患小瓜虫病圆口铜鱼的组织病理学观察

多子小瓜虫（Ichthyophthirius multi filiis Fouquet，1876）主要寄生在圆口铜鱼的皮肤、鳍、颌须和鳃上．小瓜虫破坏鳃的程度分为3个层次：轻度，小瓜虫寄生在鳃上皮，鳃丝未发生粘连；中度，鳃丝发生粘连，鳃丝的基本形态仍可辨；重度，虫体大量寄生，鳃结构受到严重破坏，鳃丝基本形态以难以辨别．感染部位均有不同程度的上皮增生，形成白色囊泡；皮肤和鳃上的一些寄生部位糜烂，部分上皮缺失；鳍条被挤压变形，严重者鳍缺失．

Histopathological Observation of Coreius guichenoti Infected by Ichthyophthirius multifiliis Fouquet, 1876

Ichthyophthirius multifiliis Fouquet, 1876 usually infected the skin, gills, fins and barbels of largemouth bronze gudgeon (Coreius guichenoti (Sauvage & Dabry), 1874). The parasitization on gills was classified into three degrees:(1) slight parasitization, i. e., I. Multifiliis parasitized on epithelia and gills filaments didn't fuse together; (2) heavier parasitization, i. e. , gills filaments fused together and the filament configuration could be discerned; and (3) heaviest parasitization, i. e. , the gills filaments were seriously damaged, and their configuration could hardly be distinguished. The parasite caused hyperplasia of the host epidermis, and was surrounded by the hyperplastic tissues. When the mature parasite broke walls consisting of the hyperplastic tissues, it resulted in lesions of the parasitic sites and secondary infection of bacteria. Therefore, some infected sites were usually congestive and ulcerated. Infected barbels were ulcerated and sometimes gradually disappeared. Infected fins were also ulcerated and their rays were extruded or distorted by the trophonts of the parasite.