Feeding combination of synthetic carotenoids improved performance, immune response and blood biochemical profiles in heat stressed broilers

摘要

A biological study was conducted in newly hatched (200) broiler chicks (44.06 +/- 2.18 g) divided into 5 treatments each consisting of 4 replicates with 10 birds in each, were fed with control (basal diet), T-1 (canthaxanthin (CAN) and apocarotenoid (APO) at 25 ppm each), T-2 (CAN 50 and APO 25 ppm), T-3 (CAN 25 and APO 50 ppm) and T-4 (50 ppm each). Birds were reared for 42 days under standard managemental conditions during hot-dry summer season with THI 84.66. Bi-weekly body weight (BW) and feed intake (FI) were recorded. Blood samples were collected and shank colour was measured at 28th and 42nd days of age. Cell mediated immune response and carcass characteristics were studied at 28 and 42 days of age respectively. Overall BW and body weight gain (BWG) were significantly higher in birds fed with combination of 25 ppm CAN and APO compared to other groups. BWG was significantly higher in T-1 than other treatment and control groups at finisher phase. Feed conversion efficiency (FCE) was significantly improved in T-1 and T-2 than all other groups. Dietary inclusion of synthetic carotenoids significantly increased the aspartate transaminase, phosphorus and total protein but reduced cholesterol and triglyceride level in blood plasma compared to unsupplemented dietary treatment group. Higher pigmentation was observed in T-1 than the other combinations of carotenoids. It could be concluded that feeding combination of synthetic carotenoids (CAN and APO) at 25 ppm each exhibited positive effect on performance, blood parameters and pigmentation in heat stressed broilers.