Effect of encapsulated Averrhoa carambola L. leaf extract on the growth performance, haemato-biochemical parameters, gut health, and antioxidant activity in broiler chickens

This study aimed to evaluate the effect of encapsulated <i>Averrhoa carambola</i> L<i>.</i> leaf extract (EAC) as a phytobiotic feed additive on the growth performance, haemato-biochemical parameters, gut health, and antioxidant activity in broiler chickens. A total of 280 one-day-old chicks were allocated to four treatments with seven replicates and 10 broilers per replicate (CON: control group/basal diet; EAC1: basal diet supplemented with 500 mg/kg EAC; EAC2: basal diet supplemented with 1000 mg/kg EAC; EAC3: basal diet supplemented with 1500 mg/kg EAC. Growth performance was significantly enhanced (<i>P</i> < 0.05), as evidenced by increased body weight gain (days 15-21) and feed efficiency (days 15-35) in all treatment group compared with the control group. Haemato-biochemical parameters were positively influenced, with leukocytes and lymphocyte levels being significantly lower (<i>P</i> < 0.05) in the EAC2 group than in the control group. The uric acid concentration was significantly reduced (<i>P</i> < 0.05) in EAC1 and EAC3 groups compared to the control group. Gut health indicator improved, including the relative weight of the small intestine, liver, abdominal fat, length of duodenum and jejunum, weight and length ratio of the jejunum and ileum, ileum crypt depth, and lactic acid bacteria count in the ileum, were significantly higher (<i>P</i> < 0.05) in the EAC1 group than in the others groups. In conclusion, the encapsulated <i>Averrhoa carambola</i> L. leaf extract is beneficial for enhancing growth performance, haemato-biochemicals parameters, and gut health in broiler chickens.