A meta-analysis was conducted to evaluate broiler response to partial or total substitution of corn by sorghum and millet and to determine the effect of soybean meal replacement by cottonseed meal in the broiler diet. The database included 190 treatments from 29 experiments published from 1990 to 2013. Bird responses to experimental diets were calculated relative to the corn-soybean meal control diet.
Results showed that diets containing millet led to similar performance as the corn-based ones for all parameters, whereas sorghum-based diets decreased growth performance. No effect of the level of substitution of sorghum on feed intake was found; however, growth performance decreased when the level of substitution of corn by sorghum increased. Results obtained for sorghum pointed out the necessity to find technological improvements that will increase the utilization of these feedstuffs in broiler diet.
Cottonseed meal was substituted for soybean meal up to 40% and found to increase feed intake while reducing growth performance. Young birds were not more sensitive to these ingredients than older birds since there was no negative effect of these ingredients on performance in the starter phase. The research group plans to validate these statistical results in vivo and evaluate the interactions induced with the simultaneous inclusions of sorghum, millet and cottonseed meal in broiler feeding.