Isolation of Trichophyton mentogrophytes var mentogrophytes from naturally infected laboratory albino rats: experimental infection and treatment in rabbits

Abstract

The present study demonstrated for the first time the occurrence of dermatophytosis in naturally infected rats and from asymptomatic and from breeding boxes of white rats kept in animal housing of college of Veterinary Medicine, University of Dohuk, Iraq. The prevalence rate of infection was (28%), clinically infected rats characterized by appearance of scaly ovoid type lesions with crusty edge and patch of hair loss mostly seen on the back, neck and face of the infected rats, itching was reported in some rats. Only one species of the trichophyton, T. mentogrophytes var mentogrophytes was isolated with growth rate (85.71%) of samples collected from clinically infected rats, and (28.57%) from asymptomatic and from breeding cages, the growth was observed within the 21 days at 25ºC on Sabouraud's Dextrose Agar. Lacto phenol cotton blue staining slides of T. mentogrophytes var mentogrophytes revealed both microconidia and macroconidia. Microconidia found in numerous numbers often in dense cluster which were hyaline, smooth walled and predominantly spherical to sub spherical in shape, varying numbers of chlamydoconidia. Spiral hyphae and smooth, thin walled clavate shaped multicelled macroconidia were also present. The study also dealt with experimental infection in rabbits with T. mentogrophytes var mentogrophytes and treated by two drugs, natural herbal preparation of acidic pomegranate (Punica granatum) fruit and synthetic nystatine ointment. The complete recovery of lesions was recorded after 14 days and 21 days of topical application of a pomegranate and nystatine ointment for 5 successive days respectively