Effect of unwilted and wilted grass silage on the intake and performance of pregnant ewes at varying levels of concentrate feeding

Abstract

ABSTRACTIn three separate experiments a total of 144 Greyface ewes was offered direct-cut or wilted silage from week 4 to 5 of pregnancy until lambing with varying levels of concentrate during the last 6 weeks of pregnancy. Wilting resulted in a proportional increase in the intake of silage dry matter of 0·08 on average but, because digestibility of the wilted silages was lower, digestible energy intake of both silages was similar. Average change in ewe live weight from housing until after lambing was not affected by silage type and there was a small, non-significant increase in lamb birth weight on direct-cut silage. There was no evidence of any reduction in silage intake as total concentrate intake over the last 6 weeks of pregnancy increased to about 18 kg, and limited evidence of a reduction at higher levels with some indication of a greater reduction on direct-cut than on wilted silage. Compared with no-concentrate feeding the highest level increased ewe live weight by 252 g/kg concentrate and there was a non-significant effect on lamb birth weight of 13 g/kg concentrate.