GENETIC-STUDY OF ANDALUSIAS OVINE AND CAPRINE BREEDS

Two different breeds of Andalusian sheep, 'Grazalema Merino' and 'Lebr ijan Churro', and two different breeds oi Andalusian goats,'Andalusian White' and 'Andalusian Black', chosen by previous studies (RODERO et al. 1992a) as priority breeds for conservation, were studied. The syst ems used corresponded ro ethnozootechnic characteristics, as well as t he different biochemical-polymorphism variables. Farms were differenti ated within breeds, or between themselves, and different tests were us ed of generic and genotypic frequencies: Wright's indices, medium hete rozygosities, Whalund's variances, G test of probability of reason, et c. Also Cavalli-Sforza's genetic distance was obtained. In the Andalus ian Black and Grazalema Merino breeds, the Whalund's variances obtaine d were a result of selection, that has divided the breeds into distinc t populations differentiated spatially. Medium heterozygosities of eac h breed do nor differ much within themselves, but when each system is considered alone, discrepancies between ethnic groups are relevant. Wr ight's F indices demonstrated in the Andalusian White and Grazalema Me rino breeds, genetic heterozygosities between populations or studied h erds can be deduced, but this is not possible in the Andalusian Black. The FIS values indicated, despite the small size of the populations, that inbreeding has been avoided, probably because of the entry of for eign sires. In none of the breeds is there a significant excess of het erozygosis. The genetic distances between flocks within breeds do not differ from those found between breeds.