espaçamento de um metro entre linhas. A incidência de Helminthosporium sp. foi estudada por uma escala de notas conforme a presença de manchas nas folhas dos genótipos testados. Com relação à adaptabilidade dos genótipos, o Mineirão (0,31), Taiwan A 25 P 18 (0,50), SEA P 36 (0,28), SEA P 37 (0,38) e Gigante de Pinda P 73 (0,46) apresentaram coeficientes de regressão abaixo da média populacional (β1i), indicando adaptabilidade a ambientes desfavoráveis. Os genótipos Pusa Napier 1 P 25 (1,58), Pusa Napier 1 P 27 (1,55), Pusa Napier 1 P 28 (1,47), Pusa Napier 1 P 32 (1,28), Pusa Napier 1 P 33 (1,22), SEA P 35 (1,60), HV 241 (1,41) e Pioneiro (1,36) responderam melhor em ambientes favoráveis, e o Pusa Napier 1 P 31 e Roxo de Botucatu P 80 apresentaram ampla adaptabilidade. O híbrido HV 241 e o Pioneiro apresentaram desvios significativos da regressão pelo teste F (p<0,05), sugerindo instabilidade e imprevisibilidade às alterações ambientais. Os genótipos Pusa Napier 1 P 31 e Roxo de Botucatu P 80 são genótipos que apresentam ampla adaptabilidade, com resistência ao Helminthosporium sp. e comportamento estável nas condições da Zona da Mata de Pernambuco.<hr/>The work was conducted at the Experimental Station of Itambé, of the Pernambuco State Agricultural Research Enterprise, to evaluate the adaptability and stability of Pennisetum sp. clones under pasture and Helminthosporium sp. incidence. The experimental design was randomized blocks, with 5 replicates and 16 treatments. Plots measured 5x5 m with one meter between rows spacing. Helminthosporium sp. incidence was studied by note scale according to spot presence on the leaves of the studied genotypes. With regards to genotype adaptability, Mineirão (0.31), Taiwan A 25 P 18 (0.50), SEA P 36 (0.28), SEA P 37 (0.38) and Gigante de Pinda P 73 (0.46) had regression coefficients below population average (β1i), indicating unfavorable environment adaptability. Genotypes Pusa Napier 1 P 25 (1.58), Pusa Napier 1 P 27 (1.55), Pusa Napier 1 P 28 (1.47), Pusa Napier 1 P 32 (1.28), Pusa Napier 1 P 33 (1.22), SEA P 35 (1.60), HV 241 (1.41) and Pioneiro (1.36) had better response in favorable environments, and Pusa Napier 1 P 31 and Roxo de Botucatu P 80 had ample adaptability. Hybrid HV 241 and Pioneiro had significant deviations from regression by the F test (p<0.05), indicating instability and unpredictability to environmental alterations. Genotypes Pusa Napier 1 P 31 and Roxo de Botucatu P 80 had ample adaptability, with resistance to Helminthosporium sp. and stable behavior at the Forest Zone of Pernambuco. <![CDATA[<b>Phytobiotic additives and sodium butyrate as alternatives to antibiotics for weanling pigs</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300061&lng=en&nrm=iso&tlng=en Objetivando-se estudar os efeitos de aditivos fitogênicos e butirato de sódio como alternativas aos antimicrobianos promotores de crescimento na morfometria e histologia intestinal de leitões recém-desmamados aos 21 dias de idade foi realizado um experimento com 60 leitões distribuídos em delineamento de blocos casualizados completos com cinco tratamentos: controle (T1) - ração basal; com antimicrobiano (T2); com aditivos fitogênicos (T3); com butirato de sódio (T4) e com aditivos fitogênicos mais butirato de sódio (T5) e quatro repetições com três animais por repetição. Os tratamentos foram comparados por contrastes entre médias. Os leitões dos tratamentos T2, T3, T4 e T5 apresentaram menor média na relação peso:comprimento do intestino delgado (p= 0,02) do que os do tratamento controle (T1). A média dos tratamentos T3 e T4 para o peso relativo do ceco foi menor (p= 0,09) e para a densidade de vilosidades do duodeno (DV) dos leitões foi maior (p= 0,06) em relação aos do T5. Constatou-se ainda que as DV do duodeno dos leitões do T3 foram maiores (p= 0,02) que as dos leitões do T4. No jejuno, a média das DV dos leitões dos tratamentos T2, T3, T4 e T5 foi maior (p= 0,03) que a dos leitões do tratamento T1 e os leitões do T4 apresentaram maiores DV (p= 0,08) que os do tratamento T3. Os diferentes aditivos demonstraram eficácia na manutenção ou no aumento do número de vilos no jejuno. Os aditivos fitogênicos e o butirato de sódio, adicionados individualmente às rações dos animais, proporcionaram integridade morfométrica e fisiológica no intestino de leitões desmamados aos 24 dias de idade.