Effects of dietary mangosteen peel powder and extract on the growth performance, meat quality and indicators for immunity, gut health and antioxidant activity in broiler chicks

The objective of this study was to evaluate the effects of dietary mangosteen peel preparations, either powdered (MspP) or ethanolic extract (MspE), on the growth performance, meat quality, immune response, gut health, serum biochemical profiles, and antioxidant activity of broiler chicks. A total of 480 day-old straight-run broiler chicks (Ross 308) were randomly placed into four treatments, with eight replicates of 12 chicks each, and subjected to one of the four experimental diets for 21 days. The corn and soybean meal-based diet was supplemented with 2% MspP (20 g per kg of diet) or 0.05% and 0.1% MspE (0.5 g and 1.0 g per kg of diet). Data were analyzed using analysis of variance, and post hoc comparisons of treatments were performed using Tukey's Honestly Significant Difference test. From days 0 to 21, dietary mangosteen peel preparations did not affect growth performance (body weight gain, feed intake, and feed conversion ratio), thigh meat and tibia characteristics, serum markers of innate immunity (interferon-r, interleukin-10, alpha-1-acid glycoprotein, and nitric oxide), and ileal morphology in broiler chicks (P > 0.05). Dietary mangosteen peel preparations increased the percentage of high-density lipoprotein cholesterol and decreased the relative concentrations of isobutyrate and branched-chain fatty acids in the cecal digesta compared with the control chickens. Notably, dietary mangosteen peel preparations altered the antioxidant characteristics of the serum, liver, and thigh meat. Dietary MspE increased glutathione peroxidase (P = 0.039) in the serum and catalase in the serum (P = 0.008), liver (P = 0.05), and thigh meat (P = 0.01) compared to the control group. In addition, dietary MspP increased catalase levels in thigh meat compared to those in the control diet-fed chickens (P = 0.01). The concentration of malondialdehyde, an indicator of lipid peroxidation, was lower in all chicks-fed diets containing mangosteen peel preparations; however, statistical significance was only noted in the serum samples (P < 0.0001). Collectively, our study shows that dietary mangosteen peel preparations are potent natural antioxidants that can be used as functional dietary additives to effectively mitigate oxidative stress in broiler chicks.