Effects of Extending Milk Replacer Feeding during the Fattening Period on the Behaviour and Welfare of Lambs: A Preliminary Study

SIMPLE SUMMARY: Artificial milk feeding in fattening lambs would promote the functionality of the reticular groove reflex in order to avoid the rumen fermentation of selected feed supplements included in the milk replacer. However, there is a lack of information of the behavioural and welfare effects of such practice. Therefore, we studied the effects of extending or not milk replacer feeding during fattening with a high concentrate diet on the behaviour of 16 non castrated male lambs of the Manchega breed (eight lambs were in the group that were fed daily a bottle of milk, and the other eight were in the fully weaned group) by means of a video recording system. Both groups consumed the same solid diet (concentrate plus cereal straw) and were kept under the same conditions. Weaned lambs showed longer resting episodes and a higher frequency of self-grooming, whereas unweaned lambs showed a higher frequency of interaction behaviour. From the interpretation of such behaviours in the conditions of the present study, we concluded that the welfare status was almost similar in both groups. ABSTRACT: There is a lack of information on the behavioural and welfare effects of sustaining artificial milk feeding in fattening lambs. Therefore, the present work aimed to study the effects of prolonged artificial milk feeding during fattening with a high concentrate diet on the behaviour of lambs. The behaviour of 16 non castrated male lambs of the Manchega sheep breed (eight lambs were in the group that were fed daily a bottle of milk, and the other eight were in the weaned group) was recorded with four fixed cameras just before bottle feeding (~8:30 a.m.) of the unweaned group till four hours later, every day for 7 weeks. The solid diet (pelleted concentrate plus cereal straw) and housing conditions were the same in both groups. Solid feeds were offered ad libitum. There were no differences between groups in time spent eating nor in drinking, playing, scratching and oral activity behaviours (p > 0.05), but resting episodes were longer in weaned lambs (p < 0.05). Weaned lambs presented a higher frequency of self-grooming behaviour (p < 0.05), while the unweaned group performed a higher frequency of interaction behaviour (p < 0.05). In conclusion, the behaviours of lambs that were fed daily a bottle of milk during the fattening period did not substantially differ from the weaned individuals.