PDF(Pubmed)
Abstract：
Centrocestus formosanus is a digenean that requires three host species to complete its life cycle. This study was conducted to observe the damage caused by two life stages of the C. formosanus on its host species. The snail Melanoides tuberculata was induced to shed cercariae by exposing to sunlight and specimens of koi carps were experimentally infected with cercariae. Gills of two infected fish were killed and fixed in Bouin\'s solution daily for 21 days. Infected fish were continuously fed to a pond heron (Ardeola ralloides) for three weeks and therafter the bird was killed. Small intestine was resected as duodenum, jejunum, and ileum and fixed in formol saline. Gills and small intestine were prepared to study the histopathological damages. Flared opercula with protruding gills and increased respiratory rate were identified as the primary clinical signs of the fish. Encysted metacercariae were observed in the basal, middle and in the apical portion of the gills\' filaments and gradual distortions and extensive proliferation of the cartilage of the gills resulted in loss of the respiratory epithelium. A progression of fibroblast to chondroblast encapsulation of the parasite was observed in the gill of fish as a host response. The duodenum of the heron was severely infected with adult parasites than jejunum and ileum. Flukes were observed in the villi, mucosae, submucosae, and also in the tunica muscularis of the duodenum. In conclusion, this study revealed that the heavy infection of C. formosanus could cause severe pathological lesions in both koi carps and pond heron.
摘要：
Centrocestusformosanus是一种双生动物，需要三个宿主物种来完成其生命周期。进行这项研究是为了观察Formosanus的两个生命阶段对其宿主物种造成的损害。通过暴露于阳光下，诱使蜗牛Melanoidestaterculata脱落，并通过实验感染了尾c。杀死两条被感染的鱼，并每天在Bouin's溶液中固定21天。将被感染的鱼连续喂食池塘苍鹭（Ardeolaralloides）三周，然后将其杀死。小肠被切除为十二指肠，空肠,和回肠并固定在生理盐水中。准备ill和小肠以研究组织病理学损害。带有突出g和呼吸频率增加的扩孔被确定为鱼类的主要临床体征。在基底观察到囊虫，中段和顶端部的的\'丝和逐渐扭曲和广泛的增殖的软骨的the的呼吸上皮的损失。作为宿主反应，在鱼的g中观察到成纤维细胞向成软骨细胞包裹寄生虫的进展。苍鹭的十二指肠比空肠和回肠严重感染成年寄生虫。在绒毛中观察到了吸虫，粘膜，粘膜下，以及十二指肠的肌层。总之,这项研究表明，福尔马沙的严重感染可能会导致锦鲤鱼和池塘鹭的严重病理损害。
