Silage Intakes in Relation to the Energy Requirements of Ewes in Late Pregnancy

The extent to which the intakes of silages, of varying chemical composition and digestibilities, meet the estimated energy requirements of the ewe in late pregnancy was examined. Sixty-eight individually penned ewes were used and four silages were evaluated. The results show: i) that silage as a sole feed in late pregnancy does not meet the estimated energy requirements of ewes carrying twin lambs; ii) that silage intakes of twin-bearing ewes tend to decline in late pregnancy and thus a computed mean intake over the final 6 to 8 weeks of pregnancy can be quite misleading; iii) no clear-cut effect of the number of foetuses carried on voluntary dry matter intakes; and iv) that ewe net bodyweight losses were higher and birthweight of twin lambs lower than those normally obtained when the energy requirements were adequately met in late pregnancy.