文蛤牛首科吸虫寄生病的组织病理学

Histopathology of bucephalidae larvaecaused disease in Meretrix meretrix

报道了一种牛首科(Bucephalidae)吸虫幼虫在文蛤体内的寄生情况以及所引起的组织病理学变化。观察结果表明,该吸虫幼虫主要侵占生殖腺,少部分进入附近的消化盲囊、鳃、外套膜和足等。消化道中未发现其存在。寄生虫不仅破坏已感染的组织,未感染部位的组织结构也呈现一定的病理学变化。严重感染时,生殖腺完全被吸虫幼虫侵占;消化盲囊、消化道和鳃等器官组织的上皮细胞脱落或溃散;肌肉紊乱或溶解等。严重者导致器官组织坏死,贝类死亡。

This paper reports the histopathology of Meretrix meretrix Linnaeus parasitized by the larvae of Bucephalidae. The specimens were collected from molluscafarming ponds in Laizhou, Shandong province in March, 2001. The main symptoms of infected clams is that the visceral mass becomes thin, the adductor muscle is weak and the surface of the shell lacks luster. Histological examination revealed that most of the larvae occupied the genital gland of the clam, with relatively few in other organs. It damages not only the tissues parasitized by the parasites, but also caused the debilitation of other organs. In heavy infestations, the gonads is completely destroyed and replaced by mass of larval digeneans. Other organs exhibited obvious pathological changes, e. g. the epithelial cells detached from the wall of digestive tract, digestive diverticula and gills. The structure of muscular tissues becomes irregularly arranged, with some tissue melted. In the end, all of the essential organs were broken down, which causes the host dead.