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由于温度的变化,鱼苗下池稍不注意,就会引起感冒,轻则影响生长,重则造成批量死亡,1989年4月,桃江、安化等县从广东省购进家孵鱼苗1500万尾,因两地温差较大,加上下池遇上寒流,鱼苗死亡约1100万尾,成活率仅26％。鱼苗下池患感冒是生产中常见而又易忽视的一种鱼病。鱼类是变温动物,其体温随水温的高低而升降,但鱼体温和周围水体的温差大约为0.1℃。因此,当把鱼苗从一个环境转入到另一个环境时,两处的水温若相差2℃,鱼苗就很难适应,鱼苗的适应能力极弱,故极易患感冒。鱼苗感冒的主要症状是行动失常、漂浮水面,严重时出现
Due to the change of temperature, fry under the pool a little attention, it will cause a cold, ranging from the impact of growth, while causing mass mortality, in April 1989, Taojiang, Anhua and other counties purchased from Guangdong Province, Due to the large temperature difference between the two places, coupled with the pool encounter cold, fry death of about 11 million, the survival rate of only 26%. Fries under the pool suffering from cold is a common and overlooked production of a fish disease. Fish is a variable temperature animal, its temperature rises and falls with the level of water temperature, but the temperature difference between the water body and the surrounding water is about 0.1 ℃. Therefore, when the fry is transferred from one environment to another, if the difference between the temperatures of the two places is 2 ° C, the fry will be hard to adapt and the adaptability of the fry will be extremely weak. Therefore, it is susceptible to a cold. The main symptoms of cold fry are maladaptation, floating surface, appears when serious