<hr/>The purpose of this trial was to evaluate the effects of phytobiotic additives and sodium butyrate as alternatives to antimicrobial growth promoters based on organs morphometry and intestinal histology for piglets weaned at 21 days old. A 34-d randomized complete block design experiment was carried out, with sixty weanling pigs, to compare five treatments: control (T1) basal diet; antimicrobial (T2); phytobiotic (T3); sodium butyrate (T4) and phytobiotic + sodium butyrate (T5), three animals per pen (experimental unit) and four replications per treatment. Specific contrasts were tested. Organs morphometry showed that the average of treatments T2, T3, T4 e T5 for weight:length ratio of small intestine was lower (p= 0.02) than that of control treatment. The average of T3 and T4 treatments for caecum relative weight was lower (p= 0.09) and for DV of duodenum of weanling pigs was higher (p= 0.06) than that of the T5. Piglets of T3 showed higher DV (p= 0.02) than those of T4. Jejunum DV average of treatments T2, T3, T4 e T5 was higher (p= 0.03) than that of T1, and piglets of T4 showed higher DV (p= 0.08) than those of T3. The additives were effectives in keeping or improving villous number of jejunum. However, phytobiotic additives and sodium butyrate added individually in animal diets provided morphological and physiological integrity in the intestine of piglets weaned at 24 days old. <![CDATA[<b>Acidifiers as alternatives to antimicrobial growth promoter of weanling pigs</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300062&lng=en&nrm=iso&tlng=en O objetivo do trabalho foi avaliar combinações de acidificantes como alternativas aos antimicrobianos melhoradores do desempenho de leitões na fase de creche. O experimento foi em blocos casualizados, com 34 dias de duração e cinco tratamentos. Foram utilizados 160 leitões Topigs recém-desmamados, em torno de 24 dias e peso inicial de 6,69±1,82 kg. Para o período de 1 a 14 dias de experimento (24 a 38 dias de idade), os tratamentos foram: Am - dieta pré-inicial com 0,004% de sulfato de colistina; A1 - pré-inicial com 0,5% do mistura 1 (contendo ácido fórmico, 145000 ppm; ácido fosfórico, 85 000 ppm); A2 - pré-inicial com 0,15% do mistura 2 (butirato de sódio, 64 000 ppm) e 0,4% do mistura 3 (ácido láctico, 620000 ppm; ácido fórmico, 40000 ppm); A3 - pré-inicial com 0,8% do mistura 4 (ácido propiônico, 198000 ppm; ácido acético, 196000 ppm; ácido fórmico, 196000 ppm; ácido fosfórico, 21000 ppm; ácido cítrico, 8500 ppm); A4 - dieta basal com 0,6% do mistura 4 e 0,15% do mistura 5 (ácido benzóico, 590000 ppm; ácido fórmico, 70000 ppm; ácido fosfórico, 50000 ppm; ácido cítrico, 40000 ppm). Para o período de 14 a 34 dias, os tratamentos foram: Am - dieta inicial com 0,004% de sulfato de colistina; A1 - inicial com 0,3% do mistura 1; A2 inicial com 0,1% do mistura 2 e 0,3% do mistura 3; A3 - inicial com 0,6% do mistura 4; A4 - inicial com 0,5% do mistura 4 e 0,1% do mistura 5. Foram alocados quatro leitões por unidade experimental. Na fase pré-inicial, o tratamento A2 proporcionou melhor peso aos 14 dias (P14) e ganho diário de peso (GDP) que o A3, e melhor conversão alimentar (CA) que o Am. Para o período total, o A4 determinou melhor CA que o Am. Os tratamentos não afetaram a freqüência de diarréia e o pH estomacal. O A4 resultou em menor valor de pH cecal que o Am. Para morfologia intestinal o A2 proporcionou menores valores de profundidade de cripta (PC) do jejuno que o A3 e o Am e maior relação altura de vilosidade:profundidade de cripta do jejuno que o A1 e o A3. Os acidificantes são uma alternativa promissora aos antimicrobianos promotores do crescimento de leitões na fase de creche.<hr/>The purpose of this work was to evaluate several acidifier blens as alternatives to antimicrobial growth promoters of weanling pigs. A 34-d randomized complete block design experiment was carried out to compare five treatments using one hundred and sixty Topigs 24d-weaned pigs, with 6.69±1.82 kg live weight. For 1-14 d experimental period (24 to 38 days old), the treatments were: Am - pre-starter diet with 0.004% of colistin sulfate; A1 - pre-starter diet with 0.5% of blend 1 (containing formic acid, 145000 ppm; phosphoric acid, 85000 ppm); A2 - pre-starter diet with 0.15% of blend 2 (butyric acid, 64000 ppm) and 0.4% of blend 3 (lactic acid, 620000 ppm; formic acid, 40 000 ppm); A3 - pre-starter diet with 0.8% of blend 4 (propionic acid, 198000 ppm; acetic acid, 196000 ppm; formic acid, 196000 ppm; phosphoric acid, 21000 ppm; citric acid, 8500 ppm); and A4 - pre-starter diet with 0.6% of blend 4 and 0.15% of blend 5 (benzoic acid, 590000 ppm; formic acid, 70000 ppm; phosphoric acid, 50000 ppm; citric acid, 40000 ppm). For 1434 d experimental period, the treatments were: Am - starter diet with 0.004% of colistin sulfate; A1 starter diet with 0.3% of blend 1; A2 - starter diet with 0.1% of blend 2 and 0.3% of blend 3; A3 starter diet with 0.6% of blend 4; and A4 - starter diet with 0.5% of blend 4 and 0.1% of blend 5. The pigs were allotted to 20 suspended pens, with four pigs per experimental unit. For 1-14 d experimental period, treatment A2 gave better body weight at 14th day (BW14) and average daily gain (ADG) than A3, and better feed conversion (FC) than Am. For total experimental period (1-34 d), A4 gave better FC than Am. Treatments did not affect diarrhea frequency and stomach pH. Treatment A4 gave lower pH value than Am. For intestinal morphology, A2 provided smaller jejunum crypt depth (CD) than A3 and Am, and bigger ratio of jejunum villus height:crypt depth than A1 and A3. The acidifiers are a potential alternative to antimicrobial growth promoter for weanling piglets. <![CDATA[<b>Carcass quality and cost-benefit of rabbits fed cassava peel meal</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300063&lng=en&nrm=iso&tlng=en A study was conducted to assess the effects of dietary inclusion of processed cassava peel meals (CPM) on the carcass characteristics, meat quality and economy of production of thirty-two growing rabbits. The rabbits, aged 6-week old with an initial average weight of 567±23 g, were allocated to a completely randomized design in a 9-week experiment. There were four diets consisting of a control (without cassava peel meal) and 200 g kg-1 of ensiled cassava peel meal (ECPM), sun-dried cassava peel meal (SCPM) and retted cassava peel meal (RCPM), respectively. The hydrogen cyanide (HCN) contents of processed CPM followed this rank order: RCPM (98.10mg/kg)< SCPM (165 mg/kg)< ECPM (299.21 mg/kg)< unprocessed cassava peel meal (710.98 mg/kg). Live, slaughter and dressed weights, dressing percentage, meat to bone ratio, and pelt, shoulder, loin and leg expressed as the percentage of the dressed weight were lower (p<0.05) in ECPM than other diets. Other carcass parameters, meat organoleptic properties and savings on cost of feeding were not significantly influenced by the dietary treatments. Feed cost/kg body weight gain (BWG) decreased (p<0.05) with inclusion of 200 g/kg CPM in the diets. Differential cost/kg BWG and relative cost benefit/kg BWG showed similar trend and followed this rank order: RCPM &gt;SCPM &gt;ECPM (all p<0.05). Meat to bone ratio was positively and significantly (p<0.0001, R²= 0.9996) influenced by live, slaughter and dressed weights. The results indicate the efficacy of the processing methods in cassava peels detoxification, cost effectiveness of the 200 g kg-1 CPM diets and absence of negative effect of residual HCN contents of the detoxified CPM on the meat quality of the experimental rabbits.<hr/>Se realizó un estudio para determinar los efectos de la inclusión en la dieta de peladuras de yuca (CPM) sobre las características de la canal, calidad de la carne y economía de la producción de 32 conejos en crecimiento. Los conejos, de 6 semanas de edad y peso inicial de 567±23 g, fueron organizados en un diseño completamente al azar en un experimento de 9 semanas de duración. Se utilizaron cuatro dietas una dieta control (sin CPM) y otras con 200 g kg-1 de CPM ensilada (ECPM), secada al sol (SCPM) o enriada (RCPM) respectivamente. El contenido de ácido cianhídrico (HCN) de la CPM procesada fue: RCPM (98,10 mg/kg)< SCPM (165 mg/kg)< ECPM (299,21 mg/kg)< CPM sin procesar (710,98 mg/kg). Los pesos vivo, al sacrificio y de la canal, el rendimiento canal, carne/hueso, y los porcentajes sobre la canal de piel, lomo, espalda y pierna fueron menores (p<0,05) en la dieta ECPM. Otros parámetros de la canal, propiedades organolépticas, y ahorro en el coste de alimentación no fueron significativamente influidos por los tratamientos. El coste de alimentacion por kg de ganancia de peso vivo (BWG) disminuyó (p<0,05) con la inclusión de 200 g kg-1 de CPM en la dieta. El coste diferencial por kg de BWG y la relación coste/beneficio por kg BWG mostraron tendencias similares y mostraron la siguiente jerarquización: RCPM &gt;SCPM &gt;ECPM (todos p<0,05). La relacion carne/hueso fue positiva y significativamente (p<0,0001, R²= 0,9996) influida por los pesos vivo, al sacrificio y faenado. Los resultados muestran la eficacia de los métodos de procesamiento en la desintoxicación de las peladuras de yuca, la eficacia económica de la inclusión de 200 g kg-1 de CPM en las dietas y la ausencia de efectos negativos del HCN residual de la CPM desintoxicada sobre la calidad de la carne de los conejos experimentales. <![CDATA[<b>Genetic structure and bottleneck of the Guaymi bovine population by means of microsatellites</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300064&lng=en&nrm=iso&tlng=en Se caracterizó la población bovina Guaymí