Archivos de Zootecnia

Phytase levels in rations for finishing pigs

O objetivo do experimento foi avaliar os efeitos da inclusão de diferentes níveis de fitase em rações com elevada concentração de ácido fítico, para suínos em fase de terminação sobre o desempenho, características de carcaça e a qualidade de carne. Os tratamentos experimentais foram: ração sem fitase, e rações com 500, 1000 e 1500 UFA (unidades de fitase). As rações foram formuladas com a base de farelo de gérmen de milho desengordurado, farelo de soja e milho grão, sendo isonutrientes e fornecidas ad libitum durante 28 dias pré-abate. Foram avaliadas as características de desempenho, carcaça, qualidade da carne, oxidação lipídica, os níveis séricos de ferro, cálcio e fósforo, e a concentração fecal de cálcio e fósforo. Foram utilizados 32 suínos (Landrace x Large Withe), 16 machos castrados e 16 fêmeas, com peso médio inicial de 60,3±5,32 kg, alojados individualmente. O delineamento experimental foi em blocos casualizados, em um modelo fatorial 4 x 2 (4 níveis de fitase e 2 sexos ), onde a unidade experimental foi o animal. Houve melhora (p<0,05) na conversão alimentar para os tratamentos com 1000 e 1500 UFA de fitase e menor consumo de ração (p<0,05) para o grupo tratado com 1500 UFA de fitase em relação ao grupo controle (sem fitase). Para a perda de água no descongelamento o tratamento com 1500 UFA de fitase apresentou piora (p<0,05) no índice em relação ao grupo controle. Foi verificado efeito quadrático (p<0,05) para a quantidade de fósforo nas fezes, sendo o ponto de mínima de 998,24 UFA, e menores concentrações (p<0,05) para os tratamentos com fitase (500, 1000 e 1500 UFA) em relação ao grupo controle. A adição de fitase sob o nível de 1000 UFA é positiva na redução da eliminação do fósforo fecal e na melhora da conversão alimentar, sem efeitos deletérios na qualidade da carne.

This experiment was conducted with the aim of evaluate the inclusion of different levels of phytase in the rations with high phytic acid concentration to finishing pigs on performance, carcass characteristics, and meat quality. The experimental treatments were: ration without phytase, and rations with phytase (500, 1000 and 1500 PPU). The rations were isonutritive, based on corn grain, soybean meal, and defatted corn germen meal ingredients and were offered ad libitum during 28 days before the slaughter. Were evaluated the pig performance, carcass characteristic, meat quality, lipidic oxidation and serum profile of iron, calcium an phosphorus and fecal profile of calcium and phosphorus. Thirty two pigs (Landrace X Large Withe), 16 male and 16 female, with 60.3±5.32 kg of initial weight, were allocated on individual pens. The experimental design was randomized blocks, using a 4 x 2 factorial model (4 levels of phytase and 2 sexes), been each animal considered a replicate. There was a better (p<0.05) feed conversion rate in groups receiving 1000 and 1500 PPU of phytase and a lower consumption of ration (p<0.05) in the group treated with 1500 PPU of phytase than the control group. It was observed a quadratic effect (p<0.05) for phosphorus levels in feces, where the best point was 998.24 PPU, and there were lower concentrations (p<0.05) of phosphorus in the feces of treated groups (500, 1000 and 1500 PPU) compared to the control group. The addition of phytase at the level of 1000 PPU is positive to reduce the phosphorus elimination and improve the feed conversion rate, without deleterious effects on meat quality.

Estimation of genetic parameters for milk yield in lactations of Mambí Cuban cows

Se utilizaron 25 036 registros de producción de leche acumulada hasta 305 días (13 495 de primera lactancia (L1), 6067 de la segunda (L2), 3445 de la tercera (L3) y 2029 de la cuarta (L4), respectivamente) pertenecientes a 13 495 vacas Mambí de Cuba (¾ Holstein ¼ Cebú) que parieron entre los años 1981-2006, distribuidas en 173 rebaños de 4 empresas ganaderas. El objetivo de este estudio fue estimar las heredabilidades y correlaciones genéticas entre las cuatro primeras lactancias (L1-L4) y determinar si la primera lactancia podría ser considerada como criterio de selección de vacas y sementales de esta raza. Para estimar los componentes de (co) varianza y parámetros genéticos se utilizó el programa REMLF90 empleando un modelo animal multivariado que incluyó como efecto fijo el grupo de contemporáneos (rebaño-año-cuatrimestre de parto), la edad al parto como covariable lineal y cuadrática, y como efectos aleatorios el animal y el error. Los promedios para L1 hasta L4 fueron de: 1957 kg, 2086 kg, 2099 kg y 2106 kg, y los valores de heredabilidad fueron 0,22 ± 0,03; 0,17 ± 0,04; 0,22 ± 0,05 y 0,26 ± 0,06, respectivamente. Las correlaciones genéticas entre las cuatro primeras lactancias fueron altas con valores entre 0,76 y 0,95. Se concluye que es posible obtener ganancias genéticas mediante selección por producción de leche; que hubo un alto porcentaje de genes en común que influyeron en las diferentes lactancias, y que la producción lechera en la primera lactancia es un buen indicador del comportamiento productivo de las vacas Mambí de Cuba, que puede ser utilizada como criterio de selección.

The records of 25 036 lactations of milk yield up to 305 days (13 495 in first lactation (L1), 6067 in the second (L2), 3445 in the third (L3) and 2029 in the fourth (L4), respectively) from 13 495 Cuban Mambí (¾ Holstein ¼ Cebú) cows were used. The cows calved between 1981 and 2006 in 173 herds of four genetic farms. The goal of this study was to estimate the heritability and genetic correlations the first four lactations (L1-L4) and determine if the first lactation could be considered as selection criteria for cows and sires of the breed. The REMLF90 program was used for estimating the (co) variance components and the genetic parameters by means of a multivariate animal model that included the contemporary group (herd-yearcalving season) as fixed effect, calving age as linear and quadratic covariable, and the animal and the error as random effects. The means for L1 up to L4 were of 1957 kg, 2086 kg, 2099 kg and 2106 kg, and the heritability values were of 0.22 ± 0.03, 0.17 ± 0.04, 0.22 ± 0.05 and 0.26 ± 0.06, respectively. The genetic correlations between the first four lactations were high, with values between 0.76 and 0.95. It was concluded that it is possible to obtain genetic gain through milk yield selection, that a common group of genes are affecting the different lactations, and that milk yield in the first lactation is a good indicator for productive performance of Cuban Mambí cows, that can be used as selection criteria.

Diurnal intake behavior of Girolanda cows at different stocking rates

Objetivou-se verificar o comportamento de vacas em diferentes taxas de lotação (2, 4 e 6 UA), em pastejo rotacionado. O delineamento experimental utilizado foi blocos ao acaso em arranjo de parcelas subdivididas com medidas repetidas no tempo, com três repetições. As observações do comportamento ingestivo dos animais foram realizadas de 10 em 10 minutos durante o período diurno. O tempo de pastejo, ruminação, ócio e de outras atividades dos animais foi afetado pelo período de avaliação, dia de pastejo e taxa de lotação. Verificou-se a presença de correlação negativa entre o tempo de pastejo e tempo de ruminação, de ócio, outras atividades, índice de temperatura e umidade (ITU) e índice de temperatura globo e umidade (ITGU). Durante os períodos em que ocorreu precipitação pluviométrica os animais apresentaram comportamento de pastejo semelhante (tempo de pastejo médio de 434 minutos), o que permitiu o uso de ambas as lotações, sem maiores danos ao comportamento dos animais, no período chuvoso do ano.

The behavior of cows at different stocking rates (2, 4 and 6 UA), in rotational grazing was studied. The experimental design was randomized blocks in an split plot arrangement with repeated measures and three repetitions. Observations of feeding behavior of the animals were held every 10 minutes during the daytime. Grazing, rumination, and other activities of the animals were affected by period of grazing, days of grazing and stocking rate. There were negative correlations between grazing time of animals and the variables: rumination time, leisure, other activities, temperature and humidity index (ITU) and black globe-humidity index (ITGU). During periods when rainfall occurred the animals showed similar behavior of grazing (grazing time average of 434 minutes), which allowed the use of both stocking rates, without much damage to the behavior of the animals in the rainy season.

Bayesian analysis for the index scrotal circumference/weight on Nellore animals born in the Tocantins State, Brazil

Objetivou-se com este trabalho estimar os parâmetros genéticos do índice perímetro escrotal/ peso padronizado para 365 dias de idade (IND365), via inferência bayesiana, sob dois modelos de análise distintos, em animais da raça Nelore criados no Estado do Tocantins, Brasil. O arquivo final estava constituído de 693 registros do IND365 distribuídos em 16 grupos de contemporâneos. Os componentes de variância foram analisados via inferência bayesiana, por meio de programas em linguagem Fortran. Amostragem a cada 100 ou 500 rodadas e um burn-in pouco conservador poderão ser implementados. As médias pontuais para os coeficientes de herdabilidade direta e materna para o IND365 foram respectivamente: 0,18 (com ou sem efeito materno) e 0,14. Estes resultados sugerem que o IND365 possa ser utilizado como critério alternativo nos programas de melhoramento e responder de forma satisfatória ao processo de seleção.

The aim of this study was to estimate the genetic parameters of the index scrotal circumference/weight standarized for 365 days of age (IND365), via bayesian inference, in two separate models of analysis on Nellore animals born in the Tocantins state, Brazil. The file was composed of 693 records of the IND365 divided into 16 contemporaneous group. Variance components were analyzed via bayesian inference, through the programs in Fortran language. Sampling of every 100 or 500 rounds and a little conservative burn-in can be implemented. Means of direct heritabilities were 0.18 (with and without maternal effect) and 0.14 for maternal heritabilities. These results suggest that the IND365 can be used as alternative criterion in breeding programs to Nellore cattle and respond satisfactorily to the selection process.

Margins and comercialization channels of añejo cheese in Zacazonapan, Mexico

Para analizar los canales y márgenes de comercialización del queso añejo, en 2007 se realizó una investigación en el municipio de Zacazonapan, México, en la cual se identificó el canal de comercialización más utilizado en este tipo de queso por los productores, y se estimaron los márgenes absoluto y relativo, a través de los valores equivalentes, costos y ganancias de cada agente participante. El 83,3% de los queseros ocupó el primer eslabón de la cadena producción-consumo y los intermediarios el 16,7%. Los primeros participaron en 100% del precio que pagó el consumidor final y los segundos con 33,4%. El margen bruto de comercialización del queso añejo en su modalidad madurado (8 días de maduración) fue 5,59 US$/kg; que en términos relativos significa que el quesero se apropió 58,29% del precio final que pagó el consumidor y los intermediarios 45,16%. Respecto al valor del queso madurado, el quesero se apropió de 41,71% y el resto los intermediarios. El canal de comercialización más común fue productor (quesero)-consumidor final.

In order to analyze margins and commercialization channels of añejo cheese, during 2007 a research was carried out in Zacazonapan, Mexico. The commercialization channel more used by producers in this kind of cheese was identified, and relative and absolute margins were obtained using equivalent values, revenues, and cost of each agent. Results indicates that 83.3% of cheese makers obtained the first step of consumptionproduction chain and 16.7% was occupied by brokers, in the same way, first of them get 100% of price that final consumer paid and the seconds 33.4%. The gross total commercialization margin of añejo cheese in its modalities mature (8 days of mature) was 5.59 US$/kg; in relative words it means that the cheese producer give him 58.29% of final price that the consumer paid and the brokers 45.16%. Respect to the same value of cheese mature, the cheese producer give him 41.71% and the difference was obtained by brokers. Commercialization channel most common was producer-final consumer.

Ingestive behavior of ewes submitted or not to nutritional restriction during pregnancy

Foi avaliada a influência da gestação, do número de fetos e da restrição nutricional no comportamento ingestivo de 24 ovelhas Santa Inês avaliadas aos 90, 110 e 130 dias de gestação, divididas entre os tratamentos em função do número de fetos. Essas receberam dietas à vontade ou restritas, sendo essa com redução de 15% nos requisitos de proteína e energia. As ovelhas foram observadas individualmente, a cada 5 minutos, por 3 dias, sendo dois períodos de 24 h intercalado com 24 h de descanso. Durante as observações foram determinando os tempos gastos com ingestão, ruminação, ócio e mastigação. O manejo nutricional não influenciou o tempo gasto com a ingestão. Em ambas as categorias de prenhez, aos 90 dias de gestação, as ovelhas despenderam menos tempo para ingestão do alimento. Animais recebendo dieta restrita ruminaram mais tempo e aos 90 dias de gestação despenderam menos tempo ruminando. Ovelhas gestantes de dois fetos gastaram menos tempo mastigando do que as de gestação simples. O avanço da gestação aumentou o tempo despendido com ingestão, ruminação e mastigação. A restrição nutricional aumentou o tempo em ócio de ovelhas com um feto. Animais gestantes de um e dois fetos apresentaram comportamento ingestivo variável nas fases da gestação estudadas.

This research was carried out in order to evaluate effects of pregnancy, fetus number and nutritional restriction on ingestive behavior of ewes. Were used 24 ewes of the breed Santa Ines evaluated at 90, 110 and 130 pregnancy days distributed among treatments according to fetus number. They received free or restricted diet, the last one with reduction of 15% of protein and energy requirements. Ewes were individually observed each five minutes for three days, being two periods of 24 h intercalated with 24 h of resting. During the observations was determinated the time spent in feeding, rumination, idle and chewing. Feed management did not influence time spent in feeding. In both pregnancy categories, at 90 days of pregnancy the animals spent less time in rumination and feeding. Ewes on nutritional restriction ruminate longer time and at 90 days of pregnancy spent less time ruminating. Ewes with twin fetus spent less time chewing than with single pregnancy. Pregnancy progress increased time spent to feeding, rumination ant chewing. Nutritional restriction increased idle time in ewes with one fetus. Ewes with single and twin pregnancy showed variable ingestive behavior at the studied phases.

Intake, digestibility and blood parameters of lambs fed diets with palm kernel

Este trabalho foi realizado com o objetivo de verificar o melhor nível de inclusão da torta de dendê por intermédio do consumo e da digestibilidade dos nutrientes e parâmetros sanguíneos em cordeiros terminados em confinamento. Utilizaram-se 20 animais inteiros, Santa Inês, alimentados com farelo de milho, farelo de soja, feno de tifton 85 e níveis de torta de dendê (0,0; 6,5;13,5 e 19,5% da matéria seca), em mistura completa. O período experimental teve duração de 24 dias. Durante três dias consecutivos, foram coletadas amostras do alimento, das sobras e fezes para determinação do consumo e da digestibilidade. No último dia, foram coletadas amostras de sangue para analise do N-uréico e glicose plasmático. Os consumos de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB) e nutrientes digestíveis totais (NDT), expressos em grama por dia (g/dia), porcentagem peso corporal (%PC) e grama por quilo peso metabólico (g/kgPM), não foram influenciados pela inclusão da torta de dendê, enquanto os de fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e extrato etéreo (EE) tiveram efeito linear crescente e os de carboidratos não fibrosos (CNF), decrescente, com a adição da torta. A inclusão da torta na alimentação proporcionou efeito linear decrescente para os coeficientes de digestibilidade de CNF. Não houve efeito de tratamento sobre os níveis de N-uréico e glicose sanguíneos, no entanto, foi observado efeito quadrático decrescente no período pós-prandial. Pode-se incluir até 19,5% da torta de dendê na dieta dos cordeiros, sem efeitos nas variáveis estudadas.

This study was conducted in order to verify the best level of palm kernel for sheep diet by intake, nutrient digestibility and blood parameters in terminated feedlot lambs. Twenty non-castrated Santa Inês lambs were fed diets with corn meal, soybean meal, Tifton 85 hay and palm kernel levels (0.0; 6.5; 13.00 and 19.5% in dry matter), as total mixed ration. The experiment lasted 24 days. For three consecutive days, feed, orts and faeces were sampled for determination of intake and nutrient digestibility. At the last day, blood was collected for plasma urea nitrogen and glucose. Dry matter (DM), organic matter (OM), crude protein (CP) and total digestive nutrients (TDN) expressed by g/day, body weight percentage (%BW) and grams per kg of metabolic weight (g/kg MW) intake were not influenced by palm kernel inclusion, while neutral detergent fiber (NDF), acid detergent fiber (ADF) and ether extract (EE) increased with palm kernel levels and non-fibrous carbohydrate decreased. Digestibility coefficient of noncarbohydrate decreased as levels of palm kernel increased. Blood urea nitrogen and glucose levels were not influenced by the diets, however, diets promoted quadratic effect at post feeding. Up to 19.5% of palm kernel can be included in diets for lambs, with no effects on studied variables.

