Effect of light restriction on the performance of broilers fed conventional and non-conventional growth promoters

This study was performed to investigate the effect of light restriction (RL) on performance of broilers fed conventional and non conventional growth promoters. One hundred and eighty day-old broiler chicks were randomly distributed into four groups (A, B, C and D), each having five replicates. The experimental period was 42 days and all the birds were reared in an open house. Groups A and B were reared under continuous light and given diet containing conventional (Zinc bacitracin: 0.5 gms/kg of feed) and non conventional growth promoters (Botanical growth promoter 1 (B.G.P 1):1 gms/kg of feed), respectively. Group C and D received regular light (RL: 20 hrs light and 4 hrs dark) and were fed same conventional and non conventional growth promoter, respectively. Weight gain, feed intake and FCR were not affected by either LR or feeding conventional and non-conventional growth promoters. However, microbial count was higher in groups fed diets containing conventional growth promoters as compared to those given non conventional growth promoters. Significantly higher (P<0.05) mortality was found in group A (8.8%) compared to C (6.6%), B (4.4%) and D (0%). Light restriction didn’t affect growth performance of the broilers, yet overall economic performance was improved due to reduced mortality and cost of electricity.