Changes in body composition of the sow during pregnancy

Abstract

The body composition of four sows slaughtered on the 110th day of pregnancy was compared with that of four non-pregnant sows slaughtered after 110 days on the same feeding regime and with four sows slaughtered at the beginning of the 110-day period. Mean weight gains in 110 days of the pregnant and non-pregnant sows were 35·9 and 4·3 kg. respectively; the extra gain of pregnant sows over that of the non-pregnant was located in the carcass and reproductive organs. The extra carcass gain of pregnant sows was in muscle, fat and mammary tissue. The greatest proportion of the extra fat of the pregnant sows was in the back region while the greatest proportion of extra muscle was in the belly. There was considerable variation between individuals in moisture, nitrogen and fat contents of sample muscles and treatment differences were not significant.