Dietary Black Soldier Fly Larvae Meal Improves Growth Performance and Meat Quality Associated with Enhanced Antioxidant Capacity and Intestinal Health in Wenchang Chickens

Wenchang chicken, a premium indigenous yellow-feathered broiler in China, faces production constraints due to high feed costs and soybean meal dependence. Black soldier fly larvae meal (BSFLM) is a promising alternative protein source, but its effects on Wenchang chickens are largely unknown. This study evaluated the effects of dietary BSFLM on growth performance, meat quality, intestinal health, and cecal microbiota. A total of 192 fifty-day-old female Wenchang chickens were randomly assigned to diets with 0%, 5%, 10%, or 15% full-fat BSFLM for 42 days. The 15% BSFLM inclusion increased final body weight (p < 0.05) while reducing the feed conversion ratio (p < 0.01) and feed cost per kg gain (p < 0.001). Regarding meat quality, 15% BSFLM enhanced redness (a*) and reduced shear force, 48 h drip loss, and cooking loss (p < 0.05). It also elevated antioxidant enzyme activities, upregulated Nrf2–Keap1, improved intestinal villus architecture and tight junction proteins, and reduced serum diamine oxidase (p < 0.05). Cecal microbiota underwent distinct restructuring, with dose-dependent proliferation of beneficial taxa. Overall, BSFLM exerts beneficial effects on the feed efficiency, meat quality, and intestinal health of Wenchang chickens, and the 15% inclusion level achieved relatively better comprehensive outcomes. This study provides a scientific reference for insect protein utilization and contributes to sustainable high-quality Wenchang chicken production.