NM 03. Biological and economic L-lysine levels on starter broiler diets (1-21 days)

Abstract

An experiment was carried out in order to estimate the optimal biological (NOB) and economic (NOE) level of L-lysine on starter broiler diets to be fed from 0 to 21 days. It was evaluated the effect of seven dietary levels of L-lysine (.8, .9, 1.0, 1.1, 1.2, 1.3 and 1.4 %) on feed intake and weight gain. Significative effects (P<.05) were detected on feed intake and gain. The regression parameter estimates of ten models were calculated in order to predict the feed intake and weight gain responses. An exponential model (Intake or Gain=a*(Lisb)*e(-c*Lis) , was chosen, among the ten models, as the best model. The model selection based on the mean square error (Intake: 1958.85; Gain: 882.78). Two econometric models were built in order to maximize gain and profits, respectively.