To establish the effect of an Inadequate dietary energy intake during lactation on the repletion of maternal energy and protein stores post-weaning.

Forty-two crossbred, multi-parous (parity 2 to 5) sows were randomly assigned to diet on day-1 of lactation based upon ancestry and parity, Diets were (1) high-energy (66.9 MJ/day) and (2) low-energy (33 MJ/day). Lactation diets were prepared with maizestarch and soyabean meal and formulated to provide equal intake of all nutrients except energy during the 28-day lactation. Total daily nutrient intake was achieved in four proportional meals All litters were standardized to nine pigs/litter on day-1 of lactation. On day-14 of lactation, daily milk yield was estimated by the Weight-suckle-welgh method. Sows were weighed on day-1, day-21 and day-28 of 1actation. Maternal weight change was calculated using maternal weight postpartum and at weaning. On day-28 of lactation, ten sows (weight 182 to 258 kg) from each treatment were selected at random and assigned to metaboilsm crates for a 35-day post-weaning nitrogen and energy balance experiment.