Glutamine and nucleotide supplementation in broiler diets in alternative breeding system

Objetivou-se avaliar o efeito da suplementação com glutamina e nucleotídeos na dieta sobre o desempenho e morfologia da mucosa intestinal de frangos de corte criados no sistema alternativo. Foram utilizados 600 pintos de corte machos distribuídos em delineamento em blocos casualizados, no esquema fatorial 3x2 (três níveis de glutamina: 0,0; 0,5 e 1,0% e dois níveis de nucleotídeos purificados na dieta: 0,0 e 0,04%), totalizando 6 tratamentos, com 4 repetições de 25 aves cada. Foram obtidos os dados de desempenho (peso corporal, ganho de peso, consumo de ração, conversão alimentar e mortalidade) aos 7, 21 e 42 dias de idade. Ao final do experimento foram abatidas 4 aves/tratamento para avaliação do peso de órgãos e da morfologia intestinal. A adição de 1% na dieta melhorou o ganho de peso, consumo de raçao e conversão alimentar na primeira semana de idade. Não sendo encontrados resultados positivos nos períodos de 21 e 42 dias de idade. A suplementação de glutamina e nucleotídeos em dietas de frangos de corte criados no sistema alternativo não influencia o desempenho e a morfologia intestinal, a inclusão de 1,0% de glutamina no período de 1 a 21 dias de idade, favorece o desempenho das aves.

The experiment was conducted to evaluate the effect of supplementing glutamine and nucleotides on growth performance and development intestinal morphology in broiler chicks. In the trial, 600 male broiler chicks distributed in randomized blocks in a 3x2 factorial arrangement (consisting of a uniform basal diet supplemented with: 0.0, 0.5 or 1.0% glutamine, and 0.0 or 0.04% nucleotides), for a total of 6 treatments with 25 birds each. Means of performance (weight, weight gain, feed intake, feed conversion and mortality) were obtained 7, 21 and 42 days of age. At the end of the experiment 4 broilers per treatment were used to determine organs weight and development intestinal morphology. Glutamine supplementation (1%) improved the body weight, feed intake and feed conversion in the first week. Glutamine and nucleotides supplementation did not affect performance in broiler chicks in the period one to 21 and one to 42 days of age. In conclusion, it was demonstrated that feeding 1.0% glutamine improved growth performance of broiler birds at 21 days of age.

Validation of mathematical models for prediction of voluntary consumption and weight gain of beef cattle

Avaliou-se a utilização das equações do Cornell Net Carbohydrate and Protein System (CNCPS) e Nacional Research Council (NRC) nível 1 para predição de consumo de matéria seca e ganho em peso médio diário em condições tropicais de confinamento. Utilizou-se 23 bovinos mestiços Holandês/Zebu confinados em baias individuais com idade média de 20 meses e 260 kg de peso vivo no início do experimento. As dietas experimentais eram isonitrogenadas compostas por dois níveis de ingestão de energia com 50 ou 80% de inclusão de concentrado na base da matéria seca para os tratamentos médio (TM) e alto (TA), respectivamente. Observou-se respostas variáveis dos valores observados e preditos de consumo de matéria seca e ganho em peso em função dos níveis alimentares sendo que as melhores predições de consumo foram para o tratamento de médio nível de concentrado em que as equações de regressão apresentaram R²= 0,61 e 0,63 para o CNCPS e NRC, respectivamente. Os modelos foram ineficientes para predição do consumo de matéria seca no tratamento de alta inclusão de concentrado e não apresentaram predição acurada de ganho em peso médio diário em nenhuma das condições experimentais analisadas.

We evaluated the use of equations of the Cornell Net Carbohydrate and Protein System (CNCPS) and National Research Council (NRC) level 1 to predict the dry matter intake and daily weight gain in tropical conditions of feedlot. We used 23 crossbred steers Holstein / Zebu kept in individual stalls with a mean age of 20 months and 260 kg live weight at the start of the experiment. The experimental diets were isonitrogenous composed of two levels of energy intake with 50 or 80% of concentrate in dry matter basis for treatments medium (TM) and high (TA), respectively. Observed variable responses between the observed and predicted values for dry matter intake and weight gain depending on level of concentrate. The best estimate of dry matter intake occurred for the treatment of middle level of concentrate on which the regression equations presented R²= 0.61 and 0.63 for the CNCPS and NRC, respectively. The models were inefficient for predicting dry matter intake in the treatment of high concentrate inclusion and did not present accurate prediction of daily weight gain in any experimental conditions analyzed.

Nutritional value and structural characteristics of tropical grasses under nitrogen fertilization

O experimento foi conduzido na Fazenda Experimental da Unioeste, Marechal Cândido Rondon, PR, Brasil, com o objetivo de avaliar os efeitos de doses crescentes de N sobre características estruturais e composição química de três gramíneas forrageiras tropicais. O delineamento experimental utilizado foi o em blocos casualizados em esquema fatorial 3 x 4, com três forrageiras tropicais (Panicum maximum cvs. tanzânia e mombaça, e Brachiaria sp. cv. mulato) e quatro doses de N (0; 40; 80 e 160 kg/ha) tendo como fonte a uréia. Foram avaliados: a altura do dossel, a relação folha/colmo, a proporção de folhas e de colmos na forragem produzida, o diâmetro e a altura do pseudocolmo, e os teores de proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e matéria mineral (MM). Houve efeito das doses de N sobre a altura do dossel e sobre a altura do pseudocolmo, que apresentaram comportamento quadrático. A relação folha/colmo respondeu de forma negativa às doses de N, enquanto o diâmetro do pseudocolmo foi influenciado apenas pelas forrageiras. Para o teor de PB foi constatada significância da interação dos fatores, de forma que na dose de 80 kg/ha de N o capim tanzânia foi superior aos demais. Os teores de FDN responderam de forma quadrática às doses de N, enquanto os teores de FDA foram influenciados apenas pelas forrageiras.

The experiment was carried out in the experimental farm of Unioeste, Marechal Candido Rondon, PR, Brasil, with the objective of evaluate the effects of increasing N doses under structural features and chemical composition of three tropical forage grasses. The experimental design used was of randomized blocks in factorial scheme 3x4, with three tropical forages (Panicum maximum cvs. tanzânia and mombaça, and Brachiaria sp. cv. mulato) and four doses of N (0; 40; 80 and 160 kg/ha) taking urea as N sources. Were evaluated: canopy height leaf/stem ratio, diameter and height of pseudoculm, and contents of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and mineral matter (MM). There was effect of N doses on canopy height and height of pseudoculm that showed quadratic behavior. The leaf/stem ratio responded negatively to N doses, while the diameter of pseudoculm was influenced only by forages. For CP content was found significance of interaction of factors, being that in dose of 80 kg/ha of N the Tanzania grass was higher than the other. The contents of NDF responded of form quadratic to N doses, while the contents of ADF were influenced only by forages.

Determination of methane production in goats fed different cereal diets

Se utilizaron tres cabras primíparas de raza Murciano-Granadina de un año y medio de edad y en estado de mantenimiento, con un peso medio de 33,08 ± 2,1 kg, con el objeto de determinar la producción de metano al administrarles dos dietas que difirieron únicamente en el tipo de cereal (grano de cebada o maíz). Se realizaron dos pruebas de digestibilidad consecutivas mediante la administración de las dos dietas. Tras un periodo de adaptación de 7 días se analizó la digestibilidad aparente durante 5 días. La producción de metano (CH4) se determinó por calorimetría indirecta mediante una máscara de circuito abierto adaptada a pequeños rumiantes. El CH4 se midió el día 4 de la prueba de digestibilidad, antes de administrar la ración diaria y se realizaron tres medidas más cada 35 minutos mientras comían. No se observaron diferencias significativas en el consumo de materia seca (con 758 g MS/cabra y día de media), ni entre los coeficientes de digestibilidad de materia seca de las dos dietas (CDMS= 69,2% de media). Durante la comida se observaron diferencias (p<0,05) en la producción de metano con valores de 0,69 l/h para la dieta que contenía grano de cebada frente a 0,77 l/h para la dieta con grano de maíz. Cuando se expresó la producción de CH4 sobre la ingestión de energía (Ym) no se observaron diferencias significativas entre dietas, y el valor medio para las dietas mixtas estudiadas fue de 4,8.

Three primiparous 1.5 year old Murciano-Granadina female goats in maintenance were used. Their average body weight was 33.08 ± 2.1 kg. The objective was to determine methane production in two diets differing of the type of cereal grain (barley or corn). Two consecutive digestibility trials were conducted using diets differing in the cereal type (barley or maize grains). The adaptation period has a duration of 7 days and the digestibility period 5 days. Methane production (CH4) was determined by indirect calorimetry with an open circuit mask adapted to small ruminants. Methane production was determined on day four of digestibility trial, before feeding and three more measurements every 35 minutes during feeding. There were no significant differences neither in dry matter intake (758 g MS/goat and day on average) nor in dry matter digestibility coefficients (CDMS= 69.2% on average). Significant differences (p<0.05) were observed in the methane production during the feeding time with levels of 0.69 and 0.77 l/h for the barley and maize based diets, respectively. No significant differences between diets were observed when CH4 was expressed on gross energy intake basis, and the value obtained for the experimental mixed diets was 4.8.

Combining abilities of growth traits among pure and crossbred meat type chickens

Five thousand one hundred and nineteen chicks were obtained from a diallel combination of four breeds of chickens; (Anak Titan (A), Alpha (B), Giriraja (G) and Normal indigenous (N) chickens) in a broiler improvement program. The chicks were reared to 12 weeks in which data on weekly body weight (BW), breast girth (BG) and tibia length (TL) were recorded. Sire and dam genotype significantly (p<0.05) affected all traits. Anak Titan cocks and hens performed best in body weight (BW) with values ranging from 38.45 ± 0.74 g and 40.21 ± 0.66 g at day old to 1135.93 ± 35.67 g and 953.38 ± 35.38 g at week 12 respectively. Normal and Alpha improved indigenous performed better in linear body parameters. Results of diallel analysis to test for general and specific combining abilities of breeds on traits showed that additive genetic effects were important in determining BW and dominance effects were important for BG, while both effects were important in determining TL. This indicates that selection, crossbreeding and combination of both are tools needed to improve BW, BG and TL, respectively. Anak Titan had the best general combining ability (GCA) of 19.49 ± 0.42, 288.54 ± 7.52, 458.78 ± 12.15 and 769.30 ± 4.80 for BW at weeks 1, 4, 8 and 12, respectively and therefore recommended as a good breed for BW in the improvement program. GB crosses had the best SCA for BG and TL of 7.43 ± 0.11, 8.21 ± 0.16, 11.82 ± 0.22, 5.90 ± 0.29; 8.50 ± 0.10, 9.68 ± 0.10, 7.92 ± 0.34, 0.86 ± 0.30 at weeks 1, 4, 8 and 12 respectively. It is recommended that an improvement process that involves all the breeds should be adapted using reciprocal recurrent selection or modifications of it.

Cinco mil ciento diecinueve pollos fueron obtenidos, en un programa de mejora de pollos de engorde, a partir de una combinación dialélica de cuatro razas: Anak Titan (A), Alpha (B), Giriraja (G) y Normal indígena (N). Los pollos fueron criados a 12 semanas en las que se registraron los datos sobre peso corporal por semana (BW), circunferencia del pecho (BG) y longitud de la tibia (TL). El genotipo de machos y hembras afectó significativamente (p<0,05) a todos los caracteres. Los gallos y las gallinas Anak Titan mostraron el mejor comportamiento en peso corporal (BW) con valores que van desde 38,45 ± 0,74 g a 40,21 ± 0,66 g al día de edad hasta 1135,93 ± 35,67 g y 953,38 ± 35,38 g en la semana 12, respectivamente. Las razas indígenas mejoradas Normal y Alpha obtuvieron mejores resultados en los parámetros lineales del cuerpo. Los resultados del análisis dialélico para probar las capacidad general y específica de combinación de las razas en los caracteres, mostraron que los efectos genéticos aditivos fueron importantes en la determinación BW y los efectos de dominancia fueron importantes para BG, mientras que ambos efectos son importantes en la determinación de TL. Esto indica que la selección, el mestizaje y la combinación de ambos son las herramientas necesarias para mejorar la PN, BG y TL, respectivamente. Anak y Titan han mostrado la mejor aptitud combinatoria general (GCA) de 19,49 ± 0,42; 7,52 ± 288,54; 458,78 ± 12,15 y 769,30 ± 4,80 para BW en las semanas 1, 4, 8 y 12, respectivamente, por lo que se recomienda como una buena raza para el programa de mejora de BW. Los cruces GB presentaron la mejor SCA para BG y TL de 7,43 ± 0,11; 8,21 ± 0,16; 11,82 ± 0,22; 5,90 ± 0,29; 8,50 ± 0,10; 9,68 ± 0,10; 7,92 ± 0,34 y 0,86 ± 0,30 en las semanas 1, 4, 8 y 12, respectivamente. Se recomienda que un proceso de mejora continua que involucre a todas las razas debe adoptarse mediante selección recurrente recíproca o modificaciones del ella.

Evaluation of the primary productivity of temperate grassland in Santa Fe, Argentina

El objetivo del trabajo fue generar modelos simples de producción total y estacional de fitomasa aérea de un pastizal templado ubicado en un ambiente de media loma baja. Se utilizaron como predictores precipitaciones, temperaturas medias y relación porcentual entre especies forrajeras, de medición sencilla. El análisis se basó en una serie de ocho años (2002-2009) de datos de producción estacional acumulada de un pastizal ubicado en la localidad de Bustinza, Santa Fe, Argentina. Cada año se estimó la fitomasa aérea por corte manual de 10 muestras de 0,25 m². El material obtenido se separaró en gramíneas C3 y C4, anuales y perennes, graminoides y dicotiledóneas y se calculó la composición florística, en base de materia seca. La producción promedio fue de 9051 kg/ha. Se obtuvieron modelos de regresión satisfactorios entre las precipitaciones anuales y la producción primaria aérea neta; y entre la producción estacional, las precipitaciones estacionales y la relación porcentual entre grupos de especies. Las ecuaciones ajustadas para predecir la producción estacional del pastizal son simples y podrían ser utilizadas en regiones con pastizales de similar estructura.

The objective this work was to generate simple models of total and seasonal production for shoot biomass in temperate grassland located in a medium low ridge. Were used as predictors simple measurable parameters (rainfall, average temperatures and percentage relationship between forage species). The analysis was based on a series of eight years (2002-2009) of seasonal production data accumulated in a pasture located in Bustinza, Santa Fe, Argentina. In each year the productivity was estimated by manual cutting of 10 samples of 0.25 m². This material was separated in C3 and C4 grasses, annuals and perennials, graminoids and perennial dicots and estimated the proportion of each fraction in the base of dry matter. The average production was 9051 kg/ha. The obtained regression models between annual rainfall and net aerial primary production and between production of seasonal rainfall at each station and the percentage ratio between groups of species were satisfactory. The equations to predict the seasonal production of pasture were good and simple estimators, and could be used in other regions having similar grassland structure.

Milk net energy and performance of calves from Aberdeen Angus primiparous cows

O estudo teve como objetivo avaliar a disponibilidade de energia líquida no leite de vacas primíparas Aberdeen Angus e sua relação com o desempenho ponderal dos bezerros. Foram utilizadas 47 vacas, criadas em condições extensivas, no município de Aceguá, RS, no período de setembro de 2005 a março de 2006. A produção de leite foi avaliada pelo método pesagem do bezerro anterior e posterior à mamada, do nascimento à desmama (189 dias), em intervalos de 21 dias. Para análise dos resultados foram incluídos no modelo estatístico como efeitos fixos, o resultado do diagnóstico de gestação (G) e nível de produção de leite (NPL): NPLa <1035,7 ± 36,6 kg The availability of net energy in the milk of Aberdeen Angus primiparous cows and his relationship with the calves performance was studied. Fourty seven cows, raised under a range condition, in Aceguá. RS county, were evaluated between September 2005 to April 2006. Milk production (PL) was estimated by before and after suckle method, from birth to weaning (189days), every 21 days. Effects studied were pregnancy (G), and milk production level (NPL): NPLa <1035.70 ± 36.65 kg

**Genetic characterization of three Nile tilapia (Oreochromis niloticus) strains**

El objetivo de este estudio fue analizar la diversidad genética de tres líneas de tilapia del Nilo (Oreochromis niloticus), mediante marcadores RAPDs. Se analizaron 90 individuos adultos (30 de cada línea) de dos piscifactorías ubicadas en las ciudades de Maringá (líneas Bouaké - B y GIFT G) y Guaíra (línea Chitralada - C), en el Estado del Paraná (Brasil). Los 13 oligonucleótidos seleccionados produjeron 72 fragmentos de los cuales 60 (83,3%) fueron polimórficos. Fueron observadas diferencias (p<0,05) en la frecuencia de 33 fragmentos, con 14 excluidos. Los resultados de variabilidad genética estimados por el porcentaje de fragmentos polimórficos y por el índice de diversidad genética de Shannon indicaron una alta variabilidad genética intra-poblacional. De acuerdo con el AMOVA, la mayor parte de la variación está dentro de cada línea. Este resultado se corroboró con los valores de FST, que mostraron una moderada diferenciación genética. También se constató que C y G fueron las líneas más semejantes genéticamente y que B y G presentaron menos genes en común. Los resultados de este estudio posibilitaran el correcto manejo re-productivo y genético de estas líneas de peces.

