Effects of maduramicin, salinomycin and dietary level of wheat on the performance of broiler chickens

In a 2 x 2 x 4 factorial experiment, the growth performance of 1440 broiler chickens was measured from 1-d to 49-d of age. The 16 treatments consisted of the factorial combinations of two sexes (male and female), two anticoccidial agents (maduramicin and salinomycin) and four dietary levels (0, 200, 400 and 600 g/kg) of wheat. In the starter phase (1 to 21 d), neither the anticoccidial agents (ACA) nor the dietary level of wheat had any significant effect on the growth performance of chickens. In the finisher phase (22 to 42 d) the growth rate of chickens given the diets with maduramicin was reduced by 2.7% and the difference in bodyweights between the groups of chickens given the diets containing either maduramicin or salinomycin was reduced to 1.8% at the end of the drug withdrawal period at 49 d of age. Maduramicin reduced the food conversion efficiency of female chickens by 1.4% and increased the litter moisture content. Neither maduramicin nor salinomycin had a significant effect on dressing percentage, liver weights, or mortality. Dietary level of wheat had no significant effect on the growth of broiler chickens in the starter or finisher phases. After the withdrawal of drugs, chickens given the diet containing 600 g/kg of wheat ate more food and utilized food less efficiently than those given the other diets with lower levels of wheat. Male broiler chickens grew at a faster rate and converted food more efficiently than the females in all three phases of the experiment. The mortality rate in males due to the acute death syndrome was higher than in females. High dietary levels of wheat tended to increase the incidence of acute death syndrome. There were no significant interactions between the dietary level of wheat and the anticoccidial agents on any of the performance characteristics in broiler chickens.