一、病原体异沟虫属八铗科,虫体扁平细长,舌状,长5—20毫米,虫体后部延长,后固着器上有4对固着铗,最末端一对稍小。二、流行情况该病从发生到死亡一般历程较长,发病率90%以上,死亡率75%。特别是夏季最为严重,异沟虫是嗜血性的单殖吸虫。鱼体被虫寄生后,严重贫血,不食少动,但生 First, the pathogens heteroptera is eighty family, long flat slender body, tongue, 5-20 mm long, insect body extension of the rear, after the fixer has 4 pairs of fixed 铗, the end of a pair of slightly smaller. Second, the prevalence of the disease from the onset of the general history of death longer, the incidence of 90% or more, the mortality rate of 75%. Especially in the summer is the most serious, heterophylla is a monotonous blood monster. Fish parasitic parasites, severe anemia, eat less, but students