Effect of supplementary DL-methionine in pig diets with cassava leaves as a major protein source.

A feeding trial was conducted to evaluate the effect of different levels of DLmethionine supplementation on growth performance of pigs given diets with cassava leaves and cassava root products providing 20 and 30% of the diet dry matter (DM), respectively. Twenty eight crossbred (Large White x Mong Cai) pigs with an average initial weight of 27.2 ± 1.7 kg were housed in individual pens and allocated to 7 treatments in a completely randomized design. Six treatments were arranged as a 2*3 factorial design; the factors being fresh (FCL) or ensiled (RCL) cassava leaves and 0, 0.1 or 0.2% supplementary DL-methionine. The seventh treatment was the basal (control) diet which contained (% in DM) rice bran 29, maize 23, ensiled cassava root 20, cassava root meal 10 and fish meal 15. The 6 diets in the factorial arrangement were prepared by replacing 6 percentage units of fish meal and 14 percentage units of rice bran with either fresh or ensiled cassava leaves (20% in the diet DM), plus the indicated levels of DL-methionine. The experiment lasted 80 days. Growth rates were higher, and DM and crude protein conversion rates tended to be better, for fresh compared with ensiled cassava leaves. Intakes of DM and crude protein were not affected by processing of the cassava leaves, nor by level