Nitrogen balance studies with the milk-fed lamb

Thirty-three cross-bred lambs were given reconstituted dried whole cow's milk from 1 week of age at different levels of intake and at different frequencies of feeding. 2. Feeding frequency had no effect on live-weight gain, N retention or total body composition. 3. Lambs given two feeds daily had significantly heavier abomasums than pair-fed lambs given six feeds daily. 4. The weights of fat, protein (N x 6.25) and water in the body were closely related to empty body weight; body composition (% of empty body) was not significantly affected by the level of milk intake or by the rate of growth. 5. Live-weight gain was closely related to energy intake (r = +0.99) and to N retention (r = +0.97). A live-weight gain of 100 g was associated with an intake of 511 kcal and a N retention of 2.28 g N.