The intake and performance of ewes offered concentrates and grass silage in late pregnancy

Abstract

ABSTRACTMasham ewes carrying single, twin or triplet foetuses were offered a ration of concentrates which increased from 200 to 650 g per ewe per day over the last 7 weeks of pregnancy in 2 years. Silage was offered ad libitum and the voluntary intake of each ewe was measured. In the first year, 30 ewes were offered a poorly-preserved, wet silage (A) which had a low digestibility, followed by a better-preserved silage (B) which had a higher digestibility and dry-matter concentration. There was an increase in silage intake when the change was made from A to B. In the following year, 32 ewes were offered silage (C) which was well preserved, similar in digestibility to B but with a lower dry-matter concentration. The ewes ate more silage organic matter (g/kg live weight) with C than A (12·77 v. 9·34) in weeks 15 to 17 of pregnancy but more of B than C (13·76 v. 10·38) in weeks 19 to 20. Ewes carrying single lambs ate more silage and had a slower rate of decrease in silage intake when the concentrate ration was increased as pregnancy progressed. As litter size increased there-was either greater loss or smaller gain in body condition score.