Archivos de Zootecnia
versión impresa ISSN 0004-0592
GOMEZ, M.; LEON, J.M. y DELGADO, J.V.. Demographic analysis of the equine breed Spanish-Arabic. Arch. zootec. [online]. 2011, vol.60, n.231, pp.341-344. ISSN 0004-0592. http://dx.doi.org/10.4321/S0004-05922011000300006.
The breeding program of the Spanish-Arabian horse is in process of development and, for this reason, is necessary to know its population structure from the information registered in the Herd Book to design strategy for its improvement and utilization. The demographic parameters were calculated having a census of 1041 animals, taking part of the selective nucleus; the effective population size was 1036.94 (553 females and 488 males) with a sex ratio of 1.13. With a correct reproductive management we expect an increasing of the inbreeding rate by generation of 0.000482 (0.048%) and by year of 0.000055 (0.005%), something expected because the total generational interval of 8.65 years (females 8.95 and males 8.31), value too high in the equine species, but common, because of a lot of animals are employed only in sport activities. The level of replacement observed was 12.66% in females and 11.68% in males, with mean ages of 8 and 9 years in males and females respectively. The good management of the genetic progress is demonstrated, also maintaining the level of genetic variability and dynamism of the breed.
Palabras clave : Horses; Effective size; Generation interval.