The aim of this study was to analyze the genetic diversity of three Nile tilapia (Oreochromis niloticus) strains, through the RAPD markers. Ninety adult individuals (30 of each strain) of two fish farms stations located in the Maringá (Bouaké - B and GIFT - G strains) and Guaíra (Chitralada C strain) cities, in the Paraná State (Brazil) were analyzed. The 13 selected primers yielded 72 fragments of which 60 (83.3%) were polymorphic. Differences (p<0.05) in the frequency of 33 fragments were observed, with 14 eliminated. The genetic variability results estimated by the percentage of polymorphic fragments and for the genetic diversity of Shannon index indicated a high intra-populational genetic variability. According with the AMOVA, most of the variation is within each strain. This result was corroborated with the FST values that showed a moderate genetic differentiation. It was also verified that C and G were the strains but similar genetically and that B and G presented less genes in common. The results of this study facilitated the correct reproductive and genetic management of these fish strains.

**Digestibility and ruminal parameters in beef cattle fed palisade grass (Brachiaria brizantha cv. marandu)**

O consumo e digestibilidades total e parcial da matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), fibras em detergente neutro (FDN) e ácido (FDA) e os parâmetros ruminais nitrogênio amoniacal e ácidos graxos de cadeia curta foram avaliados em bovinos de corte alimentados com Brachiaria brizantha cv. marandu aos 30 e 60 dias de rebrota em duas épocas do ano (janeiro e fevereiro). Os consumos de MS, MO e PB foram influenciados pela idade de rebrota da forrageira apresentando maiores valores aos 30 dias e também influenciados pela época do ano, sendo em fevereiro seu maior consumo pelos animais. A digestibilidade da MS foi em média 60,7 e 59,4% aos 30 e 60 dias de rebrota da forrageira, respectivamente, porém, demonstrou efeito de interação entre a idade de rebrota e a época do ano, mesmo comportamento observado para MO, com médias de 63,9 e 63% para as respectivas idades de rebrota. A digestibilidade da PB foi maior aos 30 dias de rebrota, média de 70,8%, que aos 60 dias, média de 57%. As digestibilidades da FDN e da FDA com efeito significativo para a interação entre a idade de rebrota e a época do ano, apresentaram aos 60 dias de rebrota na época de janeiro as menores médias, 54,8 e 48,5%, respectivamente e em fevereiro as maiores médias, 64,9 e 60,4%. A digestibilidade ruminal apresentou médias de 79,5, 86,2, 99,4 e 96,7% do total digerível para MS, MO, FDN e FDA, respectivamente, não sendo observados efeitos da idade de rebrota nem da época do ano. Após 2 horas da alimentação foi observado o pico de concentração de nitrogênio amoniacal no rúmen. A média da relação acetato:propionato:butirato observada foi 74:18:8(%).

This experiment aimed to evaluate nutrient intake, total and partial digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral (NDF) and acid (ADF) detergent fiber and ruminal parameters, ammonia concentration and volatile fatty acids, in beef cattle fed palisade grass (Brachiaria brizantha cv. marandu) at two regrowth ages, 30 and 60 days, at two times of year (January and February). The intake of DM, OM and CP was influenced by forage age of regrowth with high values for 30 days; this was influenced by time of year, being observed in February the higher intake by animals. DM digestibility average was 60.7 and 59.4% for 30 and 60 days of forage regrowth, respectively, however, was observed effect of interaction between regrowth and time of year, the same comportment was observed for OM, averages were 63.9 and 63% for respective ages of regrowth. CP digestibility was higher for 30 days, 70.8%, than for 60 days of regrowth, 57%. The NDF and ADF digestibilities were influenced by the interaction between regrowth and time of year; their average for 60 days of regrowth in January were respectively 54.8 and 48.5%, being the lower values and, in February, the higher values: 64.9 and 60.4%. The ruminal average digestibility was 79.5, 86.2, 99.4 and 96.7% of the total degradable for DM, OM, NDF and ADF, respectively. Effects of regrowth and time of year there were not recorded. Two hours after the morning meal was observed the ammonia ruminal concentration peak. The acetate:propionate: butirate ruminal ratio observed was 74:18:8(%).

**Control of ovarian follicular dynamics in early postpartum llama (Lama glama)**

Se evaluó el efecto del acetato de medroxiprogesterona (AMP, esponja intravaginal) con o sin inyección de benzoato de estradiol (BE) sobre el patrón de regresión folicular, la emergencia de la onda folicular y la tasa ovulatoria en llamas en posparto temprano y sin cría. El trabajo se realizó en la Estación Experimental de Altura del INTA de Abra Pampa, ubicada a 3484 msnm. Un total de 48 llamas adultas fueron categorizadas en lactancia temprana (n= 24, 30±4 días posparto, media±DE) y sin cría (n= 24). Cada hembra fue distribuida de acuerdo a la fase folicular (FF= crecimiento, estática o regresión) del folículo dominante (FD1) determinada por ultrasonografía ovárica desde 3 días previos al tratamiento. El día 0, todas las hembras recibieron una esponja intravaginal (150 mg de AMP) durante 8 días más 5 mg AMP (im) y la mitad de las hembras recibió aleatoriamente 2 mg de BE (im). Desde el día 0 hasta el 14, la respuesta ovárica fue monitoreada diariamente por ecografía. El día 12, las hembras que presentaron un folículo dominante >6 mm (FD2) de una nueva onda folicular fueron tratadas con GnRH (8 µg, im) para inducir la ovulación. Se midió la concentración plasmática de 17β-estradiol (desde el día 0 al 8) y progesterona (día 14) para confirmar la ovulación. Se utilizó un diseño factorial 2 x 2 x 3 (estado lactacional, tratamiento con o sin BE y fases foliculares). Se observó interacción entre el estado lactacional y la fase folicular sobre el patrón de regresión del FD1, atribuida a una mayor duración en hembras sin cría (6,0 días) que en las hembras con cría (3,5 días) durante la fase estática. El día de emergencia del FD2 fue diferente (p<0,05) entre tratamientos (con BE= día 6,5±0,6 y sin BE= día 4,2±0,5). El diámetro del FD2 al día 12 fue afectado (p<0,05) por el tratamiento (con BE= 6,4±0,3 mm vs. sin BE= 8,2±0,3 mm) y el estado lactacional (sin cría= 8,0±0,4 mm vs. lactancia temprana= 6,6±0,3 mm). La tasa ovulatoria total (hembras con ovulación/hembras tratadas) obtenida en el tratamiento con BE (45,8%) fue menor (p<0,05) que en el tratamiento sin BE (82,6%). En conclusión, el tratamiento con AMP (intravaginal e inyectable) combinado con una inyección de BE, demoró la emergencia de una nueva onda folicular en aproximadamente dos días y el diámetro del FD2 al día 12 y la tasa ovulatoria fueron menores que en hembras sin BE. La lactancia estuvo asociada con desarrollo folicular deprimido, sin afectar al porcentaje de hembras que ovuló posterior al tratamiento con AMP.

The effect of treatment with medroxiprogesterone acetate (MPA, intravaginal sponge) combined with or without injection of estradiol benzoate (EB) on the patterns of follicular regression, follicular wave emergence and ovulation rate in early postpartum and non-lactating llamas was evaluated. This work was carried out at the Experimental Station of Altitude INTA Abra Pampa (3484 m above sea level). A total of 48 adult females were categorized as lactating (n= 24; 30±4 d postpartum, mean±SD) or non-lactating (n= 24). Each one was distributed according to the follicular phase (FP= growing, static or regressing) of dominant follicle (DF1) determined by daily ovarian ultrasonography from 3 days before treatment. At day 0, intravaginal sponge (150 mg MPA) was inserted to all llamas for 8 days plus 5 mg MPA (im). Half of the females randomly received 2 mg of EB (im). The ovarian response was monitored daily by ultrasonography from day 0 to day 14. At day 12, females having a new dominant follicle >6 mm (DF2) were treated with GnRH (8 µg, im) to induce ovulation. Blood samples were collected to determine plasma estradiol-17β (from day 0 to day 8) and progesterone (day 14) concentrations to confirm ovulation. Factorial design 2 x 2 x 3 (lactational status, treatment with or without EB and follicular phases) was used. There was lactational status by FP interaction on the regression patterns of DF1 attributed to greater duration in non-lactating females (6.0 days) than for lactating females (3.5 days) in the follicular static phase. The day (mean±SEM) of follicular wave emergence was different (p<0.05) between treatments (with EB= day 6.5±0.6 vs. without EB= day 4.5±0.5). At day 12, the DF2 diameter (mean±SEM) was affected (p<0.05) by the treatment (with EB= 6.4±0.3 mm vs. without EB= 8.2±0.3 mm) and the lactational status (nonlactating= 8.0±0.4 mm vs. lactating= 6.6±0.3 mm). The total ovulation rate (females with ovulation/ treated females) in EB-treated females (45.8%) was lower (p<0.05) than non-treated females (82.6%). In conclusion, the MPA treatment (intravaginal plus intramuscular) combined with injection of EB approximately delayed in two days the emergence of a new follicular wave. Therefore, follicular diameter at day 12 and the ovulation rate were lower than no EB treatment. Lactation was associated with depressed follicular development, however, it did not affect the ovulation rate.

**Oocyte recovery and in vitro production from cows stimulated with either FSH or ECG**

Avaliou-se a recuperação de oócitos e produção de embriões in vitro de 42 vacas, mestiça Nelore proveniente de grupo genético homogêneo, com idade de 4 a 9 anos, com peso médio de 420 kg, estimuladas com FSH ou eCG. Estas foram distribuídas em três grupos: grupo 1, controle (n=14), apenas OPU, grupo 2, tratadas com 1400 UI de eCG, em dose única seguida de aspiração folicular (OPU) (n= 14); e, grupo 3, tratadas com 120 UI de FSH, administrados com intervalo de 12 horas em quatro doses seguida de OPU (n= 14). Todos os grupos receberam implante auricular contendo 3 mg de Norgestomet no primeiro dia (D0) associado a administração de 2 mg de benzoato de estradiol via intramuscular. No sétimo dia (D7) foram retirados todos os implantes e na sequência foram realizadas as aspirações ovarianas das vacas do grupo 1. O grupo 2 recebeu a aplicação de eCG no quinto dia e a OPU foi realizada no D7. Já o grupo 3 recebeu o tratamento com FSH no quinto e sexto dia, e foram aspiradas em D7. O procedimento de aspiração folicular foi realizado via transvaginal guiada por ultrassom. Foram realizadas 42 aspirações com obtenção de 627 oócitos, sendo 502 viáveis e 125 inviáveis. Realizou-se a maturação e fecundação in vitro. Avaliaram-se as taxas de clivagem, blastocisto e eclosão. Não houve diferenças significativas (p>0,05) nos parâmetros avaliados entre os grupos. Conclui-se que o estímulo ovariano com FSH ou com eCG nas doses utilizadas, foram insuficientes para incrementar o número e a qualidade de oócitos viáveis submetidos a fertilização in vitro para produção de embriões.

It was evaluated the oocyte and embryo in vitro production of 42 Nellore mixed breed cows (Bos taurus indicus) come from de same genetic group, aging from 4 to 9 years, with mean body weight of 420 kg, stimulated with FSH and eCG. The animals were distributed into three groups: group 1, control (n= 14), only with follicular aspiration (OPU); group 2, treated with 1400 UI of eCG in a single dose plus OPU (n= 14); and group 3, treated with 120 UI of FSH administered four times plus OPU with 12 h of interval (n= 14). All groups received auricular implant with 3 mg of Norgestomet on the first day (D0) associated with 2 mg of estradiol benzoate intramuscularly. At the seventh day (D7) the implants were removed and the ovarian aspirations were realized on the cows of group 1(OPU). Group 2 had the eCG applied at the fifth day and the OPU was performed at D7. The animals from group 3 were treated with FSH at fifth and sixth day and the aspiration occurred at D7 (OPU). The follicular aspiration procedure was done via transvaginal guided with ultrasound. It was performed 42 aspirations obtaining 627 oocytes, where 502 were viable and 125 non-viable. Then, it was realized the in vitro maturation and fecundation. The cleavage, blastocyst and eclosion rate were evaluated. There were no significant difference (p>0.05) at these parameters between the groups. In conclusion, the gonadotrophic stimulation with FSH and eCG, at the doses used in this study, was insufficient to increase the quality of the viable oocytes submitted to in vitro fertilization to produce embryos.

Chemical composition and fermentative characteristics of sugar cane silages containing babassu meal

Objetivou-se avaliar o efeito da adição do farelo de babaçu na composição química e características fermentativas de silagens de cana-deaçúcar. Foram avaliadas três concentrações de adição do farelo de babaçu (0; 15 e 30% na matéria natural) em um delineamento inteiramente casualizado com quatro repetições cada. Como silos experimentais foram utilizados 12 baldes plásticos, providos de torneira de filtro para permitir a saída dos gases produzidos durante a fermentação. Os silos foram abertos com 45 dias de ensilagem e amostras foram colhidas para determinação dos teores de matéria seca (MS), de proteína bruta (PB), de fibra em detergente neutro e ácido (FDN e FDA), de hemicelulose (Hem), valores de pH, acidez total titulável (ATT), perdas por gases (PG) e por efluentes (PE). A adição de farelo de babaçu elevou os teores de MS (38,4% e 40,6%), de PB (7,8 e 8,9%), de FDN (68,8% e 70,9%) e de FDA (43,0% e 45,1%), respectivamente com a adição de 15 e 30% de subproduto. O pH não foi influenciado pela adição do farelo de babaçu, apresentando valor médio de 4,4. Já os percentuais de ATT foram elevados em 89,2%. Por sua vez as PG e PE foram reduzidas em 44,8 e 58,8%, respectivamente. Apesar da adição do farelo de babaçu ter contribuído para a melhoria dos parâmetros fermentativos e da concentração de PB das silagens de cana-de-açúcar, a utilização do mesmo como aditivo torna-se limitada devido ao aumento dos teores de fibra que esse subproduto proporciona às silagens, depreciando valor nutritivo das mesmas.

The objective of this trial was to evaluate the effect of babassu meal addition on chemical composition and fermentative characteristics of sugar cane silages. The addition of three concentrations of babassu meal (0; 15 and 30% in fresh matter) was evaluated in a completely randomized design with four replicates. As experimental silos 12 plastic buckets were used, provided with filter closing to allow the exit of fermentation gases. After 45 days, the silos were opened and samples were taken for the determination of dry matter (MS), crude protein (PB), neutral and acid detergent fibers (FDN, FDA) and hemicelluloses (Hem) content, pH values, total acidity quantification (ATT), losses by gases (PG) and effluents (PE). The addition of babassu meal increased the MS contents (38.4% e 40.6%), PB (7.8 e 8.9%), FDN (68.8% e 70.9%) and FDA (43.0% and 45.1%), respectively, with the addition of 15 and 30% of the by-product. The pH values, averaged 4.4, were not affected by the addition of babassu meal. The percentage of ATT increased 89.2%. PG and PE were reduced in 44.8 and 58.8%, respectively. The addition of babassu meal have contributed to the improvement of fermentative parameters and the concentration of CP in the sugar cane silages. However, its use as additive becomes limited due to the increase in fiber content that provides to the silages, depreciating its nutritive value.

**Production, chemical composition and chlorophyll index of Brachiaria spp. after the intercrop with corn**

Avaliou-se o efeito da adubação com 0, 50, 100 e 200 kg/ha de N aplicadas em cada um dos 4 intervalos de crescimento no inverno/primavera sobre a produtividade de matéria seca em 30 dias (PMS), o índice de clorofila foliar (ICF) e os teores de nutrientes digestíveis totais (NDT), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e lignina, bem como, as equações de correlação do ICF com a PMS e o teor de PB nos capins marandu e ruziziensis após o consórcio com milho em um Latossolo Vermelho Distroférrico sob irrigação. As maiores PMS ocorreram com o aumento do fotoperíodo, no entanto, houveram respostas diferenciadas deste atributo ao longo dos cortes, entre e dentre os capins quanto à adubação nitrogenada. Em sistema de integração lavoura-pecuária irrigado sob condições de cerrado é tecnicamente viável o estabelecimento dos capins marandu e ruziziensis pelo consórcio com o milho no momento da semeadura ou por ocasião da adubação nitrogenada de cobertura. Na ausência de adubação N foi produzida quantidade satisfatória de forragem, com PMS média de 1733 kg/ha, na época de maior escassez de volumoso para os animais (inverno/primavera). No entanto, a adubação N, após a colheita do milho elevou a PMS e melhorou a composição bromatológica dos capins, com aumento do ICF e dos teores de PB e NDT, e reduziu os teores de FDN e FDA no inverno/ primavera. As melhores equações de correlação em função do ICF foram logarítima para a PMS e potencial para a PB do capim-marandu e potencial para ambos os atributos do capim-ruziziensis.

