Lamb and milk production from Booroola ewes supplemented in late pregnancy

Abstract

Booroola ewes in moderate body condition on pasture, were either not supplemented, or supplemented prior to parturition with lupin grain for 9 days in a preliminary experiment, or with lupin or oat grain for 17 days in the main experiment. Measurements included lamb birth weight and survival and, in the main experiment only, ewe milk production and lamb immunoglobulin concentrations. With 9 days of lupin grain supplementation, lamb survival to weaning increased by about 12% (P<0.05), size of litter weaned increased from 1.26 to 1.52 (P<0.01) and lamb birth weight increased by about 0.2 kg (P<0.01). In the main experiment, supplementation with lupins resulted in 95% survival to day 9 of twin-born lambs, compared with 68% for lambs from control and oat-fed ewes (P<0.05). Extra lamb losses, due to starvation in the unsupplemented group, were matched by losses due to dystocia in the fed groups. Lamb birth weights, and ewe milk production and composition, were similar across treatments. During the feeding treatment period, only the lupin supplemented ewes maintained their fat score while the other ewes lost 0.5 of a fat score (P<0.01). Fewer (P<0.1) multiple-born lambs from lupin supplemented ewes had low serum immunoglobulin scores, indicating that the lupin supplement may have affected production or intake of colostrum.