Níveis de lisina em rações de suínos em terminação: um metanálise para otimizar o desempenho

Abstract

The objective of the study was to determine optimal lysine levels (Lys) in diets for finishing pigs, suitable for optimize performance and reduce feed costs, using the meta-analysis technique. Feed conversion (FC) data from 16 dose-response experiments realized in Brazil (from 2000 to 2011), which evaluated increasing lysine levels in diets were used. The feed conversion data from selected works were converted to a common basis and submitted to regression analyzes considering the lysine level as independent variable by the exponential, quadratic model and Linear Response Plateau (LRP). Based on exponential equation was calculated the variation of feed cost per kg of weight gain. The cost of basal diet (without L-lysine) was considered as R$0.70/kg, and assigned the value of 2.80 (g/g) for the FC desired. The optimal total lysine level appropriate to optimize performance, recommended by quadratic model was 1.036 %, while the optimum level recommen-ded to reduce feed costs and increase the margin was 0.980 %, when the cost of L-lysine HCl kg (78.5 %) was R$4.71. On the other hand, when the kg of L-lysine (78.5 %) increased to R$7.85, the recommended level was reduced to 0.880 %. To estimate the feed cost per kg of weight gain for growing/finishing pigs, an equation was proposed.