Strategies of early weaning and concentrate supplementation on the daily behavior of lambs produced on Tifton-85 pasture

Abstract

The objective in this work was to evaluate the influence of early weaning and concentrate supplementation strategies on the daily behavior of grazing lambs. Both strategies of weaning and supplementation were combined in pairs, resulting in four production systems on Tifton-85 (Cynodon spp.) pasture: suckling lambs not supplemented; suckling lambs supplemented with concentrate in creep feeders; early weaned lambs not supplemented; early weaned lambs supplemented with concentrate. The experimental design was randomized blocks in 2x2 factorial arrangement with three replications and five lambs per replication. Four observations of behavior were performed during 24 hours, evaluating the time spent by lambs on grazing, rumination, suckling, supplementation and other activities. The behavior and distribution of daily activities performed by the lambs were influenced by the both strategies evaluated. Suckling and concentrate supplementation are important modulators of grazing activity and the absence of these nutrient sources is compensated by an increase in grazing time. This reflects the decrease in nutrient intake and the lower efficiency in harvesting forage by lambs. The increase in grazing time requires greater energy expenditure, which associated with lower harvest efficiency and low utilization of forage intake has negative impact on the performance of lambs produced exclusively on pasture.