Investigation of the involvement of Candida albicans in hyperkeratosis of the Göttingen minipig

Abstract

At a breeding colony of Gettingen minipigs. 6404 animals born in 1995-1997 were examined for the occurence of hyperkeratosis. The percentage affected mimals varied from 1.4 to 6.9% monthly, with an average of 3.6%, 4.9% and 4.8% for the
years 1995. 1996 and 1997 respectively. Candida albicans infection was not found on the skin of the back or head of animals with hyperkeratosis. One healthy animal was positive for Candida albicans. Of the animals with brown staining at the periocular region, all findings were positive for Candida albicans. Other infections found were Candida humicola and Trichosporon spp. In connection with histological examination, Candida parapsilosis was found. The underlying cause of hyperkeratosis remains unknown. Hyperkeratosis is not associated with Candida albicans infection.
Hyperkeratosis is common in intensively housed pigs, and manifests as a brownish greasy scaling dorsal 0f the neck and back. The scales can be tubbed off. revealing normal skin underneath. Affected animals are otherwise healthy, and do not
seem to have discomfort from hyperkeratosis (Scott, 1988).
Lehman (1992) describes hyperkeratosis (hypcrkeratinization) as a diffuse proliferative, non-clevated skin alteration on the back. This in contradiction to parakeratosis, which is described as a generalized diffuse proliferative, non-elevated skin alteration. Hyperkeratosis should not be mistaken for dermatophytosis (tnycosis) or ectoparasitosis (mange).
Barrier bred Göttingen minipigs are also affected by hyperkeratosis. Young minipig boars are most frequently affected, developing signs of hyperkeratosis from the age of 6—8 weeks. Lesions may recover spontaneuosly at a later age. Previous
investigations have shown an opportunistic Candida albicans infection in connection with hyperkeratosis and exudative dermatitis of the perioeular region ofmierobiologically defined Göttingen minipigs (Madsen er al. 1998).
The present study investigates the involvement of fungal infections in hyperkeratosis it) the Göttingen minipig. The incidence of hyperkeratosis was registered, and fungal investigations were performed in order to elucidate a fungal involvement.