Gross response and meat yield of broiler chickens fed different levels of digestible methionine

The current focus of genetic selection of broiler lines is on cut part yield. There is therefore a need to ascertain the methionine requirements to increase such yield. Three hundred and twenty male broiler chicks were randomly assigned to four dietary groups (digestible methionine levels) - 4.0, 5.8, 6.7 and 7.6 g/kg; 3.5, 5.1, 6.0 and 6.8g/kg , and 3.2, 4.6, 5.4 and 6.1 g/kg in the starter, grower and finisher diets, respectively. There was no significant effect of digestible methionine levels on growth response. However, breast meat yield was improved (P < 0.014) by increasing digestible methionine levels up to 6.7, 6.0 and 5.4 g/kg in the starter, grower and finisher stages. There were also improvements in weight of thighs (P < 0.012), drumsticks (P < 0.001) and wings (P < 0.013) with increased levels of digestible methionine. The results suggest that increasing digestible methionine levels could improve meat yield without altering the growth response of broiler chickens.