Infectivity of the Cercariae of Centrocestus Formosanus and Haplorchis Pumilio (Digenea: Heterophyidae) in Cyprinus carpio

臺灣異形吸蟲及普密略異形吸蟲對鯉魚之感染力

羅進宗(Chin-Tsang Lo) ； 李金木(Kin-Mu Lee)

《Zoological Studies》 35卷4期 (1996/10) Pp. 305-309

摘要

當把臺灣異形吸蟲（Centrocestus formosanus）之尾動幼蟲（尾幼）與鯉魚放在一起時，所有的尾動幼蟲會在30分鐘內消失，顯示可能已穿入魚體內。如用普密略異形吸蟲（Haplorchis pumilio）之尾幼，則消失時間為10分鐘。雖然幾乎所有的尾幼已消失，把魚隻在1個月後檢查時，囊狀幼蟲（囊幼）之回收率只達45.2%（臺灣異形吸蟲）及42.6 %（普密略異形吸蟲）。觀察尾幼之穿入情形時，發現有些臺灣異形吸蟲被困在魚鰓外圍之黏液中而死亡；普密略異形吸蟲之尾幼，如降落在有鱗片覆蓋之部位，則大部分不能順利穿入體內而死亡。魚體表面所分泌的黏液具有毒性，此可能是尾幼死亡之部分原因。臺灣異形吸蟲之囊幼多被細胞包圍，表示魚鰓對侵入的寄生蟲可引起強烈的細胞防禦反應。

關鍵字

異形吸蟲 ； 尾動幼蟲 ； 囊狀幼蟲 ； 感染力

並列摘要

When cercariae of Centrocestus formosanus were placed together with the carp Cyprinus carpio, all of the cercariae disappeared in 30 min, while the cercariae of Haplorchis pumilio totally disappeared in 10 min. However, only 45.2% of C. formosanus and 42.6% of H. pumilio cercariae were later recovered from C. carpio as metacercarial cysts at 1 month postinfection. The lower than expected cyst recovery rates could be explained by the trapping of many C. formosanus cercariae in the mucus secreted by the gills, and by the difficulty with which H. pumilio cercariae could penetrate the scale-covered parts of the fish. Toxic effects of mucus secreted from the body surface of the fish may be partly responsible for the demise of cercariae. The cysts of C. formosanus were encapsulated by layers of cells and fibrous material of host origin, indicating that the gills can elicit a strong tissue reaction against these parasites.

並列關鍵字

Heterophyidae ； Cercarial penetration ； Metacercaria