Malassezia pachydermatis之性狀及對貓之致病性

Characteristics of "Malassezia Pachydermatis" and Its Pathogenesis in Cats

劉邦成(Pan-Chen Liu) ； 董光中(Kwong-Chung Tung) ； 徐慶霖(Ching-Lin Shyu) ； 郭克忠(Ker-Chung Kuo)

《中華民國獸醫學會雜誌》 26卷1期 (2000/03) Pp. 72-77

https://doi.org/10.7009/JTCSVS.200003.0072

摘要

Malassezia pachydermatis分離自一隻患有外耳炎的成年貓，其生化性狀為；可分解urea、mannitol、sorbitol和peptone，在有氧和厭氧下皆可分解glucose。不能分解lactose、ornithine和citrate，不會發酵glucose產生acetoin，不產生indole，有catalase但不具有oxidase。以triple sugar iron培養基培養，不分解lactose和sucrose，不產生H2S特，不具運動性。以掃描式電子顯微鏡鏡檢，菌體大小介於長2.5μm至4.3μm，寬1.3μm至2.1μm。分生孢子為單極芽胞化，與母細胞間會形成頸圈結構，細胞壁有螺旋狀的溝紋。以10^7瘠FU/mL之菌液作耳道及皮膚接種試驗，第一組6隻貓左耳接種0.1mL菌液，右耳接種0.1mL生理食鹽水，一個月後以檢耳鏡觀察外耳道，可見6隻貓（6/6）左耳外耳道有大量濕潤的耳垢，呈黑色蠟樣式。右耳耳垢呈少量較乾燥、淡黃至淡褐色耳垢。將左耳耳垢塗抹於載玻片上，可見大量卵圓形或單極芽胞化花生狀的M. pachydermatis，革蘭氏染色呈陽性反應。右耳耳垢僅見耳道剝落的角化上皮，未發現M. pachydermatis菌體。第二組六隻貓，在靠近尾部區域皮膚接種0.1mL菌液，靠近頭部區域皮膚接種0.1mL生理食鹽水，一個月接種部位無病變產生。

關鍵字

貓 ； 耳道病害

並列摘要

Malassezia pachydermatis was isolated from otitis externa of an adult cat. This fungal strain showed neither fermentation of glucose nor assimilation of urea, mannitol, sorbitol, peptone, lactose, citrate, ornithine and sucrose. Catalase test was positive but oxidase test was negative. Indole and acetoin production were observed and no hydrogen sulfide gas were detected in triple sugar iron agar culture. The size of fungal cell measured was 2.5 to 4.3 μm ×1.3 to 2.1 μm. The cell wall had spiral grooves on its surface. Conidia could be seen on the broad base at one pole, which developed a collarette. Six cats were inoculated with 10^7 CFU/mL Malassezia pachydermatis at the left ear canal and the skin on the back near the tail, while their right ear canal and their skin on the back near the head were inoculated with 0.1 mL of saline as the controls. One month later, the left ears of all inoculated cats had increased quantity of black cerumen, while the right ears had only a small quantity of lightly yellowish-colored to brownish-colored cerumen. Gram staining of cerumen from the left ears showed many Gram positive, oval- to peanut- shaped Malassezia pachydermatis cells. Only cornified squamous epithelial cells were observed in the cerumen from the right ear. No lesions were observed on the skin of back.

並列關鍵字

Malassezia pachydermatis ； Cat ； Ear lesion