con un panel de 27 microsatélites seleccionados a partir de las recomendaciones hechas por la FAO/ISAG. Se analizaron muestras aleatorias de ADN obtenidas de la población bovina criolla Guaymí que se encuentran ubicadas en el área que comprende la comarca indígena Ngöbe-Buglé en la zona montañosa de la provincia de Chiriquí en la República de Panamá. Para cada microsatélite se calcularon el contenido de información polimórfica (PIC), el número medio de alelos (Na), la heterocigosis observada (Ho), la heterocigosis esperada (He), el estadístico F IS, y equilibrio Hardy-Weinberg (HWE). Además se calculó si existía cuello de botella en esta población. Los valores obtenidos fueron: PIC: 0,6899; Ne: 4,04; He: 0,7243; Ho: 0,7088; F IS: 0,0356. Se observaron tres microsatélites en desequilibrio (p<0,05). Los valores encontrados se consideran dentro de los rangos obtenidos en otras poblaciones criollas, exóticas y autóctonas españolas. Se requiere realizar estudios más detallados de estas poblaciones y su relación con otras poblaciones bovinas. No se observa cuello de botella en el pasado reciente de esta población.<hr/>Guaymi creole cattle were characterized by a 27 microsatellite panel, selected from a recommendation of FAO/ISAG. Random samples of DNA were taken from Guaymi creole cattle population in the highlands of the Chiriqui province in Ngöbe-Buglé region in the Panama Republic. From each microsatellite, was calculated the polymorphic information content (PIC), mean number of alleles (Na), observed heterozygosity (Ho), expected heterozygosity (He), the F IS statistic, the exact test for Hardy-Weinberg equilibrium (HWE). Besides a bottleneck study was calculated in this population. The result of the analysis show a PIC: 0.6899; Ne: 4.04; He: 0.7243; Ho: 0.7088; F IS: 0.0356. Three microsatellites were in unbalance (p<0.05). The Results are considered in the same range of values from other creoles, exotics and Spanish native populations. It requires more detailed studies of these populations and its relation to other cattle populations. No bottleneck was showed in the recent past. <![CDATA[<b>Performance <i>in vivo</i> and carcass characteristics of lambs fed with cashew apple bagasse</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300065&lng=en&nrm=iso&tlng=en Com o objetivo de avaliar o desempenho e as características da carcaça, foram utilizados 14 cordeiros desmamados inteiros, alimentados com dietas contendo ração comercial e silagem de sorgo ou bagaço de caju desidratado (BCD), como fonte única de volumoso. Os animais apresentaram peso corporal inicial médio de 12 kg e foram abatidos quando atingiram peso médio de 25 kg. Utilizou-se um delineamento inteiramente casualizado, com duas dietas e sete repetições. A conversão alimentar do grupo alimentado com BCD (8,08 ± 0,32) foi melhor (p<0,05) em relação ao grupo silagem de sorgo (15,62 ± 0,75). Não houve efeito significativo para as características do corpo in vivo e para as características qualitativas da carcaça dos cordeiros alimentados com os dois planos alimentares. Os cordeiros alimentados com BCD apresentaram um rendimento de carcaça fria superior (48,24 ± 0,73 vs. 44,05 ± 1,33; p<0,05) e uma maior deposição de gordura na região lombar. Conclui-se que o bagaço de caju desidratado é uma alternativa viável para a terminação de cordeiros mestiços, quando utilizado como fonte única de volumoso no nordeste.<hr/>In order to evaluate the performance and carcass characteristics were used 14 whole lambs, fed with diets containing concentrate and sorghum silage or dehydrated cashew apple bagasse (DCAP) as source of roughage. The animals had an average initial body weight of 12 kg and were slaughtered when they reached 25 kg of live weight. We used a completely randomized design with two diets and seven replicates. The feed conversion of the group fed with DCAP (8.08 ± 0.32) was better (p<0.05) compared to sorghum silage group (15.62 ± 0.75). There was no significant effect on the parameters of in vivo performance and on the quality characteristics of the carcass of lambs fed with the two feeding plans. The lambs fed with DCAP had a cold dressing percentage higher (48.24 ± 0.73 vs. 44.05 ± 1.33) and show a greater deposition of fat in the lumbar region. In conclusion, the dehydrated cashew apple bagasse is a viable source of feed for lambs fattening, in the northeast region of Brazil. <![CDATA[<b>Improving the quality of beef burger by adding thyme essential oil and jojoba oil</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300066&lng=en&nrm=iso&tlng=en Essential oils and their components are becoming increasingly popular as naturally occurring