Effects of dietary mulberry anthocyanins on meat quality, antioxidant capacity, gut microbiota, and plasma anthocyanin exposure in North China Chai chickens

Abstract

Chicken is the second most consumed meat in China after pork and represents an important source of animal protein. Late-laying hens are a major by-product of the egg industry, but their meat quality often declines after prolonged egg production, limiting their economic value. Mulberry (Morus alba L.) is rich in anthocyanins with antioxidant, anti-inflammatory and lipid-lowering effects, offering potential application in improving the meat quality of spent hens. This study aimed to evaluate the effects of dietary mulberry anthocyanins(MA) on slaughter performance, serum biochemical indices, antioxidant status, meat quality, cecal microbiota and plasma exposure to major anthocyanins in late-laying North China Chai chickens. A total of 240 healthy 370-day-old chickens were randomized into five groups: a basal diet control (Con) and four diets supplemented with MA at 50, 100, 200, or 400 mg/kg (MA_50, MA_100, MA_200, MA_400) for 30 days. The results showed that dietary MA increased dressing percentage and thigh muscle yield, while decreasing serum TG, ALT and AST levels compared with Con (P < 0.05). Antioxidant indices were improved, with increased T-AOC, T-SOD, glutathione peroxidase (GSH-Px) and catalase (CAT), accompanied by reduced malondialdehyde (MDA) (P < 0.05). Regarding meat quality, MA reduced cooking loss, crude fat content, and thiobarbituric acid reactive substances (TBARS), while increasing redness (a*), crude protein, moisture, myoglobin, and collagen contents (P < 0.05). 16S rRNA sequencing indicated that MA altered cecal microbial community structure and increased the relative abundance of potentially beneficial taxa. In a separate oral gavage experiment (1,500 mg/kg), cyanidin-3-O-glucoside (C3G) and cyanidin-3-O-rutinoside (C3R) were detectable in plasma at 15 min post-gavage, peaked at approximately 30 min, and declined to undetectable levels by 24 hours. Collectively, dietary MA improved antioxidant status and selected meat quality traits, and modulated gut microbiota in late-laying North China Chai chickens. These findings underscore the potential of MA as a natural feed additive for improving the utilization value of late-laying hens.