Ewe colostrum quality on commercial Welsh sheep farms

Abstract

In advance of the 2020 lambing season, 147 Welsh farmers were engaged in active colostrum management through training and discussion groups. Sixty-four of these farmers returned data on 1295 ewes, including ewe age, breed, body condition score (BCS), number of live and dead lambs born, a description of udder condition, colour of colostrum and a Brix reading. Flock numbers were available from 43 farmers and information on late pregnancy ration from 30 farms. Results were analysed using a Brix reading cut-off of 26.5% and showed that 76% of samples exceeded this level and were considered of good quality. With an average of 20 ewe colostrum samples returned per flock, the greatest variation was found to be at the flock level with ewe nutrition considered to be the greatest driver. Concentrate feed space, silage crude protein and the supplementation of concentrates to twin and triplet-bearing ewes were all factors that indicated a potential flock level role in determining the colostrum quality. Individual level ewe factors appeared to have a much smaller role in determining the quality of the colostrum, with the ease of stripping being the main significant factors. Colostrum quality was more likely to be inadequate if the ewe was reported to be hard to strip (OR 0.56). While not significant in the final regression model, other ewe factors appeared to have an impact on the colostrum quality, such as the BCS and number of lambs born; however, lack of significance in the model may mean they are not significant or that they reflect differences in management between different flocks. As UK sheep farmers prepare for lambing 2022, and continue to optimise colostrum management and reduce levels of antibiotic given to neonatal lambs, this practical study has demonstrated how sheep farmers can be actively motivated to measure colostrum quality to determine how to optimally manage colostral antibody delivery to individual lambs.