antimicrobial and antioxidant agents. Therefore, the present study aimed to investigate the effect of addition of different concentrations (0.02, 0.04, 0.06%) of essential oil of thyme (TEO) and 0.1% oil of jojoba (JO) on the quality and stability of beef burger. The obtained results indicated that the best sensory quality was attained at the highest TEO concentration (0.06%), while slight improvement in sensory quality was noticed in samples treated with JO (1%) as compared with control samples. The storage time significantly affected the TBA (thiobarbituric acid) values, as treated samples with TEO and JO showed lower values of TBA compared with the control samples. Regarding to microbial load, samples treated with 0.04 and 0.06% of TEO revealed significant reduction at 12th day of storage as compared with the control samples. On the other hand, the obtained results illustrated that JO have no significant effect on the microbial load.<hr/>Los aceites esenciales y sus componentes, son cada vez más populares como agentes antimicrobianos y antioxidantes existentes naturalmente. Por ello, el presente trabajo se centró sobre el efecto de la adición de diferentes concentraciones de aceite esencial (EO) de tomillo (0,02; 0,04; 0,06%) y aceite (O) de jojoba (0,1%) sobre la calidad y estabilidad de hamburguesas de ternera. Los resultados obtenidos indican que la mejor calidad sensorial fue conseguida con la mayor concentración de EO de tomillo (0,06%) mientras que solamente un débil aumento de la calidad sensorial fue registrado en las muestras tratadas con O de jojoba (1%) cuando se compararon con las muestras control. El tiempo de almacenamiento afectó significativamente a los valores de TBA (ácido tiobarbitúrico) mientras que las muestras tratadas con EO de tomillo y O de jojoba, mostraron valores más bajos que los controles. Con referencia a la carga microbiana las muestras tratadas con 0,04 y 0,06% de EO de tomillo, revelaron una reducción significativa con respecto al control en el día 12 de almacenamiento. Por otra parte, los resultados obtenidos ilustran que el O de jojoba no tiene efecto significativo sobre la carga microbiana. <![CDATA[<b>Estimative of repeatability coefficients, for leaf spot ocurrence in <i>Pennisetum</i> sp. clones</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300067&lng=en&nrm=iso&tlng=en O trabalho foi realizado na Estação Experimental de Itambé, do Instituto Agronômico de Pernambuco-IPA, e objetivou obter estimativas de parâmetros genéticos e de coeficientes de repetibilidade, sob diferentes métodos, da variável mancha ocular em clones de Pennisetum. Foram avaliados 16 clones de Pennisetum em delineamento de blocos ao acaso, com cinco repetições, no período de março de 2004 a maio de 2005, totalizando sete avaliações. Os coeficientes de repetibilidade foram estimados por: análise de variância, componentes principais - matriz de correlação, componentes principais - matriz de covariância e análise estrutural - matriz de correlação. O valor máximo da herdabilidade para mancha ocular foi de 95%. Os coeficientes de repetibilidade estimados pelos quatro métodos variaram de 0,75 a 0,78. As sete avaliações foram suficientes para obter coeficiente de determinação de 0,95 para todos os métodos avaliados. Não foi observada diferença entre os métodos avaliados.<hr/>The work was conducted at the Itambé Experimental Station, of the Pernambuco State Agricultural Research Enterprise, to obtain genetic parameters estimates and repeatability coefficient, under different methods, for leaf spot in Pennisetum clones. Sixteen Pennisetum clones were evaluated on a randomized block design, with five replicates, from March 2004 to May 2005, totaling seven evaluations. Repeatability coefficients were estimated by: analysis of variance, principal components - correlation matrix, principal components - covariance matrix, and structural analysis - correlation matrix. Maximum heritability for leaf spot was 95%. Repeatability coefficients the four methods ranged from 0.75 to 0.78 among. Seven evaluations were able to obtain determination a coefficient of 0.95 for all evaluated methods. No differences were observed among methods. <![CDATA[<b>Processing of diet for larvae of <i>Pimelodus britskii</i></b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300068&lng=en&nrm=iso&tlng=en Este trabalho objetivou avaliar a influencia do processamento de ração na dieta sobre o desenvolvimento de larvas de mandi-pintado (Pimelodus britskii). Foram utilizadas 75 larvas, distribuídas em um experimento inteiramente casualizado em 15 aquários de 5 l de volume útil em uma densidade de uma larva por litro. As rações