Bacteria and Fungi on the Surface and Within Noninflamed Hair Follicles of Skin Biopsy Specimens From Horses With Healthy Skin or Inflammatory Dermatoses

The study conducted a retrospective analysis using light microscopy to evaluate the presence of bacteria and fungi on the surface and within noninflamed hair follicles in skin biopsy specimens from 247 horses with inflammatory dermatoses and 27 horses with healthy skin. It was found that cocci were present on the surface of specimens from 23% of horses with skin disease and 7% of horses with healthy skin. Bacterial folliculitis showed a higher prevalence of surface bacteria (57%) compared to other dermatoses, which had a prevalence of less than 30%. There was a significant correlation between the presence of surface cocci and the degree of epidermal hyperkeratosis. Cocci were found in the keratin of noninflamed hair follicles in only 2% of horses with skin disease and none in healthy horses. Fungal poroconidia were detected on the surface of 4% of horses with skin disease, while yeasts were not found in any samples.