Visão multivariada do ambiente climático e desempenho de bovinos nelore confinados no semiárido

Abstract

The objective was to evaluate, through principal component analysis, the effect of different confinement structures on climatic conditions, nutrient consumption and performance of Nellore males in the finishing phase in a semi-arid region. Data from 225 Nellore bulls, noncastrated, with initial mean body weight (BW) of 294 ± 19 kg and age of 24 months were used. A completely randomized design was used, with three confinement structures (no shading, natural shading and artificial shading with shade 50% light interception), with a total of 75 repetitions (each animal was the experimental unit). The finishing time of the animals in confinement was 107 days. It was found that the first 2 components explained 99.65 (no shading), 97.32 (artificial shading) and 99.89 (natural shading) of the total variation present in the data set. The variables: Black globe temperature index (0.88); radiant heat load (0.96; 0.99; 0.76); black globe temperature (0.96) and hot carcass weight (0.64) had the greatest influence on the confinement structures. It was concluded that the climatic and consumption variables ranked with the greatest impact on the confinement structures. Artificial shading with shade 50% light interception contributed positively to the hot carcass weight of confined Nellore cattle.