<b>Tryptophan requirements in piglets (6 to 11 kg) based on ideal protein concept</b> - DOI: 10.4025/actascianimsci.v28i2.646

Abstract

This study aimed to determine the total tryptophan requirements in a total of 72 piglets weighing 5.80 to 11.40 kg, based on the ideal protein concept. The animals were alloted in a randomized block design with four treatments and six replications. The experimental diets presented different levels of total tryptophan (0.26; 0.29; 0.32 and 0.35%), and constant levels of lysine (1.60%), methionine (0.44%) and threonine (0.97%). The piglets weighing 11.40 to 19.90 kg all received the same ration. No significant differences were observed for any performance variables (daily food intake, daily weight gain, daily weight gain adjusted to same food intake and food conversion) and plasma urea level. The animals receiving 0.29% of the total tryptophan showed a 7.2% larger daily weight gain when compared with animals receiving 0.26% of tryptophan. The economical viability study indicated the level of 0.29% of total tryptophan as the most economical, suggesting a total lysine:tryptophan ratio of the 100:18.