RESEARCH ARTICLE Development of Snake Fungal Disease after Experimental Challenge with Ophidiomyces ophiodiicola in Cottonmouths (Agkistrodon

Snake fungal disease (SFD) is a clinical syndrome associated with dermatitis, myositis, osteomyelitis, and pneumonia in several species of free-ranging snakes in the US. The causative agent has been suggested asOphidiomyces ophiodiicola, but other agents may contribute to the syndrome and the pathogenesis is not understood. To understand the role ofO. ophiodiicola in SFD, a cottonmouth snake model of SFD was designed. Five cotton-mouths (Agkistrodon piscivorous) were experimentally challenged by nasolabial pit inocula-tion with a pure culture ofO. ophiodiicola. Development of skin lesions or facial swelling at the site of inoculation was observed in all snakes. Twice weekly swabs of the inoculation site revealed variable presence ofO. ophiodiicola DNA by qPCR in all five inoculated snakes for 3 to 58 days post-inoculation; nasolabial flushes were not a useful sampling method for detection. Inoculated snakes had a 40%mortality rate. All inoculated snakes had microscopic lesions unilaterally on the side of the swabbed nasolabial pit, including ero-sions to ulcerations and heterophilic dermatitis. All signs were consistent with SFD; how-ever, the severity of lesions varied in individual snakes, and fungal hyphae were onl