Effects of dietary probiotic and protease supplementation on growth performance and carcass yield of Noi crossbred chickens
This study was conducted to evaluate the effects of dietary enzyme protease and probiotic supplementation on the growth performance and carcass yield of Noi crossbred chickens from 4 to 12 weeks of age. A total of 120 Noi cross chicken at four weeks old were allotted in a completely randomized design of four treatments, three replicates, consisting of diets supplemented with NT1 (control), NT2 (g protease/kg feed), NT3 (1g protease + 1g probiotic/kg feed), NT4 (2 g probiotic/kg feed). The experimental diets used were commercial complete feeds corresponding to each growth stage. The results indicated that the supplementation of protease and probiotics did not significantly affect the body weight and body weight gain of the chickens (p>0.05). However, average daily feed intake and feed conversion ratio showed statistically significant differences among treatments (p<0.05). Specifically, the overall average daily feed intake was lowest in NT3 (61.05 g/bird/day) and highest in NT1 (67.03 g/bird/day). Furthermore, the addition of protease and probiotics resulted in a reduction in FCR. Regarding carcass traits, the percentages of breast meat and thigh meat in the supplemented groups were higher than those in the control group. In conclusion, dietary supplementation with protease and probiotics effectively reduced feed intake, improved feed conversion efficiency, and increased breast and thigh meat yields.
