Studies on the milk yields of Scottish Blackface ewes

Abstract

1. Milk yields of thirteen Blackface ewes with single lambs were estimated over a period of 6 weeks at the hill farm of Glensaugh (Kincardineshire) and a further twenty-nine at Stanhope (Peeblesshire).2. The estimated average total milk yield over 6 weeks was 159 lb. at Glensaugh and 96 lb. at Stanhope. Recorded yields ranged from 86 to 220 lb. at Glensaugh and from 65 to 131 lb. at Stanhope.3. The average daily live-weight increase of lambs was 0·72 lb. at Glensaugh and 0·43 lb. at Stanhope. Daily live-weight increases ranged from 0·23 to 0·91 lb.4. At Glensaugh the average lactation curve reached a maximum 24 days after lambing. At Stanhope, the average lactation curve showed a peak 10 days after lambing and another peak 32 days after lambing. The lack of uniformity in this curve was attributed to changing conditions of nutrition.5. Linear regression was found between ewe milk yield and daily live-weight increase in lambs, and the correlation between ewe milk yield and ewe live weight was highly significant, though the regression coefficient is fairly small.6. Four samples of ewe's milk were analysed.7. The correlation between ewe milk yield and daily live weight increase in lambs persisted when figures representing other breeds of ewes (with single lambs) were included in the calculations.