指环虫是一种在鲤鱼鳃瓣上全都能看到的单殖类,尤其是静水和蓄水池的鲤鱼养殖场容易流行指环虫病。它对大型鱼几乎没有什么实际损害,但对稚幼鱼则是造成阻碍生长和死亡的病因。其症状是,病鱼无力游动,也不聚集在投饵场所。由于鳃上皮增生 Finger worm is a mononuclear species that can be found on all the carp gills, especially in the carp farms of still water and reservoirs. It has little practical impact on large fish, but juveniles are the cause of obstruction to growth and mortality. The symptom is that diseased fish are unable to swim and do not gather at the place of feeding. Because of gill epithelial hyperplasia