<b>Effect of concentrate supplementation and time scales of evaluation on behavioral and physiological responses of pregnant ewes on grazing system

Abstract

This study was realized to evaluate the effect of concentrate supplementation and time scales of evaluation on behavioral and physiological responses of pregnant ewes on grazing system. The experimental design was a randomized 2 x 2 x 3 factorial arrangement (two breeds: Morada and Santa Inês; two concentrate supplementation levels: 0.5 and 1.5% of body weight; and three time scales of evaluation: 10, 20 and 30 minutes) with six replicates per treatment. The physiological parameters were influenced by period of the day and breeds, with higher values in the afternoon to Santa Inês ewes. Also, influence of concentrate supplementation was found between the breeds with greater values in Santa Inês ewes. But, it did not alter the physiological parameters among animals of the same genetic group. The grazing activity was influenced (p < 0.05) by the scales of observation intervals. Interval of 10 minutes was the most effective methodology to assess accurately the behavior of these animals due to higher number of the registries, offering higher data reliability. Morada Nova breed exhibited less time grazing (p < 0.05) on the 10-minute scale compared to 20 and 30 minutes, which were similar (p > 0.05) for such a feature. Thus, the pregnant ewes exhibited high adaptive capability with observations of 10 minutes for better description of grazing activity in Morada Nova.