A Clinical and Histopathological Study of Experimental Canine Scabies

ABSTRACT

BACKGROUND: Canine scabies is caused by an infestation of Sarcoptes scabiei var. canis (S. canis) in dogs and they can be transmitted to humans. Recently pet raising has been increasing in Korea and various parasitic infestations contracted from them have also been increasing including canine scabies. OBJECTIVE: The purpose of this study was to examine the clinical and histopathological features of experimental canine scabies. METHODS: Two dogs experimentally infested were observed for a year. They were examined physically and the numbers of S. cans were counted from scraping samples of the ear, leg and abdomen every 3 to 7 days and skin biopsies were taken. One was given systemic corticosteroids(Dogl) and the other was observed in its natural course(Dog2). RESULTS: Dogl-Clinically severely pruritic, markedly thick hyperkeratotic scales, crust and generalized erythema on the whole body developed with huge numbers(up to 754.9/100mg from scales of the abdomen) of mites, and histopathologically showed features similar to human crusted scabies. Dog2-Clinically showed milder features than Dogl including the number of S. canis(up to 242.6/100mg from scales of the ear), but histopathologically showed similar features with Dogl. Dog2 also showed a prompt response to one topical application of 20% benzyl benzoate solution. CONCLUSIONS: 1) The number of S. canis increased markedly in both normal and corticosteroidtreated dogs, although it was more significantly increased in the corticosteroid-treated one. 2) Histopathology showed features similar to classical scabies in the early stage but features of human crusted scabies in the full-blown stage. 3) Morphologically Sarcoptes canis differs from Sarcoptes scabiei var. hominis.