Weaning Age of Lambs Creep-Fed While Grazing on Marandu Pasture

This study aimed to examine the weaning age (60 and 90 days) of lambs supplemented while grazing on Urochloa brizantha cv. Marandu pasture. Production performance, incidence of worm infections, intoxication, and production cost of lambs, beside that body condition and occurrence of single or twin births in the ewes were evaluated, by two consecutive years. There was no effect of year. Lambs weaned at 90 days consumed more supplement (281.0 g/day) than those weaned at 60 days (210.2 g/day) and showed a higher total weight gain (20.76 kg vs. 14.97 kg). Weaning age did not influence the occurrence of worm infections and intoxication by Urochloa spp. in the lambs, dam weight or body condition score (BCS). Ewes with single-born showed a better BCS (1.8 points) than those ewes had twin-born (1.4 points). The costs of supplementing the lambs and the effective operating cost were higher when the lambs were weaned at 90 days of age. There was no difference for intake, lamb performance between the weaning age groups. We recommend to wean lambs at 90 days in a creep feeding system.