Impacto da utilização do xenotransplante de tecido ovariano fetal associado a produção in vitro de embriões nas estimativas de ganho genético para características reprodutivas

• Autor(a) principal: Reis, Camila Oliveira
• Data de Publicação: 2019
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFU
• Texto Completo: https://repositorio.ufu.br/handle/123456789/26051
• topic: Brahman; Ganho genético; Idade ao primeiro parto; Perímetro escrotal; CNPQ::CIENCIAS AGRARIAS

The genetic improvement of beef cattle allows greater productivity, aiming to increase the genetic gain of characteristics of economic impact. Among these traits, scrotal circumference and age at first calving are extremely important, due to the favorable correlation with reproductive precocity. The objective of this study was to analyze the impact of the use of fetal ovarian xenotransplantation on the reduction of the generation interval and, consequently, to increase the genetic gain estimate for the scrotal circumference at 450 days of age and for the first calving age in one herd of the Brahman breed. Data were analyzed from 258 males with scrotal perimeter measurement at 450 days (PE450) and 296 females with characteristic age at first delivery (IPP) were used. The analysis of database consistency and grouping of animals into groups of contemporaries were performed in SAS 9.0 software. The genetic parameters were obtained through the animal model, via Bayesian inference. The genetic gain formula (ΔG) will depend on the selection intensity (i), the heritability (h^2) and the phenotypic standard deviation of the characteristic (σ_p), being inversely proportional to the generation interval (L) ( LIRA et al., 2013). The generation intervals used were: 0.66; 3.75; 5.75; 7.75 and 10.75 years. The values of PE450 and IPP were 22.61 cm and 1167 days, respectively. The PE450 and IPP characteristics presented high and medium heritability, respectively. The characteristics of PE450 and IPP obtained greater estimates of genetic gain, with the shortest generation intervals, obtained through the fetal ovarian tissue xenotransplantation model. It was concluded that the use of the generation interval based on fetal ovarian tissue xenotransplantation, in the equational model, impacted the highest annual genetic gain estimate for the characteristics PE450 and IPP.