The Effects of Compensatory Growth and Form of Amino Acid Supply on Plasma Urea Concentration, Organ Weights and Carcass Characteristics in Gilts

2000 University of Nebraska-Lincoln Extension Swine Report. An experiment was conducted to examine the effects of compensatory growth and amino acid supply on plasma urea concentration, organ weights and carcass characteristics. Gilts were fed either a corn-soybean meal diet or a corn-soybean meal diet supplemented with crystalline lysine. Pigs were randomly allotted to either a 21-day ad libitum eating period or a 42-day restricted-realimentated feeding period. The restricted-realimentated feeding period consisted of a 21-day restriction period and a 21-day ad libitum eating period (realimentation). During the restriction period, pigs were fed to maintain body weight. During week one of the ad libitum period, gilts in the restrictedrealimentated (RR) group gained weight 41% faster (P < .01), consumed 9% less feed (P < .01), and were 58% more efficient (P < .01) compared to gilts in the ad libitum (AL) group. Ultrasound scanning measurements showed that during the restriction period, gilts had a numerical decrease in backfat and a numerical increase in longissimus muscle area. Results show that the gilts in the RR group exhibited compensatory growth during the first two weeks of the ad libitum eating period. These results also suggest that during a restriction period growing pigs are able to utilize fat stores and repartition body protein to maintain lean muscle deposition.