Effects of feeding varying amounts of a grain/forage diet during late gestation and lactation on the performance of Matebele goats

Abstract

Individually-penned Matebele does were randomly allocated to three dietary treatments during gestation (0·66, 0·50 and 0·33 MJ ME/kg metabolic weight) and subsequently offered either 0·95 or 0·6 MJ ME/kg metabolic weight during lactation in Gwanda, south west of Zimbabwe, in 1990. The diets offered consisted of veld and lucerne hay and maize grain in proportions of 0·56, 0·24 and 0·2, respectively.

Reducing the amount of energy consumed from 0·58 to 0·26 MJ ME/kg metabolic weight in the last 7 weeks of gestation resulted in does suffering a net loss in body weight (−2 kg) and body condition score, although it had no significant effect on the birth weight of single kids.

Reducing feeding in the first 15 weeks of lactation from 0·95 to 0·59 MJ ME/kg metabolic body weight only had minor effects upon liveweight and body condition score change of the does and had no effect on the growth of kids. Amount of feed offered in lactation had a positive effect upon milk yield and there was a trend for yields to increase proportionally to pre-partum dietary intake. Diet had no effect upon milk composition. It was concluded that the benefits of supplementary feeding are small and may not justify the extra costs entailed in smallholder systems.