Dermatophytes and keratinophilic fungi in cats and dogs.

During an 11 month period from January to November 1987, dermatophytes and keratinophilic fungi were isolated from 70 (75%) of 93 cats and 62 (36.9%) of 168 dogs. The most common isolate was Microsporum canis from 54 (58%) cats and 33 (19.6%) dogs, followed by Trichophyton mentagrophytes from 5 (5.4%) cats and 9 (5.3%) dogs, Aphanoascus fulvescens (4 cats and 9 dogs), M. gypseum (5 dogs), Tr. terrestre (3 dogs) Myceliophthora vellerea (2 dogs) and Chrysosporium indicum, Chr. merdarium and Chr. tropicum from cats. Alternaria, Scopulariopsis, Penicillium, Cladosporium, Aspergillus and Acremoniumspp., in descending frequency, were the most commonly found fungi in cats and dogs. The frequent infestation by the mite Tyrophagus putrescentiae on M. canis cultures suggest that mites may play a part in the carriage of fungi among animals. This mycophagous mite could disperse the fungi in animal hair by way of their fecal pellets during a transitory infestation. In this instance, the female mite can lay eggs and these could hatch on the animal's hair or in Petri dishes in which hair samples are cultured. In this event the future prospects of animal prophylaxis against dermatophytes could be made more effective by the regular use of acaricide agents on animal hair.