foram processadas e fornecidas na forma farelada, pastosa e extrusada moída. As larvas foram alimentadas até a saciedade aparente por um período de 30 dias, 4 vezes ao dia: 8, 11, 14 e 17 h. Os parâmetros da água (oxigênio dissolvido, pH e condutividade) foram mensurados uma vez por semana. Não foram observadas diferenças no desempenho das larvas em relação ao peso médio final e sobrevivência. Para o comprimento médio final, a dieta extrusada moída foi melhor que a ração farelada (p<0,05), mas não diferiu da dieta pastosa. Os resultados indicam que o processamento da ração influencia no desempenho na fase inicial. Por tanto, recomenda-se a utilização de ração extrusada moída para se obter maior comprimento final dos animais.<hr/>This study aimed evaluate the influence of food processing in diet on development of larvae of Pimelodus britskii. Seventy five larvae were assigned in a completely randomized design to 15 aquariums of five liters at a density of one larva per liter. The diets were processed and supplied as mash, paste and extruded ground. The larvae were feeding to apparent satiation for a period of 30 days, four times daily: 8, 11, 14 and 17 h. The parameters of water (dissolved oxygen, pH and conductivity) were measured once a week. There were not differences in performance for final weight, and survival of larvae. For the average final length, the ground extruded diet was better than the mash diet (p<0.05) but not different from the pasty diet. These results indicate that processing of the feed influence the performance of the Pimelodus britskii in the initial phase. Therefore is recommended the use of ground extrused diets to achieve higher final length of animals. <![CDATA[<b>Varimax rotated principal component factor analysis of the zoometrical traits of Uda sheep</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300069&lng=en&nrm=iso&tlng=en A study was conducted to determine the interdependence among the conformation traits of 359 Uda rams using principal component factor analysis. The body measurements were withers height, body length, heart girth, rump height, rump width, rump length, face length, foreleg length and shoulder width. Age group of animals was a significant (p<0.05) source of variation for the studied traits. The various constituent parts of the body developed at varying rates. From the factor analysis, with varimax rotation of the transformation matrix, two principal components were extracted, which accounted for 86.3% of the total variance. The first principal component alone explained 80.8% of the variation, and tended to describe general size, while the second principal component had its loadings for meat traits (rump width, shoulder width and rump length). The two extracted principal components could be considered in selection programmes to obtain animals with better conformation using fewer measurements.<hr/>Se realizó un estudio para determinar la interdependencia entre los caracteres de conformación de 359 carneros Uda usando el analisis de componentes principales. Las medidas corporales fueron: alzada a la cruz, longitud corporal, perímetro torácico, alzada a la grupa, ancho y longitud de grupa, longitud de la cara, longitud de pata delantera y la anchura de la espalda. Los animales fueron agrupados por edades en: dientes de leche, 2 dientes, 4 dientes, 6 dientes, 8 dientes y dientes desgastados. El grupo de edad de los animales fue una fuente de variación significativa (p<0,05) de los caracteres estudiados. Las distintas partes componentes del cuerpo se desarrollaron a diferentes ritmos. Del analisis factorial a partir de la rotación varimax de la matriz de transformación, se extrajeron dos componentes principales que explicaron el 86,3 de la varianza total. El primer componente principal por si sólo explicó el 80,8% de la variación y tendió a describir el tamaño general, mientras que el segundo componente principal, responde por los caracteres relacionados con la carne (ancho de grupa y espalda y longitud de la grupa). Los dos componentes principales extraidos podrían ser considerados en los programas de selección, para obtener animales con mejor conformación usando pocas medidas. <![CDATA[<b>Polymorphisms of the 136 and 171 codons in the <i>PrP</i> gene in Uruguayan Creole sheep</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300070&lng=en&nrm=iso&tlng=en El scrapie es una enfermedad neurodegenerativa transmisible de ovinos y caprinos. Se caracteriza por la acumulación en el sistema nervioso central de una isoforma anómala de una proteína celular normal (PrPc) codificada por el gen PrP. En el exón 2 del gen se han identificado mutaciones en los