Barnesiella viscericola mediates uric acid homeostasis as a keystone taxon of the goose gut microbiome

Goslings are economically important poultry, yet they are susceptible to gout and hyperuricemia. The gut microbiota profoundly affects host nutrition, metabolism, and immunity. Here, we established a high-protein diet-induced hyperuricemia model in four goose breeds (Huoyan, Shitou, Yangzhou, and Sichuan White) and performed metagenomic analysis of their cecal microbiota. We identified a core-predominant gut microbe, Barnesiella viscericola (BV), shared across breeds. Oral administration of live BV to Shitou goslings significantly reduced serum uric acid by inhibiting xanthine oxidase activity and expression and downregulating intestinal GLUT9 expression, thus suppressing uric acid production and reabsorption. Under normal conditions, BV promoted weight gain, increased lung and spleen indices, enhanced cecal tight junction protein ZO-1 expression, and exhibited no hepatorenal toxicity. These findings offer a novel perspective for preventing gosling gout by targeting the gut microbiota and reveal the functional contribution of a shared core microbe to hyperuricemia alleviation.