论文部分内容阅读
据上海综合试验站技术指导员在4月份对其试验站下属各试验区的摸底调查中发现,各试验区的二龄草鱼塘普遍存在着草鱼成活率低的情况,一般成活率在70%左右。在养殖过程中,没有明显的病害发生,但断断续续出现草鱼死亡。全国其他地区养殖草鱼也有同样的问题,有的地区二龄草鱼塘鱼种成活率甚至只有60%,严重影响了养殖者的经济效益。
According to the survey conducted by the Shanghai Integrated Test Station Technical Instructors in April of various pilot stations under its pilot station, the survival rate of grass carp is generally low in the second-age grass carp ponds in each experimental area, with a general survival rate of about 70% . During the breeding process, no obvious diseases occurred, but the death of grass carp occurred intermittently. Grass carp farmed in other parts of the country have the same problem. In some areas, the survival rate of second-age grass-fish pond species is only 60%, seriously affecting the economic benefits of farmers.