Population structure of the registered Tabapuã cattle in Brazil

Abstract

The population structure of the registered Tabapuã cattle in Brazil was described. Descriptive statistics of the distribution of the number of progeny, the generation interval, F-statistics, effective number of founders, ancestors, reminiscent genomes and effective population size were estimated using pedigree records from registered animals from 1971 to 1998. In the last period studied (1994-1998), 37,778 animals, 18,736 males and 19,042 females from 136 breeders were registered. The generations intervals calculated in each of the four periods 1979-1983, 1984-1988, 1989-1993 and 1994-1998 were, respectively, 6.26, 7.18, 7.68 and 7.56 yr for parent-progeny and 6.18, 6.43, 6.99 and 7.27 yr for parent to parent. The effective size of the population, founders, ancestors and reminiscent genomes in each of these periods were respectively: 378, 218, 213 and 181; 131, 254, 202 and 163; 73, 150, 119 and 94; 55, 112, 78 and 61.