Supplementation of lactic and citric acid in antibiotic free diets and their influence on performance, meat yield and immune response of broiler chickens

The present study aimed at evaluating two organic acids, lactic acid (LA) and citric acid (CA), each at 1.0 and 2.0% levels for replacing antibiotic (AB-Virginiamycin 11 mg/kg) in diets. In a feeding trial with 270 broiler chicks (Vencobb) LA and CA were tested in 2 x 2 factorial design, and compared with AB and control diets from day-one to 42 d of age in battery cages. Each of the 6 test diets was offered to 9 replicates of 5 chicks, and their growth performance, carcass attributes, bone morphology and immune response were recorded. Supplemental LA or CA at 2% level in diets significantly (p<0.01) enhanced body weight (2109–2195 g) compared to AB and Control (1960–1995 g). The improvement in weight gain with organic acids was 9.6–10.9% over the control and 7.75–8.9% over AB diets. Both the organic acids reduced feed intake, which coupled with higher weight gain produced better FCR compared to AB diet. LA inclusion in diets recorded higher meat yields (>3.1%) and breast meat yield (>9.7%) with desirable decline in abdominal fat. LA even at 1% level supported higher tibia weight (5.96 g), length (8.11 cm) and low leg scores (1.08), indicating better bone condition. LA and CA at 2% level improved immune competence in broilers measured as humoral and cell mediated response, compared to the AB and control diets. It is concluded that LA and CA supplementation at 2% level improved the broiler performance, meat yields, bone conformation and immune response over AB and control diets, implying that organic acids could replace antibiotic from broiler diets effectively and beneficially.