ABSTRACT The objective was to evaluate the existence of heterogeneity of variances and its impact on the genetic evaluation of ponderal performance in sires of the Nellore breed. We used records of adjusted body weights at 210 (W210), 365 (W365), and 450 (W450) days of age. Both W365 and W450 were combined by principal component analyses using the first component (PC). Average daily gain (ADG) was obtained by d...
ABSTRACT The aim of this study was to evaluate genomic information inclusion in genetic parameter estimation of standardized body weight at birth and at 240, 365, and 450 days of age, and visual scores for body structure, precocity, and body muscularity, measured as yearlings in Nelore cattle. We compared genetic parameters, (co)variance components (estimated from Bayesian inference and Gibbs sampling), breedin...
ABSTRACT The objectives of this study were to estimate genetic parameters and genetic trends and perform principal component analysis for the following traits: body weight adjusted at 210 days of age (W210), one year (W365), and yearling or 450 days of age (W450); weight gain from birth to weaning or 210 days of age (WGBW), from weaning to 365 days of age (WGW365), and from one year to yearling (WGY); and scrot...
Resumo Objetivou-se avaliar o efeito do componente genético na expressão fenotípica de características produtivas de bovinos da raça Nelore submetidos à prova de desempenho individual. Os dados utilizados foram provenientes de 51 touros jovens participantes da Prova de Desempenho Individual de Touros Nelore realizada na fazenda experimental Capim Branco da Universidade Federal de Uberlândia. As características ...
Objetivou-se estimar as herdabilidades para as características de carcaça de área de olho de lombo (AOL), espessura de gordura subcutânea (EG) e espessura de gordura subcutânea na garupa (EGP8), medidas por ultrassonografia, em bovinos da raça Nelore Mocho, criados em bioma Cerrado. As informações utilizadas foram provenientes de criatórios da raça Nelore Mocho, participantes do Programa Nelore Brasil, da Assoc...
Genetic breeding programs of beef cattle in Brazil are including new features, mainly related to reproductive efficiency.Thus, it is necessary to study the effectiveness of selection and quantify genetic gain for these traits in herds. This study estimated genetic and phenotypic parameters and genetic trends for reproductive traits used in breeding programs for Nelore beef cattle. The traits studied were the sc...
The objective of the present study was to analyze the phenotypic inter-relationships between growth, feed intake and carcass traits in polled Nellore cattle, as well as to determine which bulls produced the most efficient progeny. The experiment was conducted in the feedlot of the Guaporé Pecuária (Livestock) Company, OB Brand. The following traits were analyzed: initial live weight (ILW); final live weight (FL...
Records of birth weight (BW) and weights standardized to 210 (W210); 365 (W365) and 550 (W550) of age in the Nellore breed were used to estimate variance components of genetic effects and predict genetic values of sires. The model included the fixed effects of contemporary group and cow age at calving as co-variable, and the additive and maternal genetic, permanent maternal environmental, and temporary environm...
Objetivou-se estimar parâmetros genéticos, utilizando inferência Bayesiana, para as estimativas dos parâmetros individuais de peso à maturidade (Â) e taxa de crescimento (<img border=0 width=32 height=32 id="_x0000_i1026" src="../../../../../../img/revistas/cr/2013nahead/a11813img06.gif">), obtidos pela função de crescimento Brody. O arquivo estava constituído de 14.563 registros de pesos e idades referentes a ...
Dados de pesos à desmama ajustados para 205 dias (P205) e ao ano ajustados para 365 dias (P365), de animais da raça Nelore provenientes de 29 fazendas de diferentes estados brasileiros distribuídos entre as regiões Norte, Sudeste e Centro-Oeste, participantes do Programa de melhoramento genético da raça Nelore (Nelore Brasil), foram utilizados para avaliar a presença da interação genótipo-ambiente (IGA), bem co...