臺灣野生蛇類皮膚病灶真菌調查

Abstract

Chrysosporium Anamorph of Nannizziopsis vriesii（CANV）為Nannizziopsis、Ophidiomyces與Paranannizziopsis屬之真菌組成的集合體，造成多種壞死、潰瘍等皮膚病灶，近年來不斷影響圈養與野生爬蟲的健康。本研究針對台灣野生蛇類設置樣區調查，於夜間在樣區內捕捉有明顯皮膚肉眼病灶之個體，並蒐集有皮膚病灶的救傷個體，進行真菌培養與病理診斷，若發現病灶組織培養出目標真菌，且同時在組織下發現同特徵的菌絲與孢子，才定義為感染。本研究共發現1隻紅斑蛇、與1隻王錦蛇感染Ophidiomyces ophiodiicola，1隻中華眼鏡蛇病灶雖有培養出O. ophiodiicola但病理下無真菌蹤跡，以及1隻王錦蛇和1隻青蛇的表皮分離出新種的Nannizziopsis，但病理無感染證據。樣區調查之陽性率0.11%，遠低於過去國外針對野外族群之調查結果。本研究證實臺灣確實存在Ophidiomyces與Nannizziopsis屬之真菌，未來可再針對樣區內無皮膚病灶之個體以棉棒抹取樣本，檢驗是否有無症狀，但PCR陽性之個體存在，並更進一步針對棲地分布侷限（如水蛇、游蛇）及不易偵測（日行性蛇種）進行捕捉調查，以期未來更全面掌握這些真菌在臺灣野生蛇類的狀況。

Chrysosporium Anamorph of Nannizziopsis vriesii (CANV) is a collection of fungi of the genera Nannizziopsis, Ophidiomyces and Paranannizziopsis. CANV has resulted in a variety of skin lesions such as necrosis and ulcers in reptiles and continuously affected both captive and wild reptiles’ health. We investigate wild snakes with skin lesions area from night field survey and rescued individuals in Taiwan. Surgical biopsy on the lesions was performed to collected for fungal culture and histopathological diagnosis. Infection is defined as either Ophidiomyces, Nannizziopsis or Paranannizziopsis species is cultured and found under tissue pathologically at the same time. One red-banded snake and 1 king snake were infected with Ophidiomyces ophiodiicola. One Chinese cobra detected with O. ophiodiicola but without fungal elements pathologically. Novel Nannizziopsis sp. were isolated from the epidermis of one king snake and one green snake, but there was no pathological evidence of infection. Positive rate of the sample area survey was 0.11%, which was far lower than the previous field survey results from abroad. This study confirms that fungi of the genus Ophidiomyces and Nannizziopsis do exist in Taiwan. In the future, collecting skin swabs for PCR from individuals without skin lesions in the sample area would be suggested to test whether there are asymptomatic individuals that are tested positive of the target pathogens. Snakes with limited territory ( e.g. water snakes) and diurnal snake species are suggested to be further surveyed, in order to more comprehensively understand the status of these fungi in wild snakes in Taiwan.