First insights into the physiological status and gut microbiota of free-grazing Tibetan goats in Kangding, Western China.

Objectives: This study assessed the health status, morphometric traits, and gastrointestinal microbiota of Tibetan goats reared under traditional free-range conditions in Kangding, western China, without antibiotics, anthelmintics, or vaccinations. Materials and Methods: Five adult Tibetan goats were assessed for body weight, linear measurements, and blood parameters. Microbial communities from six gut segments of the gastrointestinal tract were characterized using 16S rRNA gene sequencing. To examine seasonal dynamics, rectal fecal microbiota from eight additional goats, sampled during winter and summer, were compared. Results: Despite fluctuating forage availability, growth traits were comparable to those reported for established meat goat breeds. Most hematological and serum biochemical values fell within normal physiological ranges, though mild deficiencies in certain minerals were observed, accompanied by geophagic behavior. The gut microbiota exhibited clear spatial structuring along the digestive tract, with Firmicutes and Bacteroidota as the dominant phyla and higher microbial richness in the hindgut. Seasonal differences were evident in the rectal fecal microbiota, with higher relative abundance of Escherichia-Shigella in winter and increased levels of Prevotella and the Christensenellaceae_R-7_group during summer. Functional predictions suggested greater nutrient transport and signaling capacity in the small intestine, whereas the hindgut showed stronger metabolic activity, particularly in fermentation-related pathways. Conclusions: Tibetan goats demonstrate notable physiological and microbial adaptability under extensive management. However, seasonal nutritional constraints may pose subclinical health risks. Integrating routine monitoring of physiological and microbial indicators could help safeguard animal welfare, maintain meat quality, and support the long-term sustainability of traditional pastoral systems in this region.