Effects of feeding system on rates of feeding and welfare behaviours by Karayaka male lambs with different birth weight

Abstract

ABSTRACT After weaning, 14 low birth weight (LBtW, 20.1 ± 0.92) and 14 high birth weight (HBtW, 21.1 ± 1.38 kg) Karayaka male lambs, 3 months of age, were used to compare feeding system with different dietary treatments throughout the day. While seven lambs in the each of these groups were fed ad-libitum with TMR, the other seven lambs were fed with free-choice feeding (FCF). The TMR was consisted of 80% of a commercial compound feed and 20% of roughage based on a dry matter basis (140 g crude protein and 2550 kcal ME/kg), whereas the FCF consisted of the same ingredients as that of TMR, but putted each ingredient into five separate troughs throughout the daily. Hence, there were four experimental treatments after weaning; namely TMR-fed LBtW, FCF-fed LBtW, TMRfed HBtW and FCF-fed HBtW. To determine the behavioural responses, such as eating, ruminating, drinking, standing, playing and resting of lambs, each lamb was monitored behaviourally twice a week for a period of 1 h at 04:00, 08:00, 12:00, 16:00, 20:00 and 00:00 h at 5 min time intervals twice in a week during experimental period 60 days. Changes in rate of feeding and welfare behaviours of lambs with low and high BtW in the studied times throughout the daily were not dependent on the feeding systems (TMR or FCF). Differences in body weight influenced feeding and welfare behaviours. Lambs in FCF showed more ruminating (P < 0.01) and resting (P < 0.05), but less drinking, standing and playing behaviours (P < 0.05). The present results indicated that there were significant differences in proportions of eating and drinking, rumination, resting and locomotion for Karayaka male lambs with different birth weight fed TMR or free-choice feeding.