We evaluated the effect of fertilization with 0, 50, 100 and 200 kg/ha of N, applied in each four growth intervals in the winter/spring season on dry matter yield in 30 days (DMY), leaf chlorophyll index (LCI) and total digestible nutrients (TDN), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents, and correlation equations of LCI with DMY and CP content in the marandu and ruziziensis grasses after intercrop arrangements with corn in Red Latosol (Oxisol) under irrigation. The major DMY occurred with photoperiod increasing, however, there were different responses to this attribute over of growth intervals, between and among the grasses with the N fertilization. In irrigated croplivestock integration under savannah soil is technicality viable the cultivation of marandu and ruziziensis grasses, established by intercrop with corn at sowing or at the N fertilization. As even, in the N fertilization absence, produced satisfactory amounts of forage, with 1733 kg/ha (DMY), at the time of greatest scarcity of roughage to animals (winter/spring season). However, after the corn harvest, the N fertilization increase the DMY and improves the chemical composition, increasing the LCI, and CP and TDN contents, and decreasing NDF and ADF contents in the winter/spring season.The best correlation equations in function of LCI were logatithmica for DMY and potential for CP of the marandu grass and potential for both attributes of the ruziziensis grass.

Effect of the use of enzymatic complex in diets for broilers

Objetivou-se com este experimento avaliar os efeitos da suplementação de carboidrases de forma individual (α-amilase) ou associada ao complexo enzimático (α-galactosidase, galactomananase, xilanase e β-glucanase), sobre o desempenho, rendimento de carcaça e viabilidade econômica em rações para frangos de corte. Foram utilizados 576 pintos de corte, fêmeas, da linhagem Cobb, distribuídos em delineamento inteiramente casualizado constituído por 4 tratamentos e 6 repetições de 24 aves cada. As rações foram formuladas à base de milho e farelo de soja, sendo os tratamentos constituídos por CP= ração-controle-positivo; CN= ração-controle-negativo, com redução em 35 Kcal na fase inicial e 70 Kcal/kg de ração para as fases de crescimento e final; RA= ração reformulada com amilase exógena (isonutriente a CP) e RE= ração reformulada com α-amilase exógena e complexo enzimático (isonutriente a CP). A matriz nutricional da amilase exógena na ração RA foi de 116,67 Kcal/kg na fase inicial e 233,34 Kcal/kg nas fases de crescimento e final. Para a ração RE a matriz nutricional da amilase exógena foi de 116,67 Kcal/ kg na fase inicial e 200,00 Kcal/kg nas fases de crescimento e final. Houve valoração dos ingredientes milho e farelo de soja em 1,5 e 6% na EMAn, respectivamente e 2% nos aminoácidos limitantes para ambos ingredientes. As médias de desempenho foram avaliadas nos períodos de 1 a 21, 1 a 35 e 1 a 42 dias. A avaliação de rendimento de carcaça e cortes, bem como a viabilidade econômica foi avaliada aos 42 dias. O consumo de ração, em todos os períodos, não diferiu significativamente entre os tratamentos avaliados (p>0,05). Da mesma forma, o ganho de peso no período total, de 1 a 42 dias, não ocasionou diferença entre os tratamentos. A pior conversão alimentar e fatores de produção (p<0,05) foram obtidos pelos animais submetidos à ração com complexo enzimático. Não houve diferença significativa no rendimento de carcaça e de nenhum corte avaliado (p>0,05). A utilização de complexo enzimático associado à enzima exógena α-amilase piora o desempenho e gera mesma resposta econômica na produção de frangos de corte, sem alterar o rendimento de carcaça e de seus cortes.

This work was carried out in order to evaluate the effects of supplemental carbohydrases individually (α-amylase) or associated with the enzyme complex (α-galactosidase, galactomananase, xylanase and β-glucanase) on performance, carcass yield and economic viability in diets for broiler. Were used 576 females chicks, Cobb lineage, distributed in a completely randomized design consisting of 4 treatments and 6 replicates of 24 birds each plot. The diets were formulated based on corn and soybean meal, and the treatments consisted of PC= positive control diet NC= negative control diet with 35 kcal reduction in the initial stage and 70 Kcal/kg of feed for the growth and final stages RA= diet reformulated with exogenous amylase (isonutriente to PC) and RE= diet reformulated with exogenous α-amylase and enzyme complex (isonutriente to PC). The nutritional matrix exogenous amylase for RA in the diet was 116.67 Kcal/kg in the initial stage and 233.34 Kcal/kg in the growth and final stages. The nutritional matrix exogenous amylase for RE was 116.67 Kcal/kg at the initial and 200.00 Kcal/kg in the growth and final stages. There was appreciation of the ingredients corn and soybean meal at 1.5 and 6% in AME, and 2% respectively in limiting amino acids for both ingredients. The average performance were evaluated from 1 to 21, 1 to 35 and 1 to 42 days. Feed intake in all periods, did not differ significantly between treatments (p>0.05). Likewise, weight gain in the total period, 1-42 days, caused no difference between treatments. The worst feed conversion and production factors (p<0.05) were observed in animals treated with diets with the enzyme complex. There was no significant difference in carcass yield and no cutting evaluated (p>0.05). The evaluation of carcass yield and cuts, and the economic viability were evaluated at 42 days. The use of enzyme complex associated with exogenous enzyme α-amylase worsens performance and generates the same economic response in the production of broilers, without changing the carcass and its cuts yield.

Early weaning in beef cows treated with intravaginal progesterone and their reproductive performance

El objetivo del presente trabajo fue determinar el efecto del momento del destete precoz (DP) en vacas con cría tratadas con progesterona intravaginal sobre las características de la ovulación y la eficiencia reproductiva. Se realizaron 2 experimentos con animales de raza Hereford y Polled-Hereford. Exp.1: 38 vacas de baja condición corporal (3,3±0,8; media±DE; escala de 1 a 9) con 55,7±8,8 días posparto y Exp. 2: 35 vacas de alta condición corporal (5,4±0,9) con 57,5±15,9 días posparto. El día 0 todos los animales recibieron un dispositivo intravaginal (DIV) impregnado con 0,5 g de progesterona más 2 mg de benzoato de estradiol (BE; im). El día 8 se retiró el DIV, se aplicó 500 µg de cloprostenol sódico (im) y 24 horas después se aplicó 1 mg de BE. Los animales fueron distribuidos aleatoriamente a 4 tratamientos: T1): DP diez días antes de colocar el DIV; T2): DP el día de colocación del DIV; T3): DP el día del retiro del DIV y T4): Control con cría al pie. Todas las vacas fueron inseminadas a tiempo fijo a las 56 h del retiro de los DIV. En ambos experimentos se evaluó mediante ultrasonografía la dinámica folicular, el momento y distribución de las ovulaciones y la preñez. Se determinó la concentración plasmática de progesterona para evaluar la funcionalidad y la vida media del cuerpo lúteo generado por la ovulación inducida en los vientres que no resultaron preñados. En vacas de baja condición corporal (Exp.1), el diámetro del folículo dominante al retiro del DIV en el tratamiento T2 (11,2±2,5 mm) fue mayor (p<0,05) que en el tratamiento T3 (7,3±2,0 mm), no registrándose diferencias con los tratamientos T1 y T4 (10,3±2,4 y 8,2±2,8 mm, respectivamente). La tasa de ovulación fue mayor (p<0,05) en los tratamientos T1 y T2 (77,8% y 88,9%, respectivamente) que en los tratamientos T3 y T4 (40% en ambos casos). La tasa de preñez en el tratamiento T2 (77,8%) fue superior (p<0,05) al resto de los tratamientos evaluados (T1= 55,6%, T3= 30% y T4= 20%). En vacas de alta condición corporal (Exp. 2) no se observaron diferencias (p>0,05) entre tratamientos en ninguno de los parámetros evaluados. La vida media del cuerpo lúteo de las vacas no gestantes fue normal, independientemente del tratamiento aplicado y de la condición corporal de las mismas. Este estudio permitió determinar que, en vacas de baja condición corporal, el DP realizado 10 días antes o al inicio de un tratamiento con progesterona/estrógenos produjo un mayor tamaño del folículo dominante (preovulatorio) y una mayor tasa de ovulación. Sin embargo, la tasa de preñez sólo fue mejorada cuando el destete se realizó al inicio del tratamiento hormonal en las vacas de baja condición corporal asignadas al Exp.1.

The objective of the present study was to determine the effect of early weaning time on the ovulation characteristics and the reproductive efficiency of treated beef cows with an intravaginal progesterone device (DIV). Two experiments were performed utilizing Hereford and Polled Hereford cows. Exp. 1: 38 low body condition score cows (BCS; 3.3±0.8, mean±SD, range from 1 to 9) with 57.5±8.8 days postpartum and Exp. 2: 35 high BCS (5.4±0.9) cows with 57.5±15.9 days postpartum. On day 0, all cows received an DIV containing 0.5 g progesterone plus 2 mg of estradiol benzoate i.m. (EB). On day 8, the DIV was removed and 500 ìg cloprostenol was injected i.m., followed by administration of 1 mg of EB i.m. 24 h later. Animals were assigned randomly to each of four treatments:T1) Early weaning at 10 days before the DIV insertion; T2) Early weaning the day of the DIV insertion; T3) Early weaning the day of withdrawal DIV and T4) No early weaning, calves were left with their respective mothers throughout the study period. All cows were fixed-time artificially inseminated 56 h after the DIV removal. In Exp. 1 and 2, follicular dynamics, time and distribution of the ovulation and pregnancy were evaluated by means of transrectal ultrasonography. Plasma progesterone concentrations were determined to evaluate the functionality and lifespan of the corpus luteum generated by the induced ovulation. At the time of the DIV removal, the dominant follicle diameter was larger (p<0.05) in T2 (11.2±2.5 mm) than T3 (7.3±2.0 mm) in cows with low BCS (Exp. 1), but did not differ with T1 and T4 (10.3±2.4 and 8.2±2.8, respectively). The T1 and T2 treatments presented a higher (p<0.05) ovulation rate than T3 and T4 (77.8; 88.9; 40 and 40% respectively). Pregnancy rate was higher in T2 (77.8%) than in the rest of treatments (T1= 55.6%, T4= 30%, T4= 20%). In Exp. 2, no differences were found among treatments for all the evaluated parameters. In non-pregnant cows the corpus luteum had a normal lifespan, independently of treatment or BCS. In summary, early weaning performed 10 days before or the day of treatment start with progesterone/estrogen increased dominant follicle diameter (pre-ovulation) and ovulation rate in low BCS cows. Nevertheless, pregnancy rate was only improved when early weaning was done the day of the DIV insertion in the low BCS cows assigned to Exp. 1.

Growth performance and digestibility of feedlot Zebu steers fed yeast and monensin

Foi avaliado o efeito da adição de cultura de leveduras vivas (Saccharomyces cerevisiae, cepa 1026), da monensina e da combinação dos dois aditivos em dietas de alto concentrado, sobre as características de desempenho de novilhos confinados e sobre a digestibilidade aparente da dieta. Novilhos Nelore (339 kg PV, 20 meses de idade, n= 72) foram alimentados por 84 dias com uma dieta basal (2,58 Mcal EM/kg MS, 14% PB) sem aditivos (controle) ou suplementada com levedura (0,6 g de Beef Sacc®/kg de matéria seca), monensina (0,3 g de Rumensin®/kg de matéria seca) ou a adição de ambos aditivos para avaliar o desempenho em confinamento por meio da mensuração individual do consumo, ganho de peso e medidas de ultra-som da espessura de gordura subcutânea nos músculos Longissimus (12ª costela) e Biceps femoris. Outros quatro novilhos foram designados aleatoriamente aos tratamentos seguindo um delineamento em quadrado latino a fim de determinar os efeitos dos tratamentos sobre a digestibilidade aparente da matéria seca, proteína bruta, fibra em detergente neutro e ácido da dieta. Não houve efeitos dos aditivos sobre o consumo de matéria seca e na taxa de aumento da espessura de gordura subcutânea e em área do músculo Longissimus, entretanto, a levedura tendeu a diminuir o ganho de peso médio diário e aumentar a conversão alimentar (p<0,10). Os coeficientes de digestibilidade aparente das frações estudadas não foram influenciados pela adição dos aditivos na dieta (p>0,10). A adição de leveduras vivas, monensina ou da combinação de ambos pode não ser importante sobre a terminação de bovinos de corte confinados com dieta de alto concentrado.

The effect of adding live yeast culture (Saccharomyces cerevisiae, strain 1026), monensin or the combination of both additives to high grain diets on feedlot performance and digestibility of steers, was studied. Nellore steers (n= 72, 339 kg BW, 20 months-old) were fed for 84 days a basal ration (2.58 Mcal EM/kg DM, 14% CP) without additives (control), or with yeast culture (0.6 g Beef Sacc®/ kg DM), monensin (0.3 g Rumensin®/ kg DM) or the combination of both additives to evaluate feedlot performance through individual measurements of dry matter intake, average daily gain and ultra-sound scanning of carcass subcutaneous fat thickness upon Longissimus (12th rib) and Biceps femoris muscle and rib eye area. Other four steers were randomly allotted to one of the treatments in a 4 x 4 latin square design in order to assess digestibility of dry matter, crude protein, neutral detergent fiber and acid detergent fiber fractions of the diet. There were no effects of additives on dry matter intake and rate of growth of carcass fat thickness and rib eye area. Yeast culture tended to decrease average daily gain and increase feed conversion (p<0.10). Digestibility was not affected by treatments (p>0.10). Supplementation of live yeast culture, monensin or the combination of both may not be important on finishing beef steers fed high grain diets in feedlot.

Relations among the subjective and computer-assisted variables of ram sperm motility

En este trabajo se analizan las relaciones existentes entre las variables de movilidad espermática en eyaculados de moruecos de raza Île de France a lo largo de un año, obtenidas mediante análisis subjetivo y por el sistema informatizado ISAS® (Integrated Semen Analysis System). Los resultados muestran una fuerte asociación entre parámetros del mismo tipo, siendo el coeficiente de correlación r>0.80 (p<0,01) cuando la relación se produce entre velocidad rectilínea (VSL) y velocidad media (VAP), entre el porcentaje de espermatozoides estáticos (EST) y rápidos (RAP) y entre movilidad masal (MM) y movilidad individual (MI). Las asociaciones que aparecen entre grupos de distinta clase (velocidades vs. variables expresadas en porcentaje) son moderadas o bajas en el caso de que existan; sin embargo también son elevadas las que aparecen entre el índice de linealidad (LIN) y la amplitud del desplazamiento lateral de la cabeza (ALH) (r= -0,866, p<0,01) y entre MI y RAP (r= 0,799, p<0,01). A la vista de los resultados se puede decir que existe concordancia entre los parámetros determinados de manera subjetiva y los aportados por el sistema informatizado CASA, siendo MI el parámetro subjetivo que mejor explica las variables obtenidas por ISAS®.

The present study examines the existing relationships among sperm motility variables in ejaculates from Île de France rams throughout a year, obtained by means of both subjective analysis and computer-assisted system ISAS® (Integrated Semen Analysis System). The results show a strong association among parameters of the same kind, being the correlation coefficient r>0.80 (p<0.01) when the relationship occurs between linear velocity (VSL) and average path velocity (VAP), between porcentage of inmovil spermatozoa (EST) and rapid espermatozoa (RAP), and between masal motility (MM) and individual motitity (MI). The relationships among groups of a different kind (velocities vs. variables expressed as percentages) are moderate or low, when existent; however, those between lineatity (LIN) and lateral head displacement (ALH) (r= -0.866, p<0.01) and between MI and RAP (r= 0.799, p<0.01) are high. In view of the results, it may be stated that there exists a concordance between the parameters subjectively established and those provided by computer-assisted system CASA, being MI the subjective parameter that best explains the variables obtained by ISAS®.

