A genealogical and a viability analysis was carried out on the 1559 available registers for the Conservation Nucleus of Brazilian Bergamasca sheep of the University of Brasilia farm in Brazil using the ENDOG and the Vortex programs. To run the ENDOG it was used the registered data and for the Vortex it was used information obtained by a questionnaire answered by the curators of the herds. Of the animals registered, 767 had known parents, with significantly more dams known at each generation. The number of pedigrees known has increased over the generations, with higher registration of parents of sires than dams. The Computed Mean Inbreeding calculated by ENDOG was 0.29 percent and mean average relatedness was 1.52 percent. Mean Generation interval was 3.71 years with this values being lower for sires than dams. The population probability of extinction, calculated by Vortex was 17 percent and the average time to extinction was 59 years. Forty-two additional scenarios were created to determine which factors most threaten these populations which were frequency of catastrophes, lack of animal entrance and adult and lamb mortalities, especially adult female mortality. These results indicate that future breeding plans should include exchange of sires between farms to maintain low inbreeding levels and increase genetic variability and upgrade the management to control the mortality rates of animals.

A genealogical analysis of Crioula horses registered by the Brazilian Association of Crioula Horse Breeders was performed. The state of Rio Grande do Sul is the largest producer of animals with 89.85 percent of registered animals, of which 45.29 percent were males and 54.71 percent females. The inbreeding coefficient was calculated at 0.88 percent and the average relatedness was 0.65 percent in the total population (animals born in Brazil and imported). Inbreeding increased over the generations. An increase was seen in the average genetic conservation index in animals born after the year 1927 (0) until 2010 (8.67 percent). The average generation interval was 10.3 years and the average age of parents when offspring born were 10.5 years, falling in recent years. The effective population size of founders was 95.19 animals, the number of ancestors contributing to this population was 5086 where 56 ancestors explained 50 percent of the genetic diversity of the breed. Inbreeding is under control in the Crioula horse. The increase in registrations reflects the increased interest from farmers in this breed.