codones 136, 154 y 171. La combinación de estos codones muestran diferentes niveles de asociación con la susceptibilidad a la enfermedad, desde muy resistentes (ARR/ ARR) a muy susceptibles (VRQ/VRQ). Los codones 171 y 136 son los mayores determinantes de la susceptibilidad al scrapie, mientras que el codón 154 juega un rol menor. En el presente trabajo se estudió una muestra de ovinos Criollos Uruguayos (N=28) para los codones 136 y 171. Las muestras de ADN genómico se procesaron por PCR-RFLP. Los resultados se obtuvieron por electroforesis en geles de poliacrilamida (10,5%) teñidos con AgNO3. Se analizaron las frecuencias genotípicas para los codones 136 y 171. Cinco genotipos diferentes fueron obtenidos, encontrándose en mayor frecuencia los genotipos de alta susceptibilidad: VQ/AQ= 0,39 y AQ/AQ= 0,29. El análisis de riesgo genético de esta majada según los genotipos obtenidos, reveló un 72% de animales muy susceptibles a la enfermedad en caso de manifestarse las condiciones ambientales propicias.<hr/>scrapie is a transmissible neurodegenerative disorder of sheeps and goats. It is characterized by the deposition in the central nervous system of an abnormal isoform of a normal cellular protein (PrPc), coded by the PrP gene. Mutations at 136, 154 and 171 codons of exon 2, are described. Combinations of these codons show different levels of association with the susceptibility to this disease; from highly resistants (ARR/ARR) to highly susceptibles (VRQ/VRQ). Codons 171 and 136 are the main determinant of scrapie susceptibility while codon 154 plays a minor role. In the present communication, a sample of Uruguayan Creole sheeps (N=28) was analysed for 136 and 171 codons. Samples of genomic DNA were processed by PCR-RFLP. The results were obtained by electrophoresis in polyacrylamide gel (10.5%) stained with AgNO3. Genotypic frequencies for the 136 and 171 codons were analysed. The results revealed 5 different genotypes. The most frequent genotypes were those associated with more susceptibility to the disease: VQ/AQ= 0.39 y AQ/AQ= 0.29. The analysis of genetic risk revealed a 72% of highly susceptible individuals, in case of proper environmental conditions. <![CDATA[<b>Supplementation with chromium yeast increase serum concentration of chromium in cattle</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300071&lng=en&nrm=iso&tlng=en O estudo avaliou o efeito da suplementação com doses crescentes de crômio/dia sobre a concentração sérica de Cr em bovinos. Sessenta novilhas da raça Nelore com idade entre 2 e 5 anos foram distribuídas aleatoriamente em 4 grupos (15 novilhas/grupo) alimentadas com pastagem de Brachiaria decumbens não fertilizada. No grupo controle (Gc), as novilhas receberam mistura mineral sem adição de Cr. Nos demais as novilhas receberam 0,59; 1,19 e 2,38 mg de Cr+3/animal/dia (grupos G8,5, G17 e G34, respectivamente). Colheramse amostras de sangue nos dias 0, 30 e 60. A concentração sérica de crômio foi determinada por meio de espectrofotometria de absorção atômica com forno de grafite. A fonte de crômio utilizada foi a levedura de crômio. Os resultados mostram que não houve diferença significativa (p&gt;0,05) na concentração sérica de crômio das novilhas entre os grupos G8,5, G17 e G34, num mesmo dia de observação. O único efeito observado foi do tempo de suplementação com crômio no o grupo G34. Neste grupo a concentração sérica de crômio apresentou aumento significativo (p<0,05) 60 dias após o início da suplementação. Conclui-se a levedura de Cr pode ser utilizada como fonte deste elemento mineral para os bovinos e a suplementação com 2,38 mg/bovino/dia foi a dose que mais elevou a concentração sérica de Cr nos bovinos da raça Nelore durante o período experimental.<hr/>This study evaluated the effect of daily chromium supplementation at growing doses on serum Cr levels in cattle. Sixty Nellore heifers 2 to 5 years old were randomly assigned to one of four groups (15 heifers/group) fed non-fertilized Brachiaria decumbens pasture. In the control group (Gc), the heifers received a mineral mixture without Cr. In the other groups, heifers received 0.59, 1.19 or 2.38 mg Cr+3/animal/day, groups G8,5, G17 and G34, respectively. Blood samples were collected on days 0, 30 and 60. Serum concentration of chromium was determined by graphite furnace atomic absorption spectrophotometer. The chromium source used was the chromium yeast. The results do not support any significant difference (p&gt;0.05) among serum chromium levels of heifers in groups Gc, G8,5, G17 and G34 at a same observation day. Only effect of supplementation time was detected in group G34. In this group there was significant increase (p<0,05) in the concentration serum chromium 60 days after the beginning of the experiment. Concluded Cr yeast can be used as the source of this mineral element for animals and supplementation with 2.38 mg/ cattle/day was the dose that most increased the serum concentration of Cr in Nellore cattle during the experimental period. <![CDATA[<b>Perception of producers facing the bovine traceability</b>: <b>Comparative study between Brazil and Chile</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300072&lng=en&nrm=iso&tlng=en O objetivo do presente trabalho foi analisar, de forma comparativa, a aplicabilidade e a percepção dos produtores de Dom Pedrito (Brasil) e Cunco e Vilcun (Chile) frente ao sistema de rastreabilidade bovina. O universo da pesquisa constituiu-se de dez produtores dos municípios de Cunco e Vilcun, e dez produtores do município de Dom Pedrito (Brasil). Constatou-se que os produtores pesquisados do Chile cumprem com grande parte das características operacionais de manejo, manutenção de registros e instalações do rebanho bovino, enquanto os produtores pesquisados no Brasil apresentam carências principalmente na manutenção de registros dos animais rastreados. Na percepção dos produtores pesquisados do Chile, a rastreabilidade influencia positivamente as características de manejo e gestão, ao contrário dos produtores pesquisados no Brasil que acreditam na influência mais intensa da rastreabilidade sobre as características de comercialização dos bovinos.<hr/>The objective of this study is to examine, in a comparative way, the applicability and the perception of the producers of Dom Pedrito (Brazil) and Cunco and Vicun (Chile) facing the cattle traceability system. The universe of the survey consisted of ten producers in the municipalities of Cunco and Vilcun, and ten producers in the municipality of Dom Pedrito (Brazil). It was found that producers surveyed in Chile to carry out most of the operational characteristics of management, maintenance of records and infrastructure of the cattle herd, while the producers surveyed of the Brazilian case presents lack mainly in the maintenance of records of animals. In Chilean perception, the traceability positively influences the characteristics of management and administration, unlike the case of Brazilian who producers surveyed believe in more intense influence of traceability on the characteristics of the market cattle. <![CDATA[<b>Estrus synchronization with PGF<sub>2</sub></b><b><sub>α</sub></b><b> and estrous behavior in Criollo Lechero Tropical cows</b>]]> http://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0004-05922011000300073&lng=en&nrm=iso&tlng=en En 36 vacas Criollo Lechero Tropical (CLT) cíclicas y lactantes se sincronizó el estro con PGF2α y se determinó la tasa de manifestación del estro (ME), el inicio (IE), final y duración (DE) del estro; se registró además la conducta sexual y el tiempo de pastoreo, rumia, descanso y sueño de las vacas en el proestro, estro y metaestro. La tasa de ME fue 67%, el IE después de la PGF2α sucedió a las 80,5±10,3 h y la DE fue 16,2±1 h. Durante el estro las vacas recibieron 67±13 montas y efectuaron 62,3±22; se observaron 27,9±19,6 topeteos, 21,4±4 olfateos de genitales y 1,7±0,4 Flehmen, y las vacas dedicaron 3,2±2,1 h a seguir a otras hembras, 2±1,3 h a pastorear, 1,7±0,8 h a rumiar, 1,5±0,3 h a descansar y 0,2±0,1 h a dormir. En conclusión, la PGF2α produjo aceptable tasa de ME y conducta sexual intensa en vacas CLT, y el tiempo dedicado a alimentación y descanso disminuyó durante el estro. Es necesario estudiar el ciclo estrual natural para determinar con precisión la conducta de vacas CLT durante el estro.<hr/>In 36 cyclic and lactating Criollo Lechero Tropical (CLT) cows estrus was synchronized with PGF2α and the estrus manifestation (ME) rate, the onset (IE), end and duration (DE) of estrus were determined; in addition, the sexual behavior of the cows and the time spent grazing, ruminating, resting and sleeping in the proestrus, estrus and metestrus were recorded. The ME rate was 67%, the time of IE after PGF2α was at 80.5±10.3 h and the DE was 16.2±1 h. During estrus cows received 67±13 mounts and gave 62.3±22, 27.9±19.6 buttings, 21.4±4 genitalia sniffing and 1.7±0.4 Flehmen were observed, and cows spent 3.2±2.1 h following other herdmates, 2±1.3 h grazing, 1.7±0.8 h ruminating, 1.5±0.3 h resting and 0.2±0.1 h sleeping. In conclusion, PGF2α produced acceptable ME rate and intense sexual behavior in CLT cows, while time spent feeding and resting decreased during estrus. It is necessary to study the natural estrous cycle to accurately determine the behavior of CLT cows during estrus.