Abstract:

The experiment aims to investigate the effects of low protein diets on growth performance, carcass quality, and meat quality of yellow feather broilers. In this study, 360 1-day-old slow-growing hens were selected, and a control group and an experimental group were set up. Each group had 6 replicates, with 30 chickens per replicate. The crude protein concentration in the diet of the experimental group at stages 1-6 weeks, 7-13 weeks and 14-19 weeks was set at 90%, 95% and 100% of the control group, respectively. The formula increased the proportion of corn by-products and reduced the dosage of soybean meal and soybean oil. The results showed that compared with the control group, body weight of the experimental group significantly decreased at all stages (P<0.05), weight gain decreased at 1-6 weeks (P<0.01), and feed to gain ratio increased (P<0.01). There was no significant change in the whole feed to gain ratio (P>0.05). The abdominal fat rate of chickens significantly decreased (P<0.05), and the color of chest muscle about a value and L value were better than those of the control group (P<0.05). The daily crude protein required for unit weight gain decreased by 1.7%, and the feed cost decreased by 7.1%. In summary, under the conditions of this study, downregulating the crude protein concentration in the early and middle growth diets significantly reduced the overall growth rate of yellow feathere broilers, but it could save weight gain feed costs and have a certain improvement effect on carcass quality and meat quality.

Key words: low protein diet, yellow feather broiler, growth performance, carcass quality