Indian Journal of Poultry Science

The effectiveness of organic acids: propionic acid (PA) and butyric acid (BA) at two levels (0.2 and 0.3%) replacing antibiotic (AB-Virginiamycin 11mg/kg) from chick diets was evaluated in a feeding trial with 270 broiler chicks (Vencobb) by recording their performance, meat yield and immune response up to 42 d of age. Each diet was offered ad libitum to 9 replicates of 5 birds per replicate in battery brooders. The results indicated that organic acids, PA and BA at both levels of inclusion (0.2% and 0.3%) in diets enhanced (p< 0.01) broiler body weight by 8–10% over the AB and control diets (2154g vs 1960g) at 42d of age. Both organic acids significantly (p< 0.01) improved FCR (1.68–1.91), tibia weight (5.75–5.31g), tibia length (7.96–6.16 cm), breast muscle yield (13.68–14.77%), butreduced leg scores (1.04–1.50) and abdominal fat (7.5%) compared to AB and control diets. However, there was no statistical difference between PA and BA for all the effects recorded. Organic acids supplemented at 0.2% in diets was effective or better than 0.3% level suggesting that the former level is adequate in broiler diets. The study also suggested that organic acids, PA and BA supplemented at 0.2% was effective in replacing Virginiamycin (11mg/kg) from broiler diets without affecting performance up to 42 d of age.