Efeito do ambiente e da dieta sobre o comportamento fisiológico e o desempenho de cordeiros em pastejo no Semiárido Paraibano.

Abstract

The objective of this work was to evaluate the shadow and food supplementation effect on the physiologic behavior and performance of Santa Inês lambs under rangeland conditions in the semi-arid region of Paraíba. Twenty-seven male lambs were used, with an average body weight of 21.5 kg and 120 days of age. They were randomly distributed in three environments [without shade (SS), natural shade (SN) and artificial shade (SA)] and fed growing three levels of concentrate supplement (0, 1.0 and 1.5 % of live body weight). The analysis of variance revealed significant morning x afternoon effect on rectal temperature. However, no significant effect was verified for the environment and diet factors. Breathing frequency was higher in the afternoon than in the morning in the SS (35.28 and 61.64 mov/minute) and SA (30.28 and 51.76 mov/minute) environments. The diet influenced DM ingestion in SS environment. Skin temperature was higher in afternoon than in the morning, independent of the studied factors. The animals supplemented with concentrate performed better than the control ones. It was concluded tha shading improved the indexes of thermal comfort and animal physiology and production parameters. Santa Inês showed high adaptability to the adverse conditions of the semi arid region of Paraíba. The performance of Santa Inês lambs under a buffel enriched native rangeland can be improved by supplementation with concentrate.