在渔业生产中,最令人头痛的是鱼病的危害,无论是四大家鱼还是名特水产品养殖,是养鱼老区还是城郊,鱼病的发生率都很高,受害面积大,造成的损失也比较严重。发病原因是多方面的,最重要的一条是由于一些养殖户平时不注意预防,抱着侥幸心理养鱼;其次是池塘经多年养殖后,环境恶化,致病细 In fishery production, the most troubling thing is the danger of fish diseases. Whether it is the four major fish species or the famous aquaculture, the old fish culture area or the suburbs, the incidence of fish diseases are very high and the area affected is large. Loss is also more serious. The causes are many, the most important one is because some farmers usually do not pay attention to prevention, holding the chance to fish; second is the pond after many years of breeding, the environment deteriorated, causing thin