MATING TYPES OF THE MICROSPORUM-GYPSEUM COMPLEX ISOLATED FROM ANIMALSIN ITALY

Background and objective. Microsporum gypseum is a common saprophyte o f the soil and an occasional causative agent of human and animal derma tophytoses. Even though perfect forms of species of the complex M. gyp seum were among the first to be discovered, the anamorphs are frequent ly confused with each other because of similarities of their morpholog ies on different versions of Sabouraud medium. The aim of the present study was to ascertain the distribution of mating types among clinical isolates of the M. gypseum complex recovered from animals for an epid emiological approach. Methods. The mating study was performed by cross ing 36 animal strains of the Microsporum gypseum complex isolated from 29 animals affected by dermatomycosis and 7 asymptomatic subjects wit h (+) and (-) tester strains of Nannizzia (Arthroderma) gypsea, Nanniz zia (Arthroderma) incurvata and Nannizzia (Arthroderma) fulva. All cro sses were incubated, away from the light, for 8 weeks at 25 degrees C after which they were examined for the presence or absence of asci and acospores. Results. The perfect form was found in 33 (92 %) of the is olates. N. gypsea was most frequently recovered while N. incur vara an d N. fulva were more rarely involved on animal lesions. There was a pr eponderance of the (-) strains with approximately a 2:1 ratio. Conclus ions. This is the first report on the frequence of isolation of the di fferent mating types of M. gypseum complex in Italy. The results shoul d indicate that the ability to cause skin infection of animals by the M. gypseum complex is shared by both the mating types.