Methionine supplements in chicken diets. IV. The effect of DL-Methionine supplementation over full and part of growing period on growth and efficiency of cockerels from the reciprocal crosses of White Leghorns and Australorps

Abstract

The commercial value of DL-methionine supplementation of diets based on wheat products and meatmeal has been investigated. The effects of 0.025, 0.05, and 0.20 per cent. methionine on growth and feed efficiency were studied on White Leghorn chickens up to 6 weeks of age. It was concluded that maximum dose response occurred between 0.05 and 0.20 per cent. supplement. Under simulated commercial conditions, comparisons were made between WL x AO and AO x WL cockerels fed high and low energy diets unsupplemented or supplemented with 0.1 per cent. methionine to 8 weeks of age, or 0.1 per cent. methionine to 12 weeks of age. Neither methionine supplement produced a significant improvement in body weight when the low energy diet was fed. Both methionine supplements produced significant improvements in weight when the high energy diet was fed. In both diets methionine continuously produced highly significant improvements in feed efficiency, while methionine only to 8 weeks produced a significant improvement in efficiency only in the high energy diet. There was no difference between reciprocal crosses in weight or feed efficiency.