Field study examining the mucosal microbiome in equine glandular gastric disease.

Equine glandular gastric disease (EGGD) is a common disease among athletic horses that can negatively impact health and performance. The pathophysiology of this EGGD remains poorly understood. Previous studies using controlled populations of horses identified differences in the gastric glandular mucosal microbiome associated with disease. The objective of this study was to compare the gastric microbiome in horses with EGGD and those without across multiple barns and differing management practices. We hypothesized that alterations in the microbiome of the gastric glandular mucosa are associated with EGGD. A secondary objective was to perform a risk factor analysis for EGGD using the diet and management data collected. Microbial populations of biopsies from normal pyloric mucosa of horses without EGGD (control biopsies), normal pyloric mucosa of horses with EGGD (normal biopsies) and areas of glandular mucosal disruption in horses with EGGD (lesion biopsies) were compared. Lesion biopsies had a different microbial community structure than control biopsies. Control biopsies had a higher read count for the phylum Actinomycetota compared to lesion biopsies. Control biopsies also had an enrichment of the genera Staphylococcus and Lawsonella and the species Streptococcus salivarius. Lesion biopsies had an enrichment of the genera Lactobacillus and Actinobacillus and the species Lactobacillus equigenerosi. These results demonstrate differences in the gastric glandular microbiome between sites of disrupted mucosa in horses with EGGD compared to pyloric mucosa of horses without EGGD. Risk factor analysis indicated that exercise duration per week was a risk factor for EGGD.

Dietary and management factors influence the equine gastric microbiome.

OBJECTIVE: The purpose of this study was to characterize the relationship of diet and management factors with the glandular gastric mucosal microbiome. We hypothesize that the gastric mucosal microbial community is influenced by diet and management factors. Our specific objective is to characterize the gastric mucosal microbiome in relation to these factors. ANIMALS: 57 client-owned horses in the southern Louisiana region with and without equine glandular gastric disease. PROCEDURES: Diet and management data were collected via a questionnaire. Gastroscopy was used for evaluation of equine gastric ulcer syndrome and collection of glandular mucosal pinch biopsies. 16S rRNA amplicon sequencing was used for microbiome analysis. Similarity and diversity indices and sequence read counts of individual taxa were compared between diet and management factors. RESULTS: Differences were detected in association with offering hay, type of hay, sweet feed, turnout, and stalling. Offering hay and stalling showed differences in similarity indices, whereas hay type, sweet feed, and turnout showed differences in similarity and diversity indices. Offering hay, hay type, and sweet feed were also associated with differences in individual sequence read counts. CLINICAL RELEVANCE: This study provides preliminary characterization of the complex relationship between the glandular gastric microbiome and diet/management factors. The ideal microbiome to promote a healthy glandular gastric environment remains unknown.

Effects of a Supplement Containing Cannabidiol (CBD) on Sedation and Ataxia Scores and Health.

Supplements containing Cannabidiol (CBD) are available for horses, however, few studies have been published on their effects on behavior and health parameters. The purpose of this study was to determine if a daily oral supplement containing CBD would cause sedation, ataxia or alterations in other health parameters during administration for 56 days. Twenty clinically healthy adult Thoroughbred horses were housed in stalls. Before treatment was initiated, a complete physical examination, complete blood count (CBC) and biochemical panel were evaluated. In addition, horses were examined for sedation and ataxia using standard scoring systems. Horses were randomly divided into two treatment groups, treated (supplement pellets containing CBD as Hemp Extract, 150 mg) or control (supplement pellets without CBD). Horses were treated daily and sedation and ataxia scores were assigned by two masked observers once weekly for 56 days. Horses were monitored daily for clinical signs or adverse events and body weights were recorded weekly. A CBC and biochemical panel were repeated on days 28 and 56, two hours after administration of the supplement. The supplement was readily consumed by the horses and no adverse effects were seen over the treatment period. Sedation and ataxia scores ranged from zero to two for all horses during the weekly examinations and there was no statistical difference between treatment groups. There were no treatment effects on blood values, including indicators of anemia and blood proteins, liver enzymes, kidney values, electrolytes or calcium. Body weight significantly increased in all horses, by Day 56 compared to Day zero but no treatment by day effect was noted. The CBD supplement (150 mg) was readily consumed and safe and did not result in changes in mentation, gait, or other health parameters, and no adverse clinical signs were observed during 56 days of oral administration.