Avaliação de biotecnologias reprodutivas em programas de melhoramento utilizando simulação de dados

• Ano de defesa: 2008
• Autor(a) principal: Souza, Gustavo Henrique de
• Orientador(a): Torres, Robledo de Almeida
• Banca de defesa: Freitas, Marcelo Silva de , Bueno, Rachel Santos , Carneiro, Antônio Policarpo Souza
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Genética e Melhoramento
• Departamento: Genética animal; Genética molecular e de microrganismos; Genética quantitativa; Genética vegetal; Me
• País: BR
• Palavras-chave em Português: Genética; Métodos estatísticos; Mapeamento genético; Marcadores moleculares; Simulação por computador
• Palavras-chave em Inglês: Genetics; Statistical methods; Genetic mapping; Molecular markers; Computer simulation
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::GENETICA E MELHORAMENTO DOS ANIMAIS DOMESTICOS
• Link de acesso: http://locus.ufv.br/handle/123456789/1278

The aim in this study was to test the superiority of the application of multiple ovulation and embryo transfer biotechnologies on bovines breeding, in a defined time interval, as well as testing the advantage of increasing the number of descendents by mating followed by increasing the selection intensity of sires. For the simulations the software GENESYS, was used in this study. Two situations were considered to compare the efficiency on formation of breeding population. On the classic or traditional situation, a cow is mated with one sire generating one descendent by year, being necessary a seven year interval to the birth of five offsprings (first calving at three years old and calving interval of 12 months). Another situation would be the use of multiple ovulation and embryo transfer (MOET) techniques where the interval for the cow to calve at least five descendents would be only three years. Therefore, after 42 years the number of mating generations and selection would be 6 and 14 considering classical and MOET situations, respectively. The possibility of increasing the number of descendents by mating of sires using MOET (N1, N2, N3, N4 to 5, 10, 15 and 25 descendents respectively), and as a result, the decreasing of the number of selected cows were also evaluated. The efficiency of the application of the reproduction biotechnology multiple ovulation and embryo transfer (MOET) application compared to the traditional method considering the same number of descendents in the end of 42 years showed that the application of the reproduction biotechnology resulted in an average phenotypic value 27.05% higher than the traditional method (305.47±5.84 x 240.43±4.67) with an annual genetic gain rate 90.63% higher (3.26±0.14 x 1.71±0.11) than to the traditional method. Average phenotypic values were 305.47±5.84, 313.22±4.62, 316.14±4.03 and 313.44±2.80 to N1, N2, N3 and N4, respectively. By increasing the number of descendents by couple (N1 to N4) it was observed an increase on average phenotypic value on 42 years until populations N3. From N3 the average phenotypic value has decreased. The average inbreeding considering the traditional method was 0.06±0.03 while MOET value was 0.18±0.08. Thus, the application of the reproduction biotechnology was responsible for 200.79% of the inbreeding increase along 42 years. This resulted in an average additive genetic variance 59.63% lower than the traditional method (51.23±12.39 x 126.91±12.60) with a reduction rate of the annual average additive genetic variance 108.21% higher (3.47±0.36 x 1.66±0.30) than to the traditional method. MOET application increased the phenotypic value and inbreeding, with reduction on additive genetic variance. MOET could use 5 to 10 descendents by couple depending on population size.