Performance of broilers fed with different levels of methionine hydroxy analogue and DL-methionine

One-day-old male Ross chicks were used in an experiment designed to compare two methionine sources, DL-methionine and methionine hydroxy analogue free acid (MHA-FA), and four different levels: 0.41; 0.47; 0.53; 0.59% (starter diet); 0.35; 0.41; 0.47; 0.53% (grower diet); and 0.30; 0.36; 0.42; 0.48% (finisher diet). One thousand two hundred and eighty chicks were housed in 32 experimental floor-pens (40 birds each) and fed 8 experimental diets based on corn and soybean meal for 47 days. The effects of methionine sources and levels were evaluated by performance data, carcass and cut yields, feather yield and abdominal fat content. Data were analyzed as a completely randomized design in a 2x4 factorial arrangement (2 sources and 4 levels), with 8 treatments and 4 repetitions. Analysis of variance was performed using PROC GLM of SAS©. Data indicated DL-methionine to be more effective in promoting growth than MHA-FA, and weight gain increased numerically in response to increasing levels of methionine in all phases