1Department of Animal Science and Veterinary Medicine, School of Agriculture and Aquaculture, Tra Vinh University
2Department of Animal Science and Veterinary Medicine, School of Agriculture - Aquaculture, Tra Vinh University
چکیده
Native chicken farming plays an important role in agriculture, and protease enzyme supplementation has been shown to enhance digestion and nutrient absorption. The experiment was conducted on 128 native chickens (5–12 weeks old), arranged in a completely randomized design with four treatments and four replications to assess the effect of protease enzyme supplementation in the diet on growth performance, carcass traits, and hematological characteristics of native chickens. The experimental chickens were fed and given water ad libitum, and the same basal diet was provided to the experimental birds consisting of control diet (the diet without protease) and three different levels of protease enzyme supplementation (0.1, 0.3, and 0.5%). The results showed that the 0.3% protease enzyme supplementation group had significantly (P < 0.05) increased final body weight (1,854 g/bird) and daily weight gain (30.02 g/bird/day) compared with the control group; meanwhile, feed conversion ratio was also significantly improved (P < 0.05). Moreover, carcass weight (1,273 g), breast weight (215.7 g), and thigh weight (155.5 g) exhibited a substantial increase in the 0.3% protease group (P < 0.05) while there was no significant effect on other slaughter characteristics (P > 0.05). However, protease enzyme supplementation had no effect on indices of immune organ, hematological parameters, or liver function including GGT, ALT, AST, and ALP (P > 0.05), apart from a significant difference in liver weight (43.50 g) among treatments. This suggests that the addition of 0.3% protease enzyme can improve the growth performance and carcass quality of indigenous chickens, all without any negative effect on health performance.