Efeito de polimorfismo nos loci CSN1S1, GH, DGAT1 e POU1F1 sobre os valores genéticos de produção e composição do leite de cabra

• Autor(a) principal: Melo, Ana Lúcia Puerro de
• Data de Publicação: 2012
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1352
• topic: Fator de transcrição; Hormônio do crescimento; Polimorfismo e VNTR; Transcription factor; Polymorphism and VNTR; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::GENETICA E MELHORAMENTO DOS ANIMAIS DOMESTICOS

The aim with this work was verify if polymorphisms in the goat CSN1S1, GH, DGAT1 e POU1F1 genes are associated with milk production until 270 days of lactation, lactation length, somatic cell count, production and percentages of fat, protein, lactose and total dry extract in milk. For this purpose were considered 2173 lactations of 1064 Saanen and Alpine goats, belonging to the Goat sector of Federal University of Viçosa, used to estimate breeding values for these characteristics. The animal model used contained the random effects of animal and permanent environment, and the fixed effects of contemporary group, type of kidding, genetic grouping, and kidding order. Genotypes were obtained from 215, 184, 104 and 182 females, respectively, for CSN1S1, GH, DGAT1 and POU1F1. To check the effects of genotypes on breeding values of the characteristics, analyzes of variance, estimates of contrasts and comparisons of means by Tukey test (α=0.05) were performed. Association was observed between the different genotypes of CSN1S1 and genetic values of most traits. In addition, evidence was found of overdominance effects among alleles in the AE genotype for lactation length, production of protein, lactose and total dry extract and fat percentage in milk. No effect of GH and POU1F1 genotypes on breeding values of production and quality characteristics of goat milk was observed. The VNTR polymorphism identified in the promoter region of the DGAT1 gene had an influence on the duration of lactation, and the allele with more tandem repeats showed a positive association with this traits.