Data from Brasileiro de Hipismo Stud Book, collected by the breed Association (ABCCH), from July 1977 to September 1998 were analyzed. Final data set included 19,303 animals, 11,508 Brasileiro de Hipismo (BH) and 7,795 of other foundation breeds. Data were analyzed for frequency, central tendency and range of variation according to owner, breeder, sex, type of registration, county and state of birth and foundation breeds. The frequency of crosses using foundation breeds and inbreeding coefficient according to year of birth and sex were estimated. Generation number for each animal, generation interval and effective population size (Ne) were calculated. Among the 20 breeds used in the formation of the BH horse, the most important were: Thoroughbred (15.0%), Hanoverian (8.1%), Westphalian (5.2%), Holsteiner (4.8%), Trakehner (4.1%), graded BH (22.5%) and unknown pedigree animals (21.9%). The records came from 14 states and 76% of the animals were registered in São Paulo State. The maximum number of generations was 3.12 (one animal), with 59.7% of the horses in the first generation and 24.1% in generation 1.5. Generation interval was 9.7 years, 10.4 for males and 9.3 for females. The Ne was 253 animals, and the inbreeding coefficient was close to zero.
Horse; Brasileiro de Hipismo; origin; population structure; inbreeding
