Effects of Water Restriction on Nitrogen Retention and Carcass Composition of Pigs

Abstract

Four experiments using weight gain, carbon-nitrogen balance and carcass analysis techniques were conducted to determine if water restriction under conditions of equalized feeding would affect digestibility, feed efficiency, protein retention and fat deposition. In all experiments the restriction of water resulted in a significant increase in the deposition of body fat. More fat was also deposited per kilogram of feed consumed in the water-restricted group. The total amount of protein synthesized showed little or no reduction as a result of water restriction but the percent of protein in the dry matter of the carcass was significantly reduced in all carcass studies. Highly significant differences in the protein and fat content of carcasses were obtained in one experiment, when water was restricted to a level of 2 kg./kg. of feed compared with controls that received water ad libitum. Severe restriction of water to a level of 1.25 kg./kg. of feed generally resulted in a reduced rate of gain, part of which could be accounted for by reduced “fill”. The digestibility of dry matter and protein was not affected at any level of water restriction.