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在渔业生产上,培育鱼苗鱼种,饲养成鱼,因饲养管理不当常会发生鱼类浮头以至“泛塘”死鱼现象。成鱼和鱼种发生浮头容易判断,而鱼苗浮头往往因体小幼嫩不易判断被忽视。一些养鱼户培育鱼苗,因浮头以至泛池死了鱼,在干池对一尾鱼也没有还不知道是什么原因,因而鱼苗培育成活率很低,给养鱼户造成很大损失。笔者在长期的生产实践中,摸索出判断鱼苗浮头的方法。即在巡池时,发现鱼池水面如同雨点一般,这就是鱼苗浮头现象。说明水中氧气不足,鱼苗浮于水面吸收空气中的氧气,这时用手击掌或拍打水面,“雨点”消失,证明浮头开始,属轻
In fishery production, fish and fowl breeds are cultivated and reared into fish. Floating heads of fish and “dead fish” in Pan Tong often occur due to improper feeding practices. Into the fish and fish floating head is easy to judge, and the fry floating head is often difficult to judge because of small body is neglected. Some fish farmers cultivate fry because of the floating head and pan fish died of fish in the dry pool of a fish also do not know what is the reason, so the fry breeding survival rate is very low, causing great losses to fish farmers. The author in the long-term production practice, find out the method to determine the fry floating head. That is, when patrolling the pool, it is found that the surface of the fish pond is similar to the raindrops. This is the phenomenon of floating fish heads. Description lack of oxygen in the water, fry float on the surface of the water to absorb oxygen in the air, then clap your hands or tap the water surface, “raindrops” disappear, proof of floating head, is light