Previous research suggests that the feeding stratagem employed during a particular stage of the reproductive cycle may evoke an immediate response and/or a more long-term response in reproductive performance. This trial was designed to investigate the effect of feed restriction during lactation on reproductive performance when lactation periods of 10 and 35 days were employed.

Eighty, second to fifth parity Large White x Landrace sows were used in the experiment. The sows were allocated on a parity and liveweight basis to one of the following four lactation treatments:-

1. 1) 35 day lactation; fed 7 kg/day of a standard proprietary diet during lactation

2. 2) 35 day lactation; fed 3 kg/day during lactation

3. 3) 10 day lactation; fed 7 kg/day during lactation

4. 4) or 10 day lactation; fed 3 kg/day during lactation.

All sows were then fed 3 kg/day during the weaning to remating interval and 2.2 kg/day throughout gestation. Creep feed was offered ad libitum to the litters of sows on treatments 1 and 2 from 10 days post partum. Liveweight and backfat (maximum shoulder, P2 and minimum loin) measurements were taken at regular intervals throughout the experimental period. Piglet weaning weights and subsequent birth weights were recorded.