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(四) 原生动物引起的鱼病的防治 1.隐鞭虫病 危害性:病原体主要有颤动隐鞭虫和鳃隐鞭虫两种。颤动隐鞭虫主要寄生在鱼皮肤上,其次是鳃瓣。草鱼、青鱼、鲢、鳙、鲤、鲫、鳊、鲮以及其他许多淡水鱼类都有不同程度的感染,特别是鲮和鲤的鱼苗,最易被侵袭。大量寄生时,可引起鱼苗身体瘦弱,甚至死亡。鱼种阶段中主要寄生在鳃瓣,危害就比较小。成鱼阶段虽然也可
(D) of the protozoa caused by the prevention and treatment of fish diseases 1. Whip whip disease hazard: pathogens are mainly whip whip whip whip whip torture and gill two. Whip whip whip whip main parasitic fish skin, followed by the gill flap. Grass carp, black carp, silver carp, bighead carp, carp, crucian carp, pomfret, 鲮, and many other freshwater fish all have different levels of infection, especially fry and carp fry, most vulnerable to attack. When a large number of parasites, can cause fry body thin, or even death. Fish species mainly parasitic in the gill flap stage, the harm is relatively small. Although the fish stage can be