Yuhong Wu

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.

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.

This study investigated the cyathostomin species composition, anthelmintic efficacy, and potential resistance-associated mutations in Chinese grazing horses. Fecal samples were collected from 90 adult horses. Fecal egg counts (FECs) were determined using a modified McMaster method. Third stage larvae (L3) cultured from the eggs were identified to species level by PCR amplification and sequencing of the internal transcribed spacer-2 (ITS-2). The main species included Cylicocyclus nassatus and Cylicostephanus spp. However, differences in the relative abundance of less common species, including Cyathostomum pateratum and Cylicocyclus ashworthi, suggests regional variation. Anthelmintic efficacy was assessed by a fecal egg count reduction test (FECRT) following albendazole administration. Mutations at six codons of the β-tubulin iso-type-1 (tbb-iso-1) gene were screened by gene sequencing. The results showed that, despite harboring an abundant and diverse cyathostomin community, this herd remained susceptible to albendazole. Overall, this study provides baseline data on cyathostomin species composition and anthelmintic susceptibility in horses from China, contributing to global surveillance of equine cyathostomin resistance.

Objectives: This study aimed to assess left atrial (LA) size in healthy cats using cardiovascular MRI (cMRI) and to compare this with LA size assessed by two-dimensional echocardiography. The hypothesis was that cMRI would accurately determine LA size in domestic cats. Methods: A prospective comparative study was performed. Six healthy cats were selected for the study. Standard two-dimensional echocardiography was performed with and without general anaesthesia. cMRI was conducted under general anaesthesia. A comprehensive analysis of LA mass and function measurements was performed to determine the consistency and correlation of LA size and function indicators between two-dimensional echocardiography and cMRI. Results: Our study found that intraobserver variability for cMRI measurements was lower than that for two-dimensional echocardiography. Compared with cMRI, echocardiography under anaesthesia significantly overestimated maximal LA volume (LAVmax_2D, P <0.01) and significantly underestimated minimal LA volume (LAVmin_2D, P <0.01). The LAVmin measured by two-dimensional echocardiography exhibited the highest consistency (intraclass correlation coefficient = 0.857) and correlation ( R = 0.75, P <0.01) with LAVmin measured by cMRI. The linear regression equation was LAVmin_ cMRI = 0.891 × LAVmin_2D + 0.304. Conclusions and relevance: cMRI represents a reproducible method for assessing LA mass in domestic cats. This study underscored the importance of echocardiography in veterinary cardiology, and the LAVmin measured by two-dimensional echocardiography may reflect the true LAVmin.

The gastrointestinal microbiota develop alongside the host and play a vital role in the health of cecal fermenters such as chinchillas. However, little is known about the microbiota architecture in healthy chinchillas. Illumine-based 16S rRNA gene amplicon sequencing was used to investigate the microbiota present in six different gastrointestinal tract regions of three healthy adult chinchillas. The findings revealed significantly more abundant microbiota in the large intestine compared with the proximal segments. In addition, the cecum exhibited better evenness compared to the colon. The core microbiota are Firmicutes, Bacteroidota, Actinobacteriota, and Proteobacteria at the phylum level. The signature microbiota of each segment were identified. The cecum had 10 signature microbiota, which had the widest coverage and overlapped with that of the cecum. The stomach had five signature microbiota, exhibiting the second widest coverage and overlapping with the duodenum. No signature microbiota were detected in the jejunum and ileum. While similarities exist with the microbiota of other cecal fermenters, chinchillas exhibit distinct microbiota closely related to their unique digestive mechanisms. This study is a preliminary study of the gastrointestinal microbiota architecture and distribution in healthy chinchillas. Further study is needed in order to better understand the effect of gastrointestinal microbiota on the health of the chinchilla.