Organic acids as a replacer of growth promoter antibiotics in broilers: Pathological and bacteriological studies on intestine

Experimental studies were conducted to evaluate the pathomorphological effect of different combination of organic acids viz. formic acid, propionic acid and lactic acid as a replacer of growth promoter antibiotics. The birds were divided into six equal groups viz. negative control (C₁), positive control (C₂) and treatment groups (%, T₂ T₃ and T₄). Birds of group C₂ were supplied with diet without any antibiotics or acid, group C₂ with Virginiamycin @ 500 gm/100kg feed, group % with 0.3% ammonium formate group T₂ with 0.3% calcium propionate, group T₃ with 0.15% ammonium formate and 0.15% calcium propionate and group T₄ with 0.1% ammonium formate, 0. 1% calcium propionate and 0.1% calcium lactate. Body weight gain was higher in C₂ and C₂ compared with treatment groups in first two weeks, but pathological changes were maximum in negative control, i.e. after 6 weeks, weight gain was significantly better in T₃ and T₄than in groups C₂, % and T₂ groups. Bacteriologically, significant (P<0.01) reduction of E. coli in % and T₄ was evident. Pathomorphological changes in group C₂ and T₂ were maximum. Group C₂ and % showed same types of changes but the changes were less severe in group T₃ and T₄. The most common changes among the groups were thickening of muscular layer, accumulation of inflammatory cells and congested blood vessels. Based on present investigation, it is suggested that combination of organic acid may be used in broiler feed as a replacer of growth promoter antibiotic instead of using only one acid.