The effects of quantity and distribution of milk substitute on the performance of artificially reared lambs to forty-eight days of age

Abstract

SUMMARYTwenty-seven groups of Finnish Landrace × Dorset Horn lambs, each of two males and two females, were offered daily quantities of 180, 248 or 343 g milk substitute dry matter (DM) for 21, 29 or 40 days. The environmental temperature was 18°C during the first 21 days of rearing, and concentrate pellets and clean water were always available. From 22 to 48 days of age the lambs were offered 150 g of hay per week.For lambs offered 180 g milk substitute DM, increasing the number of days before weaning increased the daily live-weight gain over the 47-day experimental period. For daily allowances of 248 and 343 g of milk substitute, greater gains were effected only by delaying weaning from 21 to 29 days.Increasing the daily allowance of milk substitute DM had little effect on the daily gain of lambs weaned after 21 days but increased gain by lambs weaned at 29 days. For lambs weaned after 40 days growth rate was increased only by the first increment of milk substitute DM. Intake of solid food began when the lambs were 3 weeks old and total intake of concentrates was inversely related to total quantity of milk substitute DM consumed and in general was less when weaning was later.The overall efficiency of conversion of total DM consumed to live weight was positively related to total milk substitute DM consumed and tended to be greatest when weaning was later. A daily allowance of 180 g milk substitute DM for 21 days gave the lowest food cost per unit of live-weight gain.The incidence of navel sucking is discussed.