Abstract: This study aims to evaluate the effects of different levels and timings of Broussonetia Papyrifera (BP) leaf supplementation on the production performance and meat quality of yellow-feathered meat chickens, in order to promote the application of BP leaves in yellow-feathered meat chickens. A total of 360 one-day-old yellow-feathered meat chickens were selected and randomly divided into four treatment groups, with six replicates each group. The four treatment groups were fed with a corn-soybean meal-based diet (control group) throughout the entire period (1-63 d), a diet containing 5% BP leaves throughout the entire period (full 5% group), a diet containing 15% BP leaves throughout the entire period (full 15% group), and a diet containing 15% BP leaves in the later period (36-63 d, later 15% group). The results showed that compared with the control group, the body weight and average daily gain of yellow chickens in the full 5% and full 15% groups were significantly reduced (P<0.05), and their feed-to-gain (F/G) ratio was significantly increased (P<0.05), while the production performance of the late 15% group was not significantly different from the control group (P>0.05). Compared with the control group, the yellowness value (b^*) of the pectoral muscle and leg skin of birds in the three BP leave groups was significantly increased (P<0.05), but there was no significant difference in pH, drip loss and shearing force of the pectoral muscle (P>0.05). Compared to the control group, the proportion of monounsaturated fatty acids in the breast muscle of yellow chickens in the BP leaf treatment groups was significantly reduced (P<0.05), and the proportion of polyunsaturated fatty acids was significantly increased (P<0.05). There were no significant differences in the protein or amino acid content of the breast muscle (P>0.05). Additionally, feeding 15% BP leaves in both the full period and the later period significantly increased the content of inosine monophosphate (IMP) in the breast muscle of yellow chickens (P<0.05). In summary, feeding 15% BP leaves during the later stage had no significant impact on the production performance of yellow-feathered meat chickens, but it can increase the yellowness value of the breast muscle and skin, enhance the proportion of polyunsaturated fatty acids in the breast muscle, and increase the content of IMP, thus having an improving effect on the quality of the muscle.

Key words: yellow-feathered chicken, Broussonetia Papyrifera leaf, unconventional feed material, production performance, meat quality