Reproduction in Indonesian sheep and goats at two levels of nutrition

Abstract

Oestrus and ovulation were recorded for eight oestrous cycles after sheep and goats were put onto maintenance or supramaintenance levels of nutrition. Oestrous cycles were longer and more variable in goats than in sheep (20.3 ± 0.3 and 17.4 ± 0.2 days respectively), but in neither species was the incidence of oestrus affected by level of nutrition. There were no significant differences between sheep and goats in average body weight or mean ovulation rate. Animals fed at a maintenance level showed no significant changes in average body weight (19.0 ± 0.3 kg) or mean ovulation rate (1.69 ± 0.01). At the supramaintenance level, on the other hand, mean body weight increased progressively to a maximum of 24.8 ± 0.5 kg, and mean ovulation rate increased to a maximum of 2.65 at the sixth oestrus after the beginning of supramaintenance feeding. The effect of supramaintenance feeding on ovulation rate was reflected in subsequent lamb and kid production.