SEASONAL STUDY OF THE FUNGAL BIOTA OF THE FUR OF DOGS

During a one year period, 944 dogs from the Municipal kennel of Barcel ona were examined to detect animals with suspected dermatophytosis. On ly a few animals (1.8%) presented skin lesions but none of them had de rmatophytosis. A representative number of dogs without visible skin le sions (n = 172), selected at random, were used to carry out a seasonal study of the mycobiota of their fur. Fifteen isolates belonging to th e genera Microsporum and Trichophyton were isolated from 14 of the 172 (8.1%) dogs without lesions. The identity of these fungi was Microspo rum gypseum (6/15), Trichophyton terrestre (4/15), M. canis (2/15), M. cookei (2/15) and Trichophyton ajelloi (1/15)(one strain each of M. g ypseum and T. ajelloi were isolated from one dog). Species of Penicill ium (% prevalence = 89.5%), Alternaria (86.6%), Cladosporium (84.9%), Aspergillus (77.3%), Scopulariopsis (65.7%) and Chrysosporium (64.5%) were the most prevalent. No significant differences in the fungal biot a were observed with respect to age, gender, hair length or between mi xed and pure breed dogs. A large number of isolates, including species belonging to the genera Beauveria, Chrysosporium, Malbranchea and Sco pulariopsis, that macroscopically and/or microscopically resemble derm atophytes and may be mistaken for them, produced a red color change in Dermatophyte Test Medium. No significant seasonal difference was dete cted among the isolates belonging to the the most frequently encounter ed genera, with the exception of Scopulariopsis (higher in summer and autumn) and Chrysosporium (higher in summer). Species from other gener a, with lower occurrence also presented significant differences in the ir seasonal distribution. Arthrinium, Aureobasidium, Chaetomium and Ph oma spp. presented maximum prevalence peaks in spring, Fusarium, Paeci lomyces, Phoma and Rhizopus spp. in summer and Geotrichum and Mucor sp p. in autumn. The Microsporum and Trichophyton species were more frequ ently isolated in summer.