Digestible lysine requirement of gilts with high genetic potential lean deposition, in carcass from 15 to 30 kg

Abstract

Fifty gilts were used, with initial weight of 15.11 + 1.34 kg, distributed in a random block experimental design, with five treatments (digestible lysine levels), five replicates and two animals per stall, which were considered one experimental unit. The criteria for the formation of the blocks were the animal initial weight. Treatments consisted in a basal diet with 19.41% of CP e 3,221 kcal of ME/kg, supplemented with L-lysine HCl, resulting on diets with 0.88, 0.98, 1.08, 1.18 and 1.28% of digestible lysine. Diets were supplemented with increasing levels of industrial aminoacids, resulting on diets with constant ratio of essential aminoacids and lysine, based on true digestible. There was no effect of levels of digestible lysine on daily feed intake and daily weight gain. A quadratic effect (P < 0.06) was observed on feed conversion that improved until an estimated level of 1.08% of digestible lysine, which corresponded to a digestible lysine intake of 11.60 g/day. The level of 1,08% of digestible lysine, which corresponded to a digestible lysine intake of 11.60 g/day, provided the best performance results for gilts and a high genetic potential for lean deposition from 15 to 30kg.