Sows were weighed individually at placement (110 ±2 d of gestation) and at weaning (22 ± 2 d). Sow BW at farrowing was estimated assuming 0.7-kg daily gain from the day of placement to the day of farrowing based on a daily ME intake of 8 Mcal (Close et al., 1984) minus litter weight at birth, which included pigs born alive,stillborn pigs, and mummified pigs, and the estimated weight of the placenta and fluid (Noblet et al., 1985). Sow growth rate was calculated as the difference between BW at weaning and estimated BW at farrowing divided by the number of days of the lactation period