Bioeficácia da lisina-sulfato para frangos de corte

Abstract

The present research had as objectives to study the bioefficacy of lysine sources using measures of performance, weight gain and feed conversion as evaluation variables. Bioefficacy measures were performed using simple linear regression (slope-ratio) analyzes and multiple linear regression for each measure of bird performance. A standard source of lysine (L-Lysine HCl), L-Lysine Sulfate and a control treatment without addition of synthetic lysine, corresponding to the lowest dietary lysine level 0.90% for the initial phase and 0.85% of lysine for the final phase, totaling 9 treatments and 8 replicates, distributed in a completely randomized experimental design. For the initial phase the digestible lysine levels of the diets were 1.00; 1.10; 1.20 and 1.30% and for the final phase, the levels of 0.95; 1.05; 1.15 and 1.25%. 2016 broilers were used for the initial phase and 1800 for the second final phase. In the initial stage besides performance, the chest yield and meat quality were also measured, and for the final stage, besides these measures, the carcass yield was also evaluated. L-Lysine Sulphate presented better bioefficacy results for feed conversion and weight gain in both methods used and in both phases studied. The results of the sulfate source bioefficacy for the initial phase using the weight gain and the feed conversion were 113.25 and 113.18%, respectively, and for the final phase the values were 111.4 and 110.0% for slope-ratio and multi-linear regression, respectively. Regarding the performance in both phases, the sources of lysine used promoted a positive effect on the growth of the broilers. When evaluating meat quality, no significant differences were observed between baking weight loss. When evaluating the objective color in both phases it was possible to observe the effect of the sources as well as the levels when being supplemented with lysine.