Meat meal in the diet of the early-weaned pig IV. The supplementation of diets with tryptophane, lysine and methionine

Abstract

Two experiments were conducted with 72 pigs between 28 and 56 days of age to study the effect of tryptophane supplementation on their performance when fed on diets containing wheat and meat meal. In the first experiment, pigs were fed on a basal diet (Diet 1) or on the same diet supplemented with calcium dihydrogen phosphate (Diet 2), bone meal (Diet 3) or bone meal plus tryptophane (Diet 4), all to 3.1% calcium. The weight gains of the pigs (315 g day −1) fed on Diet 3 were significantly lower than that of the pigs fed on the other three diets (363 g day −1). The feed conversion ratios showed a similar trend. Diet 3 contained 0.16% tryptophane while the other diets contained 0.18–0.19% tryptophane. The crude protein, lysine and methionine contents of all diets were similar. In the second experiment, a basal diet containing meat meal and bone meal was supplemented with tryptophane, lysine plus methionine or all three amino acids. Feed intake was increased by all amino acid supplements. Weight gains were improved significantly (57%) by the addition of all three amino acids to the diets, but the improvements due to tryptophane alone (28%) or methionine plus lysine (35%) were not significant. Tryptophane supplementation alone or with lysine plus methionine increased the nitrogen retention of the pigs. It was concluded that the requirement for tryptophane of pigs between 28 and 56 days of age was greater than 0.16% of diets containing wheat and meat meal.