Estratégias de sombreamento para bovinos de corte em confinamento no semiárido mineiro

Abstract

The use of shading strategies on intake behavior, body surface temperature and performance of Nellore beef cattle in the semi-arid region of Minas Gerais was evaluated. The experiment took place in two stages. The first occurred during the rearing, between May and July 2019. The highest values of air temperature and climatic indexes were recorded in the afternoon in the three treatments. The highest frequency of animals in the trough occurred in the morning, while rumination occurred in the night and early hours. The highest values of body surface temperature were recorded in the animals in the corral with shade during the month of May, and in the afternoon in the three treatments. The animals treated with natural shading showed higher average daily gain. In the first stage, it was concluded that the highest frequency of animals in the trough was observed in animals with natural shading, better balance in body surface temperature throughout the day and periods, and better average daily gain. The second stage occurred in the termination phase, between August and October 2019 and it was observed that the relative humidity in the shaded environments had the lowest values. The animals frequented the trough in the morning and remained idle in the shade in the afternoon. The highest frequency of animals ruminating under space with and without shading occurred in the night and early morning. The afternoon was marked by an increase in body surface temperature. It is concluded that, when the BGHI values increased, the animals reduced the frequency to the trough and increased the idleness, and in the environment with natural shading, the greatest weight gain and average daily gain were registered.