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据资料显示,每年因越冬不当而引起的鱼种死亡率,平均达到15%,华北地区的死亡率高达20%左右,有时甚至达到30%以上。这对养鱼生产来说,还因为鱼种数量的减少,而导致第二年鱼种放养量的不足,直接影响到全年的生产,损失更严重。下面就鱼种越冬死亡的原因及对策进行介绍,希望对养殖者有所帮助。
According to statistics, the annual mortality rate of fish species caused by undue winter coverage is 15% on average, while the death rate in North China is as high as 20% or even over 30%. For fish production, but also because of the reduction in the number of fish species, resulting in the second year stocking shortage, a direct impact on the production of the whole year, the loss more serious. Here are the reasons for the death of fish species and countermeasures to introduce, hoping to help farmers.