Isolation Rates of Fungi from Dogs and Horses in Shelters and Soil near Them

Sohng, Seung Hyun; Shin, Dong Hoon; Choi, Jong Soo

Abstract

BACKGROUND
Soil is one of the main habitat of fungi and important infection source of dermatophytosis. Objective: This study was performed to assess influence of dogs and horses to distribution of keratinophilic fungi (KPF) in soil.
METHODS
We visited 3 dog shelters and 3 horse riding grounds in Daegu and Kyeongbuk province from September to November 2012 and examined isolation rates of fungi from 88 soil samples, 16 dogs and 16 horses. By the distance away from the animal shelters, soil samples were divided into 3 groups consist of near, 10 m and 100 m. Hair and scales from skin of the dogs and the horses were collected by Mackenzie's brush technique.
RESULTS
Of the 88 soil samples examined, 35 (39.7%) yielded KPF and were all dermatophytes including Microsporum(M.) gypseum (34.1%) and Trichphyton(T.) ajelloi (5.6%). Isolation rates of KPF from the soil were observed in 79.3% of near, 40% of 10 m, and 0% of 100 m from animal shelters. Of the 16 samples from dogs, 6 (37.5%) yielded positive dermatophyte cultures and they were identified as M. canis 31.2% (5/16) and T. eboreum 6.2% (1/16). Of the 16 samples from horses, 1 (6.2%) yielded positive dermatophyte culture and it was T. eboreum.
CONCLUSION
In this study, isolation rates of KPF especially M. gypseum and T. ajelloi were higher in the soil closer to the animal shelters. Soil nearby the dogs and the horses, the environment rich in keratinous material, is conducive for the growth of dermatophytes. But M. gypseum and T. ajelloi that rich in the soil were not isolated from skin of the dogs and the horses. Their pathogenicity might be low. We consider that if not human have immune deficiency or skin injury, they do not cause infection.