一种危害眼斑拟石首鱼的寄生涡虫及其防治

Turbellarian parasitised in Sciaenops ocellatus and its control

眼斑拟石首鱼(Sciaenops ocellatus)俗称美国红鱼,又称红鼓鱼,是福建水产养殖业中重要养殖鱼类之一.它们生长速度快,对饲料的适应性强,饵料转化率高,一年即可养成1kg重的成品鱼,出口韩国,价格好.较之养殖大黄鱼具有成本低,经济效益好,资金周转快,成活率高等优点.福建省罗源湾的水质适于养殖美国红鱼,因此,近年大量投苗养殖,但在养殖中出现了各种各样的病害.我们在诊治美国红鱼幼鱼(100g左右)大量死亡的病例中,发现鱼鳃上寄生了一种罕见的涡虫,它们没有钩和吸盘,寄生方式特殊,由鱼鳃分泌的大量粘液和增生的组织将其包裹.涡虫的寄生造成幼鱼鳃丝间塞满了泥土样脏物及鳃丝严重缺损,鱼因呼吸困难而死亡.

During the treatment of mass death of American red drum ( Sciaenops ocellatus)(100g), a rare kind of turbellarian was found on gill. The turbellarian, without hood and sucker, attached gill with a lot of mucus secreted by fish and was surrounded by hyperplasia histon. The gill was filled with mud and damaged seriously by the parasites. Fishes died of breath difficulty. The disease was successfully controlled by treatment of formalin and crystal dipterex, but there was 15% death rate after the treatment. So, the parasites may be the main reason for the fish death. This kind of turbellarian not only parasitize in red drum, but also in croaker, sometimes in young and adult in our further study. There are not any reports about the parasites all around China.