The impact of colostrum quality on lamb performance to weaning

Ty Coch farm has a sheep flock of 270, mainly Aberfield ewes which lamb in mid-February to March. Lambs are finished throughout the summer/autumn months, with the lambs sold under a supermarket contract.

The rearing percentage has dropped during the last two years whilst tackling an outbreak of Maedi Visna and the after effects of the dry summer of 2022. The majority of these losses occurred in the few weeks following lambing. A study also concluded that most pre-weaning lamb deaths on Welsh farms occur within the first week of life (Hybu Cig Cymru Lamb Losses Project). 

Colostrum quality and quantity of intake plays a significant role in avoiding pre weaning lamb mortality. Measurement of colostrum quality using a Brix refractometer is a common practice on dairy farms, however it has not been common practice on sheep farms. Variation in colostrum quality has been reported in studies between ewes, with factors such as the ewe’s age, litter size, udder health, time of year, breed, genetics and late gestation nutrition having varying levels of significance. 

The project’s aim is to monitor the colostrum quality at lambing, identifying what ewe related factors have the greatest impact on the quality of the colostrum. The data collected will give us an indication of areas that need improving and also the longer-term impact colostrum quality has on lamb performance to weaning. Increasing the rearing percentage by 5% should increase lamb sales by £1,875 per annum, scaling up to an additional 30% in rearing percentage would equate to £11,250 per annum.

The project will also contribute to the Sustainable Land Management outcomes including:

• Contribute to high flock health and welfare

• Resource efficiency