Evaluation of cold water and vitamin C on broiler growth during hot-dry season in sw Nigeria

A study to determine effects of cold water and vitamin C on growth performance in 216 Anak 2000 broiler chickens was carried out during hotdry season in the SW Nigeria. The minimum, maximum and mean temperatures during the experiment were 19.4, 35.8 and 27.6ºC respectively while the relative humidity was 72.6%. The broilers, Anak 2000 at d 28 were allotted to two groups offered either ordinary water (29.5ºC) or chilled water (8.0ºC) for four weeks. Each group was divided into two. Each half received either 0 or 500 mg vitamin C per litre in drinking water in 2 x 2 factorial arrangement. There were 3 replicates with 18 birds per replicate. Data on daily water intake (DWI), weekly feed intake (WFI), final liveweight (FLW), weekly weight gain (WWG), total weight gain (TWG), feed conversion ratio (FCR), percentage survival (SURV), and relative weights of breast meat, liver, spleen, gizzard, drumstick, thigh, heart and wing were subjected to analysis of variance. Water temperature had no significant effect on DWI, WFI, FCR and SURV. However, offering broiler chickens cold drinking water resulted in significantly higher WWG (p<0.001), TWG (p<0.001), FLW (p<0.001) and relative weight of spleen (p<0.001) compared to water at ambient temperature. Addition of 500 mg vitamin C per litre water increased significantly the relative weights of breast meat compared to 0 mg vitamin C. Other parameters were affected by vitamin C. There were not interaction between water temperature and addition of vitamin C on growth parameters examined in this study. It can therefore be concluded that offering cold water to broiler chickens during hot-dry season increases weight gain and spleen but reduced wing size. Though addition of vitamin C could not raised growth rate in broilers during hot-dry season, the breast meat yield was improved.

Durante la estación cálida-seca en el SW de Nigeria se realizó un estudio para determinar los efectos del agua fría y la vitamina C sobre el crecimiento de 216 broilers Anak 2000. Las temperaturas mínima, media y máxima durante el experimento fueron 19,4; 35,8 y 27,6ºC respectivamente y la humedad relativa fue de 72,6%. El día 28, los pollos fueron divididos en dos grupos a los que se suministró agua a temperatura normal (29,5ºC) o agua enfriada (8,0ºC) durante cuatro semanas. Cada grupo fue dividido en dos, recibiendo cada mitad 0 o 500 mg de vitamina C por litro de agua de bebida en un diseño factorial 2 x 2 se realizaron tres repeticiones con 18 aves por repetición. Los datos sobre ingestión diaria de agua (DWI), ingestión semanal de alimento (WFI), peso vivo final (FLW), ganancia de peso semanal (WWG), ganacia total de peso (TWG), tasa de conversión de alimento (FCR), porcentaje de supervivencia (SURV) y pesos relativos de pechuga, hígado, bazo, molleja, pata, muslo, corazón y ala, fueron sometidos al análisis de varianza. La temperatura del agua no tuvo efecto significativo sobre DWI, WFI, FCR y SURV. Sin embargo el consumo de agua fría por los pollos se tradujo en un aumento WWG (p<0,001), TWG (p<0,001), FLW (p<0,001) y peso relativo del bazo (p<0,001) en comparación con el consumo de agua a temperatura ambiente. La adición de 500 mg de vitamina C por litro de agua incrementó significativamente el peso relativo de la pechuga, comparado con el suministro de 0 mg de vitamina C. Otras variables fueron influenciadas por la vitamina C. No se registró interacción entre la temperatura del agua y la vitamina C sobre los parámetros de crecimiento examinados en este estudio. Puede concluirse que el suministro de agua fría a los pollos durante la estación cálida-seca aumenta la ganacia de peso y del hígado, pero redujo el tamaño del ala. Aunque la adición de vitamina C no aumentó la tasa de crecimiento en broilers durante la estación cálida-seca, el rendimiento de la pechuga mejoró.

Development of the digestive tract of broilers fed diets containing sweet potato meal

Foi avaliado o desenvolvimento do sistema digestório de frangos de corte alimentados com farinha de batata doce em substituição parcial ao milho, com ou sem suplementação de um complexo enzimático. Cento e cinquenta pintos de um dia de idade, machos, da linhagem Cobb, foram alojados em 40 boxes de duas baterias metálicas onde permaneceram até os 28 dias de idade. O delineamento experimental foi o de blocos ao acaso em arranjo fatorial 3 x 2, com três níveis de farinha de batata doce (0, 20 e 40%) e dois do complexo enzimático (0 e 200 g/ton), com 5 repetições de 5 aves por tratamento. Aos 14, 21 e 28 dias de idade, foram pesadas e sacrificadas por deslocamento crânio-cervical, 5 aves por tratamento, para avaliação alométrica do coração, fígado, proventrículo e moela e biométrica do duodeno, jejuno, íleo, cólon-reto e cecos. Os dados foram submetidos à análise da variação e regressão polinomial. O aumento de farinha de batata doce em substituição ao milho na dieta de frangos de corte interfere negativamente no peso corporal e no desenvolvimento de órgãos. A suplementação do complexo enzimático não influencia a alometria de órgãos e a biometria intestinal dos frangos de corte.

The development of the digestive tract of broilers fed diets containing sweet potato meal in partial replacement of corn, with or without enzyme supplementation. One hundred and fifty a day old, male, Cobb chickens, were allocated in 40 pens of two batteries where they remained until 28 days old. A completely randomized experimental design was used. Treatments were distributed in a 3 x 2 factorial arrangement, in which three levels of sweet potato meal (0, 20 and 40%) and two levels of enzyme complex (0 or 200 g/ton), with a total of 5 replicates of 5 birds per treatment. At 14, 21 and 28 days of age, 5 birds per treatment were slaughtered by cervical deslocation to evaluate the allometric development of heart, liver, proventriculus ans gizzard and biometric development of duodenum, jejunum, ileum, colon, rectum and ceca. Data were analyzed by analyse of variance and polynomial regression. The use of increasing dietary levels of sweet potato meal bring about a decrease in body weight and in organ development. The enzyme supplementation does not influence the allometry of organs and intestinal biometric of broilers.

Discriminant analysis of sexual dimorphism in morphological traits of African Muscovy ducks

Sexual dimorphism was examined in 221 randomly selected adult African Muscovy ducks extensively reared in north central Nigeria using univariate and multivariate measures of body size and skeletal proportions. The body parameters investigated included body weight, 8 primary linear body measurements [breast circumference (BTC), thigh circumference (THC), body length (BDL), bill length (BLL), neck length (NKL),foot length (FTL), total leg length (TLL) and wing length (WNL)] and 4 morphological indices (massiveness, stockiness, long-leggedness and condition index). The univariate analysis showed male dominance (p<0.05) in all the morphometric measurements, with the exception of stockiness and longleggedness where significantly higher mean values were recorded for females. Low, moderate and high positive and negative correlations among the body size and shape characters of the ducks were recorded. The canonical discriminant analysis on body weight and primary linear body measurements revealed that wing length was the most discriminating variable between the sexes, followed by body weight, neck circumference, total leg length, body length and foot length respectively. Three other variables not qualified to enter the model were expunged. The single discriminant function obtained (D= -3.116 + 0.280WNL+ 0.921BWT + 0.191NKL - 0.196TLL 0.063BDL - 0.283FTL) correctly classified 91.4% of individuals of known-sex ducks. This might aid in ecological studies, conservation and improvement of the indigenous ducks.

Se estudió el dimorfismo sexual en 221 patos, Muscovy Africanos, adultos, seleccionados al azar, explotados extensivamente en la región norte centro de Nigeria, empleando para ello medidas uni y multivariadas del tamaño corporal y proporciones del esqueleto. Los parámetros corporales investigados incluyeron: peso corporal, ocho medidas lineales corporales (circunferencia de la pechuga, BTC; circunferencia del muslo, THC; longitud del cuerpo, BDL; longitud del pico, BLL; longitud del cuello, NKL; longitud del pie, FTL; longitud total de la pata, TLL y longitud del ala, WNL) y cuatro índices morfológicos (masividad, solidez, largura de la pata e índice de condición). El análisis univariado mostró la dominancia del macho (p<0,05) en todas las medidas morfométricas, salvo para solidez y largura de la pata en los que se registraron valores medios significativamente más altos para las hembras. Correlaciones positivas y negativas, bajas, moderadas o altas, fueron encontradas entre tamaño corporal y caracteres morfológicos de los patos. El análisis discriminan-te canónico para el peso corporal y medidas lineales primarias del cuerpo, reveló que la longitud del ala fue la variable más discriminante entre sexos, seguida del peso corporal, circunferencia del cuello, longitud total de la pata, longitud del cuerpo y longitud del pie respectivamente. Otras tres variables no cualificadas para entrar en el modelo fueron eliminadas. La función discriminan-te simple obtenida (D= -3,116 + 0,280WNL+ 0,921BWT + 0,191NKL - 0,196TLL - 0,063BDL 0,283FTL), permitió clasificar correctamente 91,4% de los individuos de la muestra de patos de sexo conocido. Esto puede ser útil en estudios ecológicos y de conservación y mejora de patos indígenas.

Predicting equations for tisular composition in carcass of two Canary sheep breeds

Se estudiaron dos razas ovinas locales: la Canaria y la Canaria de Pelo. Los animales se criaron en sistema intensivo. Se consideraron dos pesos vivos de sacrificio (15,30 ± 0,67 y 24,23 ± 0,69 kg) y dos sexos. Se determinaron las correlaciones entre los porcentajes de los tejidos de la canal y los de las piezas obtenidas de la media canal izquierda. Se obtuvieron ecuaciones para predecir la composición tisular de la canal, a partir de las piezas con mejores coeficientes de regresión. El costillar fue la pieza que mejor predijo el músculo y la grasa. La pierna fue mejor predictora para el hueso.

Two local sheep breeds were studied: the Canarian and the Canarian Haired. Animals were intensively reared. Two slaughter weights were considered (15 and 24 kg live weight). Correlations among carcass tissue percentage and tissue percentage in the seven joints in the left halfcarcass were obtained. Equations were obtained to predict carcass tissue composition using most correlated joints. Ribs was the best predictor joint of muscle and fat. Leg was the best predictor of bone.

Rural women management in the northeastern Brazilian semiarid

Analisa-se a participação micro-econômica da mulher de diferentes comunidades rurais no Município de Tauá, Microrregião do Sertão dos Inhamuns, Ceará (Comunidades do Junco, Tapera, Lustal 1, Lustal 2, Tiassol e Queimadas), no que diz respeito ao manejo de tarefas rurais. As Unidades de Produção Agrária Familiar (UPAF) estudadas nessas comunidades representam 75,7% das mulheres participantes (n= 103) do Projeto de Pesquisa. O total de UPAFs residentes nas 6 comunidades sob estudo ascende a 305, portanto, o presente trabalho abrangeu 25,5% das mulheres rurais do distrito. Os dados coletados in situ através de questionários, foram submetidos à análise estatística descritiva, multifatorial e de variância. A mulher rural dessas comunidades encontra-se predominantemente na faixa de 45,52 anos com prole em idade escolar e não possui educação formal. A mulher surge como principal responsável pelas aves, suínos e horta-pomar e está envolvida em atividades com o roçado e com gado ruminante minimamente. Como os não ruminantes são considerados nessas comunidades de menor valor quando comparados com ruminantes, os cônjuges das mulheres estão menos interessados em intervir com o controle feminino sobre aqueles meios de produção, viabilizando-se assim o livre manejo desses recursos por parte da mulher. Evidencia-se a alta importância do trabalho feminino no funcionamento das UPAFs em cinco dessas comunidades (menos Tiassol) situadas no semiárido da Região Nordeste do Brasil.

It is analyzed women micro-economic participation of six different agricultural communities in the City of Tauá, Inhamuns Semiarid Microregion, Ceará State, Brazil (Communities of Junco, Tapera, Lustal I, Lustal II, Tiassol and Queimadas), in relation to the rural tasks management. The Family Farm Production Units (FPUs) of these rural women represent 75.66% of the participants (n= 103) of the project. The total number of FPUs in the 6 communities studied is 305, therefore, the current study encompassed 24.59% of rural women in these communities. The in situ collected data through questionnaires, have been submitted to the frequency, multifactorial and variance statistical analyses. The rural women of these communities are predominantly 45.52 years old with school age children and they do not possess formal education. The partners of women are less interested in interfering in female control of these means of production because they are considered to be of less value in comparison to roçado and ruminant management. Thus, the women can freely manage these resources for family needs. They appear as main responsible for the fowl, swines and vegetables garden-orchard and are minimaly involved in activities with cultivation and ruminant cattle. From these results the importance of female work is clear for the functioning of the family farm production units in five rural communities (with the exception of Tiassol) being studied in the semiarid region in the Northeast of Brazil.

Typological diversity of feminine rural work in the Brazilian semi-arid

Objetivou-se caracterizar a diversidade do trabalho feminino no manejo agropecuário de unidades produtivas em comunidades rurais situadas no Semi-Árido brasileiro para melhor compreender o papel da mulher na formação da riqueza rural. Foi elaborada uma tipologia com 75 mulheres residentes em seis comunidades rurais semiáridas do Distrito do Baixo Trici, Ceará, Brasil, baseada na incidência do trabalho feminino no manejo rural associado ou não a outro trabalho familiar ou assalariado. Sete grupos de mulheres foram obtidos através da análise cluster, refletindo a diversidade do trabalho agropecuário feminino nessas comunidades rurais desfavorecidas, particularmente na alocação predominante da força de trabalho da mulher para produção de carne e ovos de aves e carne de suínos, hortícolas e frutas e em trabalhos administrativos da unidade familiar de produção rural.

To better understand the role of women in the agricultural wealth composition, this study aimed to characterize the feminine work diversity in the productive units farming management situated in Brazilian semi-arid rural communities. For such, a typology with 75 resident women in six rural communities of the Baixo Trici District, Ceará State, Brazil was performed. This typology was based on the feminine work incidence associated or not to another familiar or wage-earning work. Seven groups of women had been gotten through the cluster analysis, and they had reflected the feminine farming work diversity in these disfavored rural communities, particularly in the predominant allocation of the women work force for fowl and swine meat and fowl eggs, vegetables gardenorchad and in familiar unit administrative works.

Enzyme activities of tadpoles of bullfrogs fed diets containing different levels of crude protein

Este estudo objetivou determinar a atividades das enzimas digestivas de girinos de rã-touro, alimentados com diferentes rações durante 55 dias, na densidade de um girino por litro, em caixas com 30 l de água em condições laboratoriais. Aos 18 dias os níveis de proteína influenciaram a atividade da amilase de forma quadrática até o valor estimado 32% PB. A mesma tendência foi observada para a atividade específica da amilase que influenciou até o nível de 28% de PB e da atividade da tripsina que influenciou até o nível de 29% de PB. Não foi observada diferença significativa para lípase e atividade específica da lípase. Aos 26 dias a atividade enzimática da amilase e atividade específica da amilase e da Tripsina diminuiu com aumento da porcentagem de proteína. A enzima lipase atividade específica da lípase aumentaram de forma linear ao aumento dos níveis de proteína. Aos 35 dias de experimento a atividade da amilase foi estatisticamente significativa para o tratamento com 28% de PB. A atividade específica da amilase e a atividade da tripsina diminuíram com aumento da proteína na ração. Já a atividade da lípase aos 35 e 55 dias de experimento aumentou significativamente com aumento da proteína na ração. Aos 55 dias de experimento o aumento da proteína na ração influenciou de forma linear a atividade da tripsina. A atividade da lipase e atividade específica da lipase aumentaram com a elevação do nível de proteína bruta na ração.

This study was aimed to determine the digestive enzyme activity in bullfrog tadpoles, fed with commercial ration during 55 days, at the density of one tadpole per liter in 30 l boxes. After 18 days the levels of protein influenced the activity of amylase quadratically to the estimated 32% CP. The same trend was observed for the specific activity of amylase influenced by the level of 28% crude protein and the activity of trypsin that influenced by the level of 29% CP. There was no significant difference in lipase activity and specific lipase. At 26 days of the amylase enzyme activity and specific activity of amylase and trypsin decreased with increasing the percentage of protein. The enzyme lipase and lipase specific activity increased linearly to increased levels of protein. At 35 days of experiment amylase activity was statistically significant for treatment with 28% CP. The specific activity of amylase and trypsin activity decreased with increased protein in the diet. The activity of lipase at 35 and 55 days of the experiment increased significantly with increased protein in the diet. At 55 days of the experiment increased protein in the diet influenced in a linear activity of trypsin. The lipase activity and specific activity of lipase increased with increasing levels of dietary crude protein.

Origin of Cuban Creole cattle inferred by patri- and matrilineages

Cattle was absent from America before the discovery. Initially, bovine were brought to Greater Antilles (La Española, Puerto Rico, Jamaica and Cuba islands), and in the course of a few years, they were taken from Caribbean islands to the rest of Latin America. Nowadays, Cuban Creole cattle population is about 1300 heads, mainly located in the eastern region of the island. With the aim of analyzing the maternal origin of Cuban Creole cattle and detect possible contemporaneous, male mediated, gene flow, a 240 pb fragment of mitochondrial D-loop (mtDNA) and five microsatellites of Y chromosome (BTY) were studied in 36 dams and 21 sires, respectively. Genetic diversity was evaluated through number of haplotypes, mean number of pairwise differences and nucleotide diversity. The phylogenetic analysis was performed using a median joining. A total of 15 mtDNA haplotypes were detected in the studied population (10 from the European haplogroup T3, 3 from the African T1, 1 from the Nearern East T2, and 1 ambiguous T1-T3). The number of polymorphic sites, the mean nucleotide diversity, and the mean number of pairwise differences were 23, 0.014 and 3.36, respectively. Two patrilinages were detected, both belonging to the Y3 Zebu haplogroup. In conclusion, Cuban Creole cattle population had a mtDNA haplotypic composition similar to the observed in Creole and Mediterranean breeds, what is in concordance with its historical origin. Y chromosome analysis evidenced a male mediated process of zebu introgression.

