The fungal flora of the hair and underlying skin from 2 sites was examined qualitatively in 20 horses free of skin or ocular disease. Fungi were isolated from both the hair and the underlying skin of all 20 horses. Twenty-two genera regarded commonly as saprophytes were identified and an additional 2 fungi resembled the perfect state of the cutaneous pathogenic genera Microsporum and Trichophyton. Cladosporium spp, Penicillium spp, and Rhizopus spp were the most frequently isolated saprophytes. In general, similar fungi were isolated from the hair and underlying skin, and differences were not noted in isolates from the saddle and rump regions.

During a 1-year period, specimens were obtained monthly from 5 hair coat and 7 mucous membrane sites of 11 healthy dogs. Among 804 isolates of staphyloccocci, 13 species were identified. Staphylococcus intermedius was the most frequently isolated (40.2% of total isolates) coagulase-positive species, and S xylosus was the most frequently isolated (17.3%) coagulase-negative species. Moreover, S intermedius was the most frequently isolated species from the 12 sites evaluated and was isolated persistently from 8 of the 9 dogs that completed the 1-year study. On the basis of a commerical identification system, 14 profile numbers were identified for isolates of S intermedius. However, 2 profile numbers accounted for a majority (70.9%) of the isolates. Specific S intermedius biotypes identified on the basis of hemolysis, coagulase production, beta-lactamase activity, and antimicrobial susceptibility patterns were found repeatedly in 3 dogs. Seemingly, S intermedius was a resident of the normal bacterial microflora of these dogs; however, the inability to isolate S intermedius from 1 dog during the study year indicated that not all dogs habor S intermedius as a resident microorganism.

Microorganisms from normal eyes of hospitalized and stabled horses were identified, and the frequency of isolation was compared between the 2 groups. Using standard techniques, swab specimens from both eyes of 22 hospitalized horses and both eyes of 18 stabled horses were cultured for aerobic bacteria and fungi. Ninety-six aerobic bacteria and 57 fungi were isolated. The predominant bacterial isolates were gram-positive organisms, most of which belonged to the genera Corynebacterium, Bacillus, Staphylococcus, and Streptomyces. Gram-negative organisms comprised less than one-fourth of the bacterial isolates, with the genera Neisseria, Moraxella, and Acinetobacter being the most commonly isolated. Environmental fungi Cladosporium and Alternaria accounted for half of all fungal isolates. In only 5 horses were fungi isolated without accompanying isolation of bacteria. The frequency of isolation of fungi was higher (P less than 0.01) in stabled horses. For bacteria, the frequency of isolation was higher (P less than 0.08) in male horses. Results of susceptibility testing were recorded as the percentage of all isolates were highly susceptible to a given antimicrobic drug. Bacterial isolates were highly susceptible (greater than or equal to 90%) to neomycin, polymixin B, gentamicin, and chloramphenicol. Overall, filamentous fungi had highest susceptibility to natamycin (97%). Miconazole was highly efficacious (100% susceptibility) against Fusarium and Aspergillus.