Response to dietary protein during lactation of Meishan synthetic and European White sows fed to attain two levels of backfat at farrowing

Abstract

Meishan synthetic (M) sows and gilts produce greater weight of weaned piglets and lose more backfat and body weight during lactation than White (W) breed types (Sinclair et al., 1996a). The increased litter weight and increased fat loss of M could be due to (1) M having more fat reserves than W at the start of lactation to support a higher level of milk production, (2) M being inherently more adapted than W to partition body reserves to milk production. Commercial objectives of the M breeding programmes include a reduction of backfat, so it is necessary to establish the importance of fat reserves in the maternal performance of the breeds. The objective of this experiment was to measure the consequences of manipulating body fat reserves at farrowing by nutritional means in the two breed types.