Antes de descubrimiento, no existían bovinos en América. Los primeros, fueron introducidos en la Antillas Mayores (La Española, Puerto Rico, Jamaica y Cuba), y desde allí trasladados al resto de Latinoamérica. Actualmente, existen en Cuba alrededor de 1300 bovinos Criollos, concentrados principalmente en la región oriental. Con el objetivo de analizar el origen materno de esta raza y detectar eventos contemporáneos de flujo génico por vía paterna, se analizó un fragmento de 240 pb del D-loop mitocondrial (mtADN) y 5 microsatélites del cromosoma Y (BTY), en 36 hembras y 21 machos respectivamente. La diversidad genética se estimó mediante el número de haplotipos, el número de sitios polimórficos, el número de diferencias nucleotídicas entre pares de secuencias y el índice de diversidad nucleotídica, mientras que el análisis filogenético se realizó utilizando el método de median joining network. Dicho análisis permitió detectar 15 haplotipos mitocondriales (10 del haplogrupo europeo T3, 3 del africano T1, 1 del cercano oriente T2 y 1 ambiguo T1-T3) y 3 haplotipos en el BTY, ambos del haplogrupo cebuíno Y3. En el mtADN se detectaron 23 sitios polimórficos con una diversidad nucleotídica de 0,014 y 3,36 diferencias medias entre pares de secuencias. En conclusión, la población de bovinos Criollos Cubanos presentó una composición haplotípica mitocondrial comparable a la de otras razas criollas y mediterráneas, hecho que concuerda con su origen histórico. El BTY evidenció altos niveles de introgresion paterna de genes del zebú.

Hip height, milk production and reproductive performance in dairy cows raised under grazing

El objetivo del presente trabajo fue caracterizar las relaciones entre la altura a la cadera como indicador de tamaño corporal, con diferentes indicadores productivos y reproductivos en vacas lecheras mantenidas sobre pasturas en un intento por identificar biotipos con diferente aptitud en este tipo de sistemas. Se compararon vacas Holstein de tercera lactancia, de distinto tamaño corporal, que conviven en sistemas a pastoreo. Se analizaron variables productivas y reproductivas para los distintos tamaños. No se observaron diferencias estadísticamente significativas (p>0,05) entre las vacas de mayor tamaño y las de menor tamaño en las variables reproductivas y en los indicadores productivos estudiados. Los resultados indican que la altura no incide en los niveles productivos ni en los reproductivos. Se identificaron cuatro biotipos y se constata que para el sistema de producción de leche en la región de la pampa húmeda de la República Argentina, el más eficiente es el de vacas con menor altura y producción de leche media.

The aim of this study was to characterize the relationships between hip height as an indicator of body size, with different productive and reproductive indicators in dairy cows kept on pasture; in an attempt to identify biotypes with different aptitudes in this type of system. A comparison of productive and reproductive variables was made among Holstein cows of the third lactation, of different body sizes, which coexist in grazing systems. There were no statistically significant differences (p>0.05) among larger and smaller cows neither in reproductive traits nor in their productive performance. Four biotypes were identified. For the typical pampa dairy production grazing system the most efficient biotype is that of lower height and average milk production.

Phosphorus fertilization and arbuscular mycorrhizal inoculation in culture of mixed forages

Objetivou-se avaliar, em casa de vegetação, a resposta do cultivo consorciado entre o capimAndropogon e o estilosantes à inoculação com fungos micorrízicos arbusculares e aplicação de doses de fósforo em solo não esterilizado (condições naturais). Foi utilizado um Latossolo Amarelo Distrófico típico. O delineamento experimental foi em blocos casualizados, num esquema fatorial 4 x 3, sendo quatro doses de P (0, 60, 120 e 240 mg dm-3 de solo) e três tratamentos microbiológicos (controle; inoculação com o fungo Glomus clarum e inoculação com o inóculo nativo), com 3 repetições. Realizou-se dois cortes da parte aérea, a cada 60 dias. Analisou-se a produção de matéria seca da parte aérea e raiz, os acúmulos de proteína bruta, P, K, Ca, Mg e S; porcentagem de colonização micorrízica em ambas as plantas e densidade de esporos. Os resultados demonstraram que o aumento das doses de P incrementaram significativamente as variáveis estudadas. Esses resultados foram evidenciados com a inoculação micorrízica, com destaque para a presença da espécie Glomus clarum, principalmente para o primeiro corte. A participação da leguminosa na matéria seca total do consórcio foi aumentada pela inoculação micorrízica nas menores doses de P. A colonização micorrízica e a densidade de esporos não foram influenciadas pelos tratamentos microbiológicos.

This work, carried out under greenhouse, had for objective to evaluate the response of the intercropped Stylosanthes and Andropogon grass to arbuscular mycorrhizal inoculation and levels of phosphorus in soil no sterilized (natural conditions). A randomized blocks design was used in a 4 x 3 factorial scheme (four phosphorus levels: 0, 60, 120 and 240 mg dm-3 of soil) and three microbiology treatments (control; inoculation with Glomus clarum and inoculation with native inoculum) with three repetitions. Were accomplished two cuts of the aerial part, each 60 days. It was analyzed the production of dry matter of the aerial part and root, the accumulations of crude protein, P, K, Ca, Mg, and S, percentage of mycorrhizal colonization in both plants and density of spores. The results demonstrated that the increase of the doses of P increased significantly the studied variables. Those results were evidenced with the arbuscular mycorrhizal inoculation, specially for the species Glomus clarum, mainly for the first cut. The participation of the legume in the dry matter total of the mixture was increased by the arbuscular mycorrhizal inoculation in the smallest levels of P. The mycorrhizal colonization and the density of spores were not affected by the microbiology treatments.

**Performance of Carassius auratus with different food strategies in water recirculation system**

The efficiency of a recirculation system for the cultivation of C. auratus, fed with natural and artificial diets was evaluated. The experiment consisted of four treatments with four replicates. The first two treatments used recirculation system and the last two static system. In the first and fourth treatment, animals were fed with brine shrimp biomass (50% CP), while in the second and third treatments a commercial flake ration (42% CP) was used. At the end of cultivation (60 days), water samples were taken from all experimental units and subjected to standard plate count for determining the density of mesophilic bacteria. Final weight (g), final length (cm), specific growth rate (% day -1) and weight gain (%) were significantly different (p<0.05) among tested diets, but the culture systems did not affect fish performance. There was significant difference (p<0.05) between systems for total ammonia and nitrite. Animals fed with brine shrimp biomass acquired more intense and brighter colors than those fed only with commercial flake food. The values of standard plate count of mesophilic bacteria ranged from 7.0 × 10³ to 1.1 × 10(4) CFU.ml-1. In this study we observed that C. auratus is a species tolerant to adverse water conditions, perhaps with increased stock densities, the recirculation system could play some positive role on the zootechnical performance of cultured animals.

A eficiência de um sistema de recirculação para o cultivo de C. auratus, alimentados com dieta natural e artificial foi avaliada. O experimento consistiu de quatro tratamentos com quatro repetições. Os dois primeiros tratamentos utilizaram sistemas de recirculação e os dois últimos sistemas estáticos. No primeiro e quarto tratamento, os animais foram alimentados com biomassa de artêmia (PB 50%), enquanto nos tratamentos dois e três, com ração comercial em flocos (42% PB). Ao final do cultivo (60 dias), amostras de água foram coletadas em todas as unidades experimentais e submetidos a contagem padrão em placas para determinação da densidade de bactérias mesófilas. O peso final (g), comprimento final (cm), taxa de crescimento específico (% dia-1) e ganho de peso (%) foram significativamente diferentes (p<0,05) entre as dietas testadas, mas os sistemas de cultivo não afetaram o desempenho dos peixes. Houve diferença significativa (p<0,05) entre os sistemas para os níveis de amônia total e nitrito. Os animais alimentados com biomassa artêmia adquiriram cor e brilho mais intensos do que aqueles alimentados apenas com ração comercial em flocos. Os valores de contagem padrão em placas de bactérias mesófilas variaram de 7,0 × 10³ para 1,1 × 10(4) CFU.ml-1. Neste estudo, observou-se que C. auratus é uma espécie tolerante a condições adversas de água, talvez com maior densidade de estocagem, o sistema de recirculação poderia desempenhar papel positivo sobre o desempenho zootécnico dos animais cultivados.

**Genetic diversity of brazilian buffaloes (Bubalus bubalis) using DNA microsatellites**

Genetic diversity of Brazilian buffaloes is studied using a panel of twenty-five DNA microsatellite markers (CSSM41, CSSM8, CSRM60, CSSM33, BM1818, HEL13, MAF65, CSSME70, HSC,BRN, CSSM36, CSSM22, HAUT24, BM1824, SRCRSP8, TGLA227, ILSTS33, INRA23, BM8125, CSSM19, INRA37, CSSM66, ILSTS011, OarFCB48, SPS115). Forty samples randomly chosen from each of the Brazilian Buffaloes populations (Carabao, Jafarabadi, Mediterraneo, Murrah and Baio) were analyzed. Anyway the homogeneity test between observed and expected heterozygosity and the results of the Hardy-Weinberg equilibrium pointed out the stability of Baio and Carabao populations. Genetic distances, factorial analysis and individual assignation values showed that Baio, Mediterraneo and Murrah form a common genetic cluster as shown by their high genetic similarity in spite of their morphological divergence. That Carabao is a member of a different subspecies is confirmed. These findings demonstrate the success of Brazilian Baio and Carabao conservation efforts, and point to the need to develop new strategies of conservation for the remaining Brazilian buffalo populations.

Foi estudada a diversidade genética de búfalos do Brasil utilizando-se vinte e cinco marcadores microssatélites (CSSM41, CSSM8, CSRM60, CSSM33, BM1818, HEL13, MAF65, CSSME70, HSC, BRN, CSSM36, CSSM22, HAUT24, BM1824, SRCRSP8, TGLA227, ILSTS33, INRA23, BM8125, CSSM19, INRA37, CSSM66, ILSTS011, OarFCB48, SPS115). Foram analisadas amostras colhidas ao acaso de cinco populações, ou seja, raças Carabao, Jafarabadi, Mediterrâneo e Murrah, mais o tipo Baio. Em geral, os valores para a diferença entre as heterozigosidades (Ho - He) foram bastantes pequenas, significando equilíbrio nos marcadores utilizados para este tipo de estudo. Os valores do GST demonstraram um nível alto de diferenciação genética e os da estatística F: Fis (f), Fst (q) e Fit (F) demonstraram que os marcadores utilizados permitem inferir informações adequadas sobre as populações, podendo-se deduzir que os grupos Baio, Carabao, Jafarabadi e Mediterrâneo apresentam-se mais homogêneos que o grupo Murrah, o qual mostra níveis altos de endogamia. Os resultados dos estudos de distância genética mostraram que as populações de Baio, Mediterraneo e Murrah, agrupando-se em um cluster comum, demonstra alta similaridade genética, não obstante as suas divergências fenotípicas, confirmando que o grupo Carabao constitui uma diferente subespécie. Os resultados, principalmente das populações de Baio e Carabao, mostram o êxito do trabalho de con-servação genética e a necessidade de se desenvolver novas estratégias para a conservação do germoplasma dos búfalos do Brasil.

Fermentation and nutritive value of elephant grass silage inoculated with Streptococcus bovis

O experimento foi desenvolvido objetivando-se avaliar o efeito da inoculação de estirpes de Streptococcus bovis (HC5 e JB1) sobre o pH, a produção de amônia e o valor nutricional em silagens de capim-elefante (Pennisetum purpureum Schum). O delineamento experimental foi o inteiramente casualizado, com três tratamentos: T1 - capim-elefante, T2 - capimelefante inoculado com Streptococcus bovis HC5 e T3 - capim-elefante inoculado com Streptococcus bovis JB1, utilizando cinco repetições por tratamento. A menor concentração de amônia foi observada na silagem tratada com inoculante à base Streptococcus bovis JB1 (5,90 p.100 N-total). A inoculação aumentou os teores de ácido láctico e diminuiu os teores de ácidos acético, butírico e propiônico, sendo que as silagens inoculada com Streptococcus bovis JB1 e HC5 foram os que apresentaram os maiores valores de ácido láctico. Não houve diferença estatística para os teores de MS e PB. Para os valores das fibras, a silagem de capim-elefante inoculada com Streptococcus bovis JB1 apresentou o menor valor de FDN (59,77 p.100) e HEM (26,71 p.100). O maior valor da DIVMS foi observado na silagem com Streptococcus bovis JB1, mostrando superioridade de quatro pontos percentuais (64,23 p.100) em relação ao tratamento sem inoculante bacteriano (60,35 p.100). O uso Streptococcus bovis JB1 melhora o processo fermentativo além de promover melhorarias na qualidade da fibra e na DIVMS da silagem estudada.

The experiment was developed to evaluate the effect of strains of Streptococcus bovis (HC5 and JB1) on pH, ammonia production and nutritional value in elephant-grass silages (Pennisetum purpureum Schum). The experimental design was entirely randomized, with three treatments: T1 elephant- grass, T2 - grass-elephant inoculated with Streptococcus bovis HC5, T3 - elephant grass inoculated with Streptococcus bovis JB1, totaling five replicates per treatment. The smallest value of ammonia was observed in the silage treated with inoculante the base Streptococcus bovis JB1 (5.90% N-total). Inoculation increased the levels of lactic acid and decreased levels of acetic, propionic and butyric acids, and the silages inoculated with Streptococcus bovis JB1 and HC5 were those with the highest values of lactic acid. There were not statistical differences for the tenors of dry matter (MS) and crude protein (PB). For the values of the fibers, the grass-elephant silage inoculated with Streptococcus bovis JB1, it presented the smallest value of neutral detergent fiber (59.77 %) and Hemicellulose (26.71 %). The largest value of in vitro dry matter digestibility (DIVMS) was observed in the silage with Streptococcus bovis JB1, showing superiority of four percentile points (64.23 %) in relation to the treatment without bacterial inoculante (60.35 %). The use Streptococcus bovis JB1 was efficient in the process fermentativo besides promoting would get better in the quality of the fiber and DIVMS in the studied silage.

Efficiency of feed supplementation for nile tilapia using exponential growth model

Objetivou-se avaliar a aplicabilidade do modelo de crescimento exponencial no estudo da eficiência da suplementação alimentar com mananoligossacarídeo e β-glucano para tilápias do Nilo criadas em tanques-rede. O experimento foi realizado em piscicultura de criação de tilápias em tanques-rede. Tilápias jovens, com peso inicial de 25,4 ± 2,04 g, foram distribuídas em 12 tanquesrede de 2 x 2 x 1,5 m, com volume útil de 6 m³ e densidade de 2500 peixes por tanque. Para estudo realizou-se a biometria individual de uma amostra aleatória de 5% dos peixes de cada unidade experimental. Os resultados permitem concluir que a adição de suplemento até o nível de 2000 mg/ kg de ração não altera a taxa de crescimento. O modelo exponencial pode ser usado para comparar a eficiência de diferentes dietas.

The aim of this study was to evaluate the applicability of the exponential growth model to study feed supplementation efficiency with mannan oligosaccharide and β-glucan in Nile tilapia raised in net cages. The trial was carried out in a cage fish farm. Tilapia juveniles (initial weigh 25.4 ± 2.04 g) were distributed in 12 cages (2 x 2 x 1.5 m), with 6 m³ volume and stock density of 2500 fish per cage. To evaluate the exponential growth model, a randomized sample of 5% fish was collected for individual biometry in each experimental unit. The results show that none of supplement levels increased the growth ratio of Nile tilapias and the exponential growth model can be used to compare efficiency of different diets.

