Genetic diversity in the Ramo Grande cattle breed assessed by pedigree information and microsatellite markers

Abstract Text: Demographic analyses of Ramo Grande included Herdbook information on 2020 cows, 423 bulls and their offspring, collected between 1982 and 2013. On average, 10.9 calves were registered per bull and 2.6 per cow. Mean age of parents was 4.0 for bulls and 5.49 for cows, with average generation interval of 4.71 years. The reference population (1057 calves born in 2011-2013), had mean inbreeding of 4.1%, effective population size of 28 and one sire contributed with 10% of the gene pool. Analyses with 25 microsatellite loci showed high levels of genetic diversity (expected heterozygosity of 0.71, mean number of 7.2 alleles/locus). The estimated deficit in heterozygosity was 3%. Bayesian analysis indicated admixture with the exotic Holstein-Friesian in some animals. Measures should be taken to strengthen the conservation program of the Ramo Grande breed, to maintain genetic diversity and to avoid further dilution from crossbreeding.

Keywords:

Cattle

Genetic diversity

Inbreeding