Objective: This study aimed to evaluate the effects of garlic skin as a feed ingredient on growth performance, antioxidant capacity, immune function, and rumen health in goats.Methods: Twelve male black goats with similar body conditions were randomly...
Objective: This study aimed to evaluate the effects of garlic skin as a feed ingredient on growth performance, antioxidant capacity, immune function, and rumen health in goats.Methods: Twelve male black goats with similar body conditions were randomly assigned to two groups. The control group (CON) was fed a basal diet, while the experimental group (GAS) received a diet supplemented with garlic skin for 60 days.Results: Results showed that goats' final weight and average daily gain significantly increased in the GAS group compared to the CON group (p<0.05). The GAS group exhibited enhanced activities of total superoxide dismutase, glutathione peroxidase, catalase, and higher total antioxidant capacity levels, while malondialdehyde content significantly decreased (p<0.05). Immunoglobulin A and immunoglobulin G levels were significantly elevated, along with increased concentrations of anti-inflammatory cytokines interleukin-4 and interleukin-10, whereas pro-inflammatory cytokines interleukin-1β, interleukin-6, and tumor necrosis factor-α were significantly reduced (p<0.05). The rumen fluid of GAS group showed significant increases in ammonia nitrogen, acetate, propionate, and total volatile fatty acids, with a reduction in the acetate-to-propionate ratio (p<0.05). Significant improvements were also observed in rumen papilla height, width, and density (p<0.05). 16S rDNA analysis revealed enhanced microbial diversity and enrichment of functional bacterial groups, such as Firmicutes and Christensenellaceae_R-7_group, involved in fiber degradation and volatile fatty acid production. Key metabolites, including 5-methylthioribose and glucose 6-phosphate, were positively correlated with growth and antioxidant capacity.Conclusion: In conclusion, garlic skin supplementation enhanced antioxidant and immune function, optimized rumen fermentation, improved microbial composition, and promoted goat health and productivity.