Effect of maternal experience and body condition on patterns of ewe-lamb bonding behaviors and pre-weaning growth performance of lambs

Abstract

Many factors, involving parity and body condition can have a profound effect on physiological and sensory determinants of maternal behavior and, consequently, the establishment of the ewe-lamb bond. Thus, exploring the factors and their interactions that influence maternal behavior is critical to improve the overall lamb survival and welfare. The aim of this study was to determine the effects of parity and body condition score (BCS) on early ewe–lamb bonding behaviors and pre-weaning growth performance in lambs. The study was carried out with 12 first-parity (primiparous; PP), 12 second-parity (biparous: BP), and 14 third or more parity (multiparous: MP) Norduz ewes and 38 singleton lambs. In the study, ewe–lamb bonding behaviors were analyzed based on parity (PP, BP, and MP) and body condition score groups (BCS ≤ 3 and BCS > 3). Behaviors of ewes and lambs from each group were monitored for a period of 3 hours after parturition, and the ewe–lamb separation test was performed within the first 24 hours after parturition. Maternal behaviors such as latency to grooming, the number of low and high pitch bleats, and preventing sucking and neonatal behaviors such as latency to successful suck, the number of bleats and the total sucking duration were determined. The live weights of the lambs were recorded every 2 weeks until the 90th day. Ewes were grazed entirely on pasture without extra feed supplementation during the pasture season. Ewes were fed with alfalfa hay and gradually supplemented with barley and concentrate throughout the winter. While the grooming duration was not affected by parity, BCS > 3 ewes had longer grooming duration than BCS ≤ 3 ewes (P < 0.05). More prevention of sucking, butting, and low and high pitch bleating were counted for PP ewes than BP and MP ewes (P < 0.05). Parallel to these results, PP lambs had the longest latency to successful suck (P = 0.046) and the highest number of sucking attempts (P = 0.033). The mean sucking duration of MP lambs was significantly longer than PP lambs (P < 0.038). Birth weight of PP lambs was lower than MP lambs, but neither parity nor BCS had a significant effect on growth performance of lambs. In conclusion, the findings of the study showed that lack of maternal experience caused a negative effect on co-operation with lamb sucking attempts, but did not significantly affect growth performance. It can be suggested that BCS had little effect on maternal behavior and growth performance of lambs for ewes with a body condition score of 2.85-3.33 during the mating period.