Fungal flora of the haircoat of cats with and without dermatophytosis.

In catteries with a long-standing problem of dermatophytosis, Microsporum canis was the sole fungal isolate from all cats, regardless of clinical signs. Fungal isolates from cats in catteries with an early problem of M. canis infection (less than 30 days) consisted of M. canis mixed with saprophytic fungi, fewer cats with pure M. canis cultures and individual cats that were culture negative for M. canis. When these catteries were resampled at a later date, M. canis was the only fungus isolated from all cats. In catteries with no history of dermatophytosis, M. canis was never isolated and the fungal isolates were similar to those found previously in pet cats. No significant differences in age, sex, or hair length was found between the M. canis-infected and M. canis-free cats.