Feeding frequency and night lighting and feedlot heifers performance during summer

Se determinó el efecto combinado de aumentar la frecuencia de alimentación e iluminación nocturna durante el verano en la respuesta productiva y características de la canal de 171 vaquillas de razas de carne. Los tratamientos fueron: dos raciones diarias (testigo) y tres raciones diarias más la iluminación del comedero de 12:00 a 02:00 h (tratado), durante 84 días. Las vaquillas recibieron las mismas dietas. Las vaquillas tratadas pesaron 16 kg más (p<0,05), tuvieron mayor ganancia diaria (0,140 kg d-1; p<0,05), y menor conversión alimenticia (7,69 vs. 8,69 kg; p<0,10) que el grupo testigo, pero el consumo de alimento no fue diferente. Las vaquillas testigo mostraron mayor (p<0,05) frecuencia respiratoria que las tratadas (93,5 vs. 83,9 resp min-1), lo que sugiere un mayor grado de estrés calórico en esos animales. El peso de la canal caliente fue mayor (p<0,05) en las vaquillas tratadas que en las testigo (244,3 vs. 233,9 kg), pero no hubo diferencias en otras características de la canal. Los resultados sugieren que el aumentar la frecuencia de alimentación y el fotoperiodo en verano pueden mejorar las respuestas productivas y la adaptación a temperaturas altas en vaquillas engordadas en corral.

The combined effect of increasing feeding frequency and night lighting on feedlot performance and carcass traits during summer was studied in 171 beef heifers. Treatments were: two rations daily (control group) and three rations daily (treated group), during a feedlot period of 84 days. Heifers received the same diets. Treated heifers were 16 kg heavier (p<0.05), had higher daily gain (0.140 kg d-1; p<0.05), and better feed conversion (7.69 vs. 8.69 dg d-1; p<0.05) than control heifers, although feed intake was similar. Control heifers showed higher (p<0.05) respiration rate than treated (93.5 vs. 83.9 breaths min-1), which suggests higher level of heat stress in those animals. Hot carcass weight was higher (p<0.05) in treated heifers than in control (244.3 vs. 233.9 kg); however, there were no differences in the other carcass traits. These results suggest that increasing feeding frequency and photoperiod during summer may improve feedlot performance and adaptation to high temperatures in beef heifers.

**Osmolarity of activator and dilution rate in the activation of cryopreserved semen of curimba (Prochilodus lineatus)**

Objetivou-se avaliar a influência de ativadores com diferentes osmolaridades e taxa de diluição na ativação de sêmen criopreservado de curimba (Prochilodus lineatus). Foram utilizados quatro reprodutores machos capturados na Estação de Piscicultura da CEMIG, Itutinga, MG. As amostras de sêmen foram diluídas em duas soluções (DMSO + lactose e metanol + lactose) na proporção de 1:4 e congeladas. Foram avaliadas as taxas (%) e duração (s) da motilidade espermática dos tratamentos. Na ativação foram utilizados ativadores contendo as respectivas osmolaridades: 30, 99, 183 e 293 mOsm nas taxas de diluição de 1:2, 1:4, 1:6, 1:8 sêmen: ativador. A taxa de diluição 1:2 e 1:8 foram estatisticamente significativas para duração da motilidade para o sêmen criopreservado com DMSO. Para a diluição 1:2, o sêmen ativado com o ativador contendo 30 mOsm, apresentou duração de motilidade maior em relação ao sêmen ativado com ativadores com 183 e 293 mOsm. No entanto, para a utilização do ativador com 30 mOsm, se obteve maior duração da motilidade na diluição de 1:2 em relação a diluição de 1:4. Na taxa de diluição 1:6, quando o sêmen foi ativado com o ativador de 30 mOsm, a taxa de motilidade foi superior à apresentada pelo sêmen que foi ativado com 293 mOsm. Na taxa de diluição de 1:8, o uso de ativador contendo 99 mOsm apresentou maior duração de motilidade em relação ao uso do ativador com 293 mOsm. Ativadores contendo altas osmolaridades podem proporcionar menores taxas e duração da motilidade em sêmen de curimba (Prochilodus lineatus) criopreservado com os crioprotetores metanol ou DMSO.

The objective of this work was to evaluate the influence of activators with different osmolarities and dilution rate in the activation of cryopreserved semen of curimba (Prochilodus lineatus). We used four breeding males captured in the Fishfarming Station of CEMIG, Itutinga, MG. Semen samples were diluted in two solutions (DMSO + methanol and lactose + lactose) at 1:4 ratio and frozen. The rates (%) and duration (s) of sperm motility for treatments were assessed. Activators with respective osmolarities: 30, 99, 183 and 293 mOsm at dilution rates of 1:2, 1:4, 1:6, 1:8 (semen: activator) were used. The dilution rates of 1:2 and 1:8 influenced duration of motility in semen cryopreserved with DMSO. For the 1:2 dilution, the semen activated with the activator containing 30 mOsm, presented greater motility duration than semen activated with activators with 183 and 293 mOsm. However, for the activator with 30 mOsm, it was obtained longer motility duration at a dilution of 1:2 compared to 1:4 dilution. At 1:6 dilution rate, when the semen was activated with the activator 30 mOsm, the motility rate was higher than that provided by the semen that was activated with 293 mOsm. At the dilution rate of 1:8, the use of activator containing 99 mOsm showed longer motility duration in relation to use of the activator with 293 mOsm. Activators containing high osmolarities can provide lower rates and duration of motility in semen of curimba (Prochilodus lineatus) cryopreserved with cryoprotectants methanol or DMSO.

**Tambaqui (Colossoma macropomum) semen characteristics on equatorial latitude**

O tambaqui Colossoma macropomum (Cuvier, 1818) é uma espécie de teleósteo da bacia amazônica e abundante naquela região, de alto valor comercial e forte apelo culinário e esportivo sendo uma das principais espécies amazônicas com larga distribuição nos rios e nas áreas próximas a Manaus (Silva et al., 1984) Este trabalho teve por objetivo avaliar as características espermáticas do sêmen de tambaqui com e sem indução hormonal por um período de doze meses. Utilizou-se 26 machos com idade média de três anos, pertencentes ao Centro de Pesquisas em Aquicultura (CPAq) do Departamento Nacional de Obras Contra às Secas (DNOCS), devidamente identificados com chips magnéticos. Os animais foram divididos em dois grupos: induzidos (I) e não induzidos (NI). Os animais do grupo I receberam 2 mg de extrato de pituitária de carpa (EPC-1) por kg de peso vivo (PV), via intra celomática. O sêmen foi coletado após 14 horas através de massagem abdominal. Os parâmetros avaliados foram: volume, pH, osmolaridade e concentração espermática. Os peixes apresentaram peso médio de 5410 g, comprimento total de 68 cm e comprimento padrão de 59,17 cm. Para os grupos I e NI foram observados respectivamente: volume médio de 5,05 mL e 0,55 mL (p<0,05); pH médio de 8,21 e 8,09; osmolaridade média de 320,51 e 323 mOsm/kg e concentração espermática média de 22,93 x 10(9) e 40,46 x 10(9) sptz/mL (p<0,05). A produção espermática total foi de 115,79 x 10(9) sptz/mL no grupo I sendo de 22,25 x 109sptz/mL no grupo NI. Não houve diferença significativa entre os valores obtidos de osmolaridade e pH dos indivíduos induzidos e não induzidos. No entanto, a concentração espermática e o volume no grupo induzido apresentaram valores significativamente superiores (p<0,05) comparado aos indivíduos não induzidos.

The Amazonian fish known as tambaqui (Colossoma macropomum Cuvier, 1818) is a osseous fish and has high commercial value because of its meat quality and for recreational fishing. Tambaqui is one of the major species in the Amazon basin and found in most rivers and surroundings of Manaus city (Silva et al., 1984). The present study was carried out to evaluate sperm parameters from tambaqui, subjected or not to hormone treatment for a period of 12 months. We used 26 males with three years of age, raised at the Aquaculture Research Center of the National Department for Drought Control (DNOCS). Animals were identified with magnetic chips and divided into two groups: controls (NI) and hormone-treated (I), which received 2 mg of carp pituitary extract (CPEkg-1) of body weight (via intra celomic). Semen was collected 14 hours after hormonal induction and the following parameters evaluated: volume, pH, osmolarity and sperm concentration. Fishes had body weight of 5410 g, with total length and standard length of 68 cm and 59.17 cm, respectively. In the case of hormone-treated and control animals, we found the following criteria, respectively: semen volume of 5.05 mL and 0.55 mL (p<0.05); pH of 8.21 and 8.09; osmolarity of 320.51 and 323 mOsm/kg; sperm concentration of 22.93 x 10(9) and 40.46 x 10(9) sptz/mL (p<0,05). Total sperm productions were quantified as 115.79 x 10(9) sperm/mL in treated fishes and 22.25 x 10(9) sperm/mL in the controls. We conclude that treatment of adult tambaqui with carp pituitary extract increase semen volume but reduces sperm concentration while had no effect on sperm osmolarity and pH.

**Prediction of protein fractioning of Brachiaria brizantha cv Marandu through Artificial Neural Networks**

Este artigo tem como objetivo relacionar variáveis morfogenéticas da forragem e dados climáticos com as frações de proteínas (A, B1, B2, B3 e C), através da rede neural aritifical conhecida como Multi-Layer Perceptron, com três camadas e algoritmo de treinamento baseado na retropropagação do gradiente do erro, a fim de criar um modelo capaz de predizer as frações protéicas de forragens a partir de suas características morfogenéticas e climáticas. Os dados utilizados para o treinamento e teste da rede foram coletados em um experimento que foi realizado em uma área experimental de 25,2 ha, com coordenadas 47º 26' W, 21º 59' S, formada com capim braquiarão, em um delineamento em blocos completos e casualizados, com 4 repetições e uma oferta de forragem de 5% (5 kg de massa seca por 100 kg de peso animal.dia-1). Cada bloco foi dividido em quatro unidades experimentais de 1,575 ha, com cinco piquetes de 0,315 ha cada. As amostras foram colhidas dois dias antes da entrada dos animais, sendo a análise das frações de proteínas realizadas em laboratório para posteriormente serem comparadas com os valores estimados pela rede. Assim, através da comparação entre os dados de saída da rede e os obtidos pela análise laboratorial foi possível calcular o erro médio para as frações A, B1, B2, B3 e C de proteínas e com isso, pode-se concluir que o modelo MLP é capaz de predizer com eficiência as frações de proteínas de Brachiaria brizantha.

This paper aims to connect morphogenetic variables of forage and climatic data, with protein fractions (A, B1, B2, B3 and C) through the artificial neural networks known as Multi-Layer Perceptron, with three layers and algorithm training based on back-propagation of error gradient, in order to create a model to predict the protein fractions of fodder from their morphogenetic characteristics and climate. The data used for training and the test were collected in an experiment that was conducted on a 25.2 ha experimental area, located at 47º26'W, 21º59'S, and with pasture composed of Brachiaria brizantha cv Marandu, in a completely randomized block, with four replicates and a forage allowance of 5% (5 kg of dry matter per 100 kg animal.day-1). Each block was divided into four experimental units of 1.575 ha, with five paddocks of 0.315 ha each. Samples were taken two days before the entry of animals, protein was analysed at laboratory to subsequently be compared with the values estimated by the network. Thus, by comparing the output of the network and those obtained by laboratory analysis, it was possible to calculate the average error for fractions A, B1, B2, B3 and C proteins and, thus, can be concluded that the model MLP is able to efficiently predict protein fractions of Brachiaria brizantha.

Characteristics of production of buffel grass as function of cutting intensity and frequency

Objetivou-se avaliar características morfogênicas, estruturais e a produção de biomassa do capim-buffel sob intensidades e freqüências de corte. Utilizou-se um pasto já implantado de capimbuffel, cultivar Molopo. A área total utilizada foi dividida em 20 parcelas de 8 m² cada com linha de bordadura de 1 m entre as parcelas. Foi utilizado um esquema de parcelas subdivididas no tempo, tendo nas parcelas um arranjo fatorial 2x2 referente a combinações entre duas alturas de corte (60 e 80 cm) e duas alturas de resíduo (20 e 40 cm), em delineamento experimental de blocos completos ao acaso, com cinco repetições, totalizando 20 unidades experimentais, que receberam as denominações 20-60, 20-80, 40-60, 40-80. Houve efeito (p<0,05) dos tratamentos para a produção de matéria seca por corte, sendo que os tratamentos 20-80 e 40-80 resultaram em maiores produções. O perfilhamento, relação lâmina/colmo, número de folhas vivas por perfilho e diâmetro de touceira, foram influenciados (p<0,05) pelas diferentes formas de manejar o pasto de capimbuffel. A taxa de aparecimento de folhas e o filocrono não diferiram (p>0,05), entre os tratamentos. A freqüência e a intensidade de corte influenciaram o perfilhamento, relação lâmina/colmo e a produção de matéria seca do capim-buffel tanto para o corte como para a produção total.

The objective of this experiment was to evaluate morphogenetic and structural characteristics and biomass production of buffel grass as a function of cut intensities and frequencies. A previously established pasture of buffel grass cultivar Molopo was used. Total area was splited in twenty 8 m² experimental unities with 1 m border lines. A split plot scheme was used with plot in factorial scheme 2x2 to combination of two height of cut (60 and 80 cm) and two height post cut (20 and 40 cm). The experimental design was entirely randomized blocks, with five replicates named 2060, 20-80, 40-60, 40-80. There (p<0.05) of treatments for dry matter per cut production and higher values were observed to 20-80 and 40-80. Tillering, leaf/steam ratio, number of alive leafs per tiller and diameter of plant were influenced by (p<0.05) by different management of buffel grass. Leaf appearance ratio and phylocron were not different (p>0.05) between treatments. Cutting frequency and intensities influenced tillering, leaf/ stem ratio and dry matter production for both the cut as to the total.

Morphostructural variability of Blackbelly sheep in Campeche, Mexico

Con el propósito de estudiar la conformación corporal de ovinos Blackbelly, se tomó una muestra aleatoria de 220 hembras y 36 machos de los rebaños del municipio de Campeche, México. La zoometría fue la base del estudio y se evaluó con 14 medidas corporales y el peso vivo de ovinos de uno, dos y tres años de edad. Se efectuaron análisis de varianza y de correlación, así como un análisis de conglomerados en los machos y hembras de uno y tres años de edad. Las medidas corporales tuvieron cambios significativos (p<0,05) hasta los tres años edad. Las diferencias entre hembras y machos fueron más grandes después de un año de edad, sobre todo en el peso vivo. Todas las mediciones se correlacionaron significativamente (p<0,01), particularmente el peso vivo con el perímetro torácico, con la altura a la cruz, y con el perímetro testicular. Los animales de un año de edad mostraron una variabilidad corporal considerable; una parte de ellos tenía valores zoométricos muy cercanos a los límites máximos estimados en el grupo de tres años de edad. Por sus patrones corporales en la etapa adulta, los ovinos Blackbelly muestran una tendencia a ser animales productores de carne.

In order to study the body conformation of Blackbelly sheep, a random sample of 220 females and 36 males was taken in flocks of the municipality of Campeche, Mexico. Zoometry was the base of the study and it was evaluated with 14 body measurements and live weight of one, two and three years old sheep. Analysis of variance and correlation were performed, as well as a clustering test in ewes and rams one and three years old. Body measurements had significant (p<0.05) changes throughout three years of age. Differences between males and females were higher after one year of age, especially live weight. All measurements were significantly correlated (p<0.01), particularly live weight with thoracic perimeter, height at withers, and testicular perimeter. One year old animals had a considerable body variability; a portion of them had zoometric values very close to the maximum limits that were estimated in the three-year-old group. Based on their body patterns as adults, Blackbelly sheep show a tendency to be meat producer animals.

**Sanitary and nutritional characterization of honeybee colonies in Eucalyptus grandis plantations**

In Uruguay, many beekeepers transport their colonies to Eucalyptus grandis plantations at the end of the summer and autumn, obtaining important honey harvests. However, at the end of the flowering period the colonies become extremely weakened undergoing high levels of mortality. Nutritional and health problems could explain the weakening of colonies. In order to find out the causes for this weakening, colonies of the same size were taken to an E. grandis plantation, split up in three groups differentiated by the availability of pollen. Throughout the flowering period we registered: the botanical origins and crude protein content of the incoming pollen, the body protein of the bees, the infection by Nosema ceranae and the infestation of Varroa destructor, the brood area and the production of honey. The most important findings were: i) the sustained decline in botanical diversity of pollen as the flowering period of E. grandis advanced until only pollen from this species remained; ii) pollen from E. grandis presented crude protein values close to 30%, but these gradually diminished reaching values lower than 20% towards the end of the flowering period; iii) those colonies which initially counted on pollen reserves presented bees with higher body protein a few days after settling in the plantation and lower levels of infection with N. ceranae during most of the flowering period; iv) pollen availability did not affect levels of infection by V. destructor, size of the brood area or honey production. Bee's nutritional deficit during E. grandis flowering could generate adequate conditions for the multiplication of N. ceranae. At the end of the Eucalyptus' flowering period colonies presented on average more than 90% of foraging workers infected with N. ceranae and 12% infection of adult bees with V. destructor. Incidence of both pathogens in weakened bees could explain colony losses.

