Some comparative aspects of the energy and nitrogen metabolism of Large White and Duroc female pigs during growth

摘要

The energy and nitrogen metabolism of Duroc and Large White female pigs offered 2 levels of feeding were compared in open-circuit calorimeters at 30 and 80 kg liveweight. Fasting heat production was measured after the final energy balances. The digestibilities of energy and nitrogen were lower for the Duroc than the Large White pigs, but only nitrogen digestibility was significantly different (PO.05). During this experiment (in which the pigs increased from 20 to 90kg liveweight) the 2 genotypes had similar growth rates and feed conversion ratios.