Rice Bran as a Sustainable Feed Material Substitute to Improve the Meat Quality in Late-Stage Wenchang Chicken

The growing competition between humans and livestock for corn-soybean based feed calls for sustainable alternatives like rice bran. This study assessed substituting feed with rice bran (0%, 5%, 10%, 15%, 20%) in diets for slow-growing Wenchang chickens, a prized Chinese yellow-feathered breed. Up to 15% substitution maintained final body weight and average daily gain, but 20% substitution reduced body weight. Feed intake rose significantly at 10–20% substitution. Substituting 15–20% rice bran for feed significantly reduced abdominal fat without affecting slaughter performance or serum biochemical indicators. Meat quality had trade-offs: thigh muscle redness improved at 15%, and breast muscle fibers changed, but water-holding capacity decreased with increased cooking loss. Breast muscle intramuscular fat and inosinic acid increased, while fatty acid profiles changed, reducing both beneficial (e.g., oleic acid) and undesirable trans fatty acids at ≥10%, and saturated fatty acids in thigh muscle at 15%. Moreover, in the 20% group, alanine and glycine levels in breast muscles were notably lower than in the control and 5% groups. Additionally, the 15–20% group showed a significant reduction in total amino acids, the 10–20% group showed a significant reduction in flavor amino acids, and various free amino acids in thigh muscles were also reduced compared to the control group. Rice bran affected meat quality and nutrition, with mixed effects. Notably, incorporating a 10% rice bran substitute in the diet can improve meat quality traits in slow-growing yellow-feathered broiler chickens without impacting production performance.