En Uruguay muchos apicultores trasladan sus colonias a las forestaciones de Eucalyptus grandis al final del verano y en otoño obteniendo importantes cosechas de miel. Sin embargo, cuando finaliza la floración las colonias se encuentran muy debilitadas, sobreviniendo una elevada mortalidad. Problemas nutricionales y sanitarios podrían explicar el debilitamiento de las colonias. Para averiguar las causas del debilitamiento se llevaron colonias de igual tamaño a una forestación de E. grandis, separadas en tres grupos diferenciados por la disponibilidad de polen. A lo largo del periodo de floración se registró: el origen botánico y el contenido de proteína cruda del polen que ingresaba en las colmenas, la proteína corporal de las abejas, la infección por Nosema ceranae y la infestación por Varroa destructor, el área de cría y la producción de miel. Los resultados más importantes hallados fueron: i) la sostenida disminución de la diversidad botánica del polen a medida que transcurría el periodo de floración de E. grandis hasta quedar únicamente el polen de esta especie; ii) el polen de E. grandis presentó valores de proteína bruta cercanos al 30%, pero fue disminuyendo paulatinamente hasta alcanzar un valor inferior a 20% al final de la floración; iii) las colonias que contaban inicialmente con reservas de polen presentaron abejas con mayor proteína corporal pocos días después de llegar a la forestación y menor infestación de N. ceranae durante la mayor parte del periodo de floración; iv) la disponibilidad de polen no incidió en la infestación de V. destructor, el área de cría y la producción de miel. El déficit nutricional de las abejas durante la floración de E. grandis podría generar las condiciones adecuadas para la multiplicación de N. ceranae. Al final de la floración del eucalipto las colonias presentaron promedialmente más del 90% de las abejas pecoreadoras infectadas con N. ceranae y 12% de V. destructor en las abejas adultas. La incidencia de ambos patógenos sobre las abejas debilitadas podría explicar la pérdida de colonias.

Dairy farming in the Asturias Region (Spain)

L'élevage bovin laitier représente près de la moitié de la marge brute agricole des Asturies, et plus du 10% du quota laitier de l'Espagne. Il s'est produit durant les trente dernières années, un rapide processus d'augmentation de taille des exploitations, d'intensification, de spécialisation et de concentration géographique, très marqué par une plus grande dépendance externe (alimentation, emprunts, amortissements, règlements, aides...) et par une moindre flexibilité face aux risques du marché (prix du lait, coûts des aliments et fournitures) et de la transmission des exploitations. Quelle continuité pour cette activité? Disparition, intensification au sein de sociétés ou solutions alternatives (filières de qualité, pluriactivité...)?

Dairy farming represents a half of the agrarian gross margin of Asturias, and more of 10% of the milk quota of Spain. During last thirty years it occurred a quick process of increasing size of farms, intensive rearing, specialization and geographical concentration, very marked by a bigger external dependency (feeding, borrowing, depreciations, regulations, subsidies) and by a lesser flexibility facing risks of the market (price of the milk, costs of food and supplies) and of farm transmission. What continuity for this activity? Disappearing, intensive rearing within societies or alternative solutions (based on quality sectors, part-time farming...)?

Integrity of membrane and sperm chromatin in bucks with and without scrotal bipartition

Se cree que el escroto bipartido de caprinos de regiones áridas y semiáridas mejora la calidad del semen al contribuir a la regulación térmica intratesticular. Se evaluó la calidad del semen y de los espermatozoides de cuatro machos cabríos con escroto entero y tres con escroto bipartido, por medio de análisis convencionales, membrana plasmática y cromatina de los espermatozoides. Los espermatozoides de animales con escroto bipartido presentan mejor calidad física y morfológica, lo cual sugiere mejor adaptación a climas áridos y semi-áridos.

Some bucks from arid and semi-arid regions have scrotal bipartition. It has been speculated that this feature improves semen quality by the regulation of intratesticular temperature. This work evaluated the quality of semen and spermatozoa of four bucks without, and three with scrotum bipartition, through conventional analyses, hypoosmotic swelling test and acridine orange. Results shows better physical and morphological characteristics in addiction better quality of plasma membrane for animals with scrotal bipartition, which suggests better adaptation to arid and semiarid regions in these animals.

Circadian variation in locomotor and feeding periods of two land snail species

The daily locomotor activities, feeding time and active periods of two snail species (Archachatina marginata and Achatina achatina) were investigated in an artificial habitat. Chemical analysis of the haemolymph were carried out for the 24 hours period. There were differences (p<0.05) in the activities of the 2 snail species. The mean distance traveled by A. marginata ranged between 1.9 cm to 32.6 cm while A. achatina ranged from 1.0 to 18.9 cm. The peak of the feeding activity was at 24.00 h for both species while the least, was recorded between 4:00 and 20.00 h. The two snail species were most active at 22:00-24:00 h and were least active at 11:00-17:00 h. The chemical analysis of the haemolymph showed difference (p<0.05) in the concentrations of Cl- and lipids across the 24 hours period.

Fueron investigadas la actividades diarias de locomoción, alimentación y periodos activos de dos especies de caracoles Archachatina marginata y Achatina achatina, en un hábitat artificial. Se realizaron análisis químicos de la hemolinfa durante un periodo de 24 horas. Se encontraron diferencias (p<0,05) entre las actividades de las dos especies. La distancia media recorrida por A. marginata osciló entre 1,9 y 32,6 cm, mientras que para A. achatina fue entre 1,0 y 18,9 cm. El máximo de la actividad alimenticia se registró a las 24:00 horas para ambas especies mientras que la actividad mínima se registró entre las 4:00 y las 20:00 horas. Las dos especies, estuvieron más activas entre las 22:00 y las 24:00 horas y la actividad fue mínima entre las 11:00 y las 17:00 horas. Hubo diferencias (p<0,05) en la concentración de Cl- y lípidos de la hemolinfa durante las 24 horas.

Pedigree analysis of the canine breed Cimarron Uruguayo

Para evaluar la variabilidad genética de la raza canina Cimarrón Uruguayo, se analizó la totalidad de la información genealógica disponible (n= 6079) utilizando el programa informático ENDOG v4.5. Los datos recabados sugieren sobrerepresentación de determinados reproductores y pérdida de genotipos fundacionales. La F media para la población de referencia viva apta para la reproducción fue de 0,03, la cual ha aumentado en generaciones recientes. La población ha tenido una evolución favorable en relación a crecimiento en número de individuos, aunque es muy heterogénea y requiere la aplicación de criterios en los cruzamientos que tiendan a minimizar el nivel de consanguinidad por generación.

In order to assess the genetic variability of the Cimarron Uruguayo dog breed, we analyzed all the available pedigree records (n= 6079) using ENDOG v4.5 software. The results suggest over representation of certain breeding animals and loss of founder genotypes. Mean F of the reference population, consisting of live breeding animals, was 0.03, which has increased in recent generations. The population has had a favourable evolution with regard to number of individuals, although it is very heterogeneous and requires the application of mating criteria tending to the minimization of inbreeding levels per generation.

In vitro maturation of bovine granulosa cells for steroid hormone production

This study aimed to evaluate the effects of preincubated granulosa cells on in vitro maturation and steroid hormones production in cows. Granulosa cells from the ovaries were cultured using the modified M-199 with Earle's salts. 1% bovine serum albumin was added and 5% fetal calf serum. Also 0.8% of antibiotics was also included. Cultures were incubated at 37ºC in a 95% air and 100% relative humidity. There were significant differences among values of progesterone and estradiol concentration obtained for levels of inclusion of FSH and LH. It can be concluded that there is necessity for supplementation of hormones in culture medium for bovine IVM.

Se evaluó el efecto de células de granulosa preincubadas sobre la maduración in vitro y producción de hormonas esteroides en vacas. Las células de granulosa de los ovarios fueron cultivadas empleando el M-199 modificado con sales de Earle. Se añadió 1% de albúmina de suero bovino y 5% de suero fetal de ternero. También se incluyó un 0,8% de antibióticos. Los cultivos fueron incubados a 37ºC con 95% de aire y 100% de humedad relativa. Se registraron diferencias significativas entre las concentraciones de progesterona y estradiol obtenidas con los niveles de inclsuión de FSH y LH. Puede concluirse que es necesario suplementar con hormonas el medio de cultivo para IVM en bovinos.

Rate of PGF₂_α -synchronized ovulation and follicular dynamics in criollo lechero tropical cows

Se sincronizó el estro en 36 vacas Criollo Lechero Tropical (CLT) cíclicas y lactantes utilizando PGF2α y se determinó el momento de inicio y final del estro, y el tiempo (TO) y tasa de ovulación (TAO). Posteriormente, durante el ciclo estrual natural siguiente al sincronizado se determinó la dinámica folicular (DF) y la duración del ciclo (DC). El TO después del final del estro sincronizado fue 16,5±3,6 h y la TAO 100%. En el ciclo estrual natural, 93% de vacas presentó tres ondas foliculares y 7% dos ondas, y la DC fue 22 y 19 días, respectivamente. Las vacas CLT mostraron buena respuesta a la sincronización con PGF2α, y la DF y DC fueron similares a otras razas Bos taurus productoras de carne y lecheras.

Estrus was synchronized in 36 cyclic and lactating Criollo Lechero Tropical (CLT) cows using PGF2α, and the time of start and end of estrus, time of ovulation (TO) and ovulation rate (TAO) were recorded. Also, the follicular dynamics (DF) and the duration of estrus (DC) were determined during the natural estrous cycle that followed the synchronized one. The TO following the end of the synchronized estrus was 16.5±3.6 h and TAO was 100%. In the natural estrous cycle, 93% of the cows showed three follicular waves and 7% showed two waves, and DC was 22 and 19 days, respectively. The CLT cows showed good response to synchronization with PGF2α, and the DF and DC were similar to other dairy and beef Bos taurus breeds.

Effect of alimentary regimes on body weight and reproductive parameters of native goats

Objetivou-se com esse trabalho avaliar o efeito de diferentes regimes alimentares sobre o consumo de matéria seca, variação do peso corporal e os parâmetros reprodutivos de cabras exploradas na região semiárida do Nordeste do Brasil. Foram utilizadas 56 cabras distribuídas homogeneamente em quatro tratamentos: dieta 1) caatinga e palma forrageira; dieta 2) caatinga, palma forrageira e concentrado; dieta 3) capim-buffel e palma forrageira; dieta 4) capim-buffel, palma forrageira e concentrado. Foram observados maiores (p<0,05) ganhos de pesos totais e ganhos médios diários nas cabras que pastejaram capimbuffel ou caatinga recebendo suplementação com palma e concentrado. Os regimes alimentares utilizados possibilitaram ganhos de peso de até 16 g/animal/dia durante o período seco. O desempenho reprodutivo das cabras não foi influenciado (p>0,05) pelos regimes alimentares. Conclui-se que a suplementação com palma e concentrado melhorou o ganho de peso das cabras, no entanto, não influenciou na atividade estral, taxa de parição ou prolificidade dessas fêmeas.

This work aimed to evaluate the effect of different alimentary regimes on the dry matter intake, corporal weight variation and reproductive parameters of goats raised in the semi-arid region of Northeastern Brazil. Fifty-six goats were distributed into four treatments: diet 1) caatinga and palm forage; diet 2) caatinga, palm forage and concentrate; diet 3) buffel grass and palm forage; diet 4) buffel grass, palm forage and concentrate. It was observed greater (p<0.05) total weight gain and daily weight gain in the goats which were under buffel grass pasture or caatinga receiving supplementation with palm forage and concentrate. The alimentary regimes promoted the weight gain up to 16 g/animal/day during the dry season. The reproductive performance was not influenced (p>0.05) by the alimentary regimes. In conclusion, diets receiving supplementation with palm forage and concentrate increased the goat's weight gain; however, it did not affect the estrus behavior, parturition rate or prolificity of these females.

**Allele and genotype frequency of DGAT1 gene in a cattle population**

O gene DGAT1 é um gene candidato envolvido com o conteúdo de gordura no leite. Neste estudo foram analisadas amostras de DNA de 72 bovinos leiteiros de uma população parcialmente fechada através amostras de sangue. O DNA foi extraído utilizando CTAB e proteinase K. A região alvo do gene foi amplificada por PCR e os resultados foram visualizados com a utilização de gel de poliacrilamida. Na população em estudo foi verificada a presença de quatro alelos, cujas frequências foram: A= 4,0%, B= 50%, C= 40%, e D= 6,0%. Foi verificado o equilíbrio de Hardy-Weinberg através do teste de χ², concluindo-se que a população não se encontrava em equilíbrio para o locos avaliado.

DGAT1 gene is a candidate gene involved in fat content in milk and. This study analyzed DNA samples from 72 dairy cattle using blood samples. DNA was extracted use CTAB and proteinase K. The target region of the gene was amplified by PCR and the results were visualized with the use of polyacrylamide gel. The level of significance adopted was 5% for all analysis. Four alleles were checked their frequencies were: A= 4.0%, B= 50%, C= 40%, and D= 6.0%. It was verified the Hardy-Weinberg using the Chi square test concluding that the population was not in balance.

Reproductive performance of beef heifers exposed to different bioestimulation treatments

O objetivo deste estudo foi avaliar o desempenho reprodutivo de novilhas de corte submetidas a diferentes métodos de bioestimulação. Foram utilizadas 220 novilhas Aberdeen Angus de dois anos de idade. Setenta e três novilhas foram mantidas com machos caudectomizados, 73 com vacas androgenizadas e 74 não receberam tratamento bioestimulatório. Os tratamentos tiveram duração de 60 dias préacasalamento. Os fatores fixos analisados foram os três tratamentos. As variáveis resposta foram os pesos ao início e fim dos tratamentos, ganho médio diário (GMD), o índice de prenhez e dias para a concepção (medido através da data de parto ajustada a data de inseminação). Não houve diferença (p>0,05) nos índices de prenhez obtidos entre os tratamentos. A concepção foi antecipada (p<0,01) no grupo bioestimulado por vacas androgenizadas, quando comparada ao grupo exposto a machos caudectomizados. A bioestimulação não é capaz de alterar os índices de prenhez em novilhas de corte. A utilização da bioestimulação com vacas androgenizadas antecipa a concepção em novilhas de corte de dois anos de idade.

The objective of this study was to evaluate the reproductive performance of beef heifers exposed or not to different sexual biostimulation treatments. Two hundred and twenty Aberdeen Angus heifers, 24 months old were used. Heifers were divided into three groups: group one, using teaser bull consisted of 73 heifers exposed, for 60 days previous to AI, to vasectomized males. The second group consisted of 73 heifers exposed during the same period to androgenized cows. The third group consisting of 74 heifers was the control group. After the treatments (60 days) started the breeding season. Variables analyzed were the weight at the beginning and the end of treatment, ADG, the pregnancy rate, and the interval between the start of breeding season and conception. Fixed factors considered were the three treatments. Heifers biostimulatated with androgenized cows had a earlier conception, (p<0.01) than thosed bioestimulated with teaser bull. Biostimulation can not change rates of pregnancy in beef heifers. The use of biostimulation with cows androgenized anticipates the conception in beef heifers of two years old.

Productive characterisation of a goat breed: **study of growth and CSN1S1 gene polymorphism**

The results of the productive characterisation of the Blanca de Rasquera goat meat breed are presented within the framework of a Conservation Programme. The 125 animals included in the study were randomly chosen from among six farms under an extensive production system and natural lactation. The growth of kids was characterised by quantifying body weight from birth to slaughter. The influence of sex and type of birth on growth was evaluated. Kids showed a good growth rate (123 g/day on average for the period 0-45 days), comparable to, or slightly lower than, other Spanish autochthonous meat breeds. As expected, the type of birth and sex significantly influenced weight and the growth of kids. A random sample of 36 individuals was analysed in relation to the αS1-casein gene (CSN1S1). A greater frequency (62.5%) was found for alleles associated with high αS1-casein quantity in milk, indicating its good potential and technological quality for cheese production.

En el marco de un Programa de Conservación, se presentan los resultados de la caracterización productiva de la raza caprina Blanca de Rasquera, de aptitud cárnica. Se estudiaron un total de 125 animales escogidos de forma aleatoria y distribuidos en 6 explotaciones de régimen extensivo y lactancia natural. Se caracterizó el crecimiento de los cabritos mediante la cuantificación de los pesos desde el nacimiento hasta el sacrificio. Se evaluó la influencia del sexo y tipo de parto sobre el crecimiento. Los cabritos presentaron una buena tasa de crecimiento (123 g/día como promedio, para el período 0-45 días de edad), comparable, o ligeramente inferior, a otras razas cárnicas autóctonas españolas. Como era esperable, el tipo de nacimiento y el sexo influyeron de forma significativa en el peso y el crecimiento de los cabritos. Se analizó una muestra aleatoria de 36 individuos, en relación al gen de la αS1-caseína (CSN1S1). Las mayores frecuencias alélicas (62,5%) se encontraron para los alelos asociados con una elevada cantidad de αS1-caseína en la leche, indicando dichos resultados las buenas aptitudes y cualidades tecnológicas de su leche para la producción de quesos.