草鱼出血病，4－10月为流行季节，以8—9月为最甚。危害对象为当年草、青鱼种。病鱼肌肉、口腔、各种结条基部出血，尤以臀结为甚，剥皮可见肌肉点状出血，严重病鱼肌肉全部发红，有时可见鱼体发红，有时鳃盖、下腰、肠道也有充血现象，鳃失去鲜红色，或呈苍白色。防治方法：① Grass carp hemorrhagic disease, 4-October for the popular season, 8-9 months is the worst. Harm the current year grass, herring species. Sick fish muscles, mouth, all kinds of knot at the base of the bleeding, especially in the buttocks even stripping skin visible muscle punctate bleeding, severe disease all red muscle fish, and sometimes visible red, sometimes operculum, lower back, gut There are also congestion, gills lost bright red, or pale. Prevention methods: ①