Dietary Supplementation Changes Gut Microbiome and Urinary VOCs in Male Asiatic Black Bears Influencing Female Mate Choice Preferences

Chemosensory cues inform mammalian mate selection by signaling genetic quality, social status, and reproductive fitness. Gut microbiota impact host odor through the metabolic regulation of volatile organic compounds (VOCs), but effects on chemosensory-driven mate choice remain underexplored. Here we supplemented the diets of two groups of captive male Asiatic black bears (U. thibetanus) with either antibiotic (Anti-treated, n = 10) or dietary supplement yeast tablets (DS-treated, n = 10). Urine and fecal samples were collected concurrently before and after the treatment. Urinary VOCs were analyzed using GC-MS, while gut microbiome community structure was assessed via 16S rRNA sequencing. In male DS-treated bears, the relative abundance of Sarcina and Vagococcus bacteria declined significantly (P