The equine gastrointestinal microbiome plays an essential role in digestion, energy metabolism, immune regulation, and maintenance of intestinal homeostasis. Increasing evidence suggests that microbial-derived metabolites provide a functional link between diet, the microbiome, and host physiology. This narrative review summarizes current knowledge on how dietary factors, including structural carbohydrates, non-structural carbohydrates, protein, and lipids, influence microbial function and metabolite production in horses. Relevant publications available up to June 2026 were identified through searches of PubMed, Web of Science, Scopus, and Google Scholar and were narratively synthesized according to dietary factors, microbial metabolites, associated diseases, and nutritional interventions. Emphasis is placed on major microbial metabolites, including short-chain fatty acids, endotoxins, bile acid derivatives, tryptophan metabolites, and nitrogenous fermentation products, and their potential roles in health and disease. Current evidence supports a central role for the nutrition–microbiota–metabolite axis in gastrointestinal disorders such as colic, colitis, equine gastric ulcer syndrome, and carbohydrate-associated laminitis, whereas its involvement in equine metabolic syndrome and the gut–lung axis remains less well defined. The review also discusses microbiome-targeted nutritional interventions and emerging multi-omics approaches that are improving our understanding of microbial function. Collectively, these findings highlight the potential of microbiome-informed nutritional strategies to support equine health, welfare, disease prevention, and athletic performance.

Mare’s milk and fermented mare’s milk are potential sources of yeasts for probiotic screening. This study evaluated the in vitro probiotic potential of 23 yeast isolates from these sources. MALDI-TOF MS preliminarily identified 15 isolates as Kluyveromyces marxianus, four as Pichia manshurica, two as Pichia fermentans, one as Saccharomyces cerevisiae and one as Yarrowia lipolytica. Stress tolerance, solvent affinity, autoaggregation, coaggregation, hemolytic activity, and cell-free supernatant-mediated antibacterial activity were assessed. Relative viable counts, calculated against corresponding controls at the same 4-h endpoint, averaged below 6% under 0.3% bile salt exposure and below 1% at pH 2. Responses at pH 3 and elevated temperatures were variable. Solvent affinity ranged from 2.50% to 95.07%, with differences among isolates within each solvent (all p < 0.001). Autoaggregation ranged from 7.50% to 95.40% after 4 h. Coaggregation reached approximately 55% with Escherichia coli, 49% with Salmonella Enteritidis, and 50% with Staphylococcus aureus. Supernatants from 10 isolates inhibited at least one indicator bacterium, and six inhibited all three. R3-4 produced the numerically largest mean inhibition zone against S. aureus (19.3 ± 1.2 mm). No detectable hemolysis was observed. An exploratory five-domain score highlighted R3-4 (putative Y. lipolytica) and four putative K. marxianus isolates, without indicating superiority across all traits. These phenotypic profiles inform further screening, molecular confirmation, comprehensive safety assessment, and equine-relevant functional validation remain necessary.

This study aimed to evaluate the therapeutic effects of platelet-rich plasma (PRP) and Cervus and Cucumis polypeptide (CCP) injections in rats with post-traumatic osteoarthritis (OA). The model was established by transection of the anterior cruciate ligament, and the animals were subsequently treated with PRP and CCP. Articular cartilage degeneration was assessed through gross morphological observation, histopathological staining, and a standardized scoring system. Concurrently, pain-related behaviors, joint swelling, levels of inflammatory cytokines, and markers associated with extracellular matrix degradation were measured. The results demonstrated that, compared with the OA model group, PRP and CCP exhibited varying degrees of functional improvement, specifically, a reduction in pain-related behaviors and an alleviation of joint swelling. Furthermore, cartilage morphological damage was diminished, inflammatory marker levels decreased, and indicators of extracellular matrix degradation were attenuated. Histopathological examination of liver and kidney tissues revealed no apparent abnormalities. This study provides valuable experimental evidence for further treatment strategies for OA.