卵生鱼类的繁殖

卵生鱼类的繁殖
卵生鱼类的繁殖方式是；雌雄亲鱼排卵排精同步进行，卵子在水中受精。鱼类极大多数为卵生繁殖后代，但因种类不同，其成熟交尾、产卵过程、卵粒特性等也有所不同。同是鱼类，不同科属、不同种类间成熟热带鱼养殖与观赏期相差很大，一般小型鱼几个月就可成熟，2～3周或几周可以繁殖1次；而大型鱼几年、十几年才成熟，1年才繁殖1次。雌鱼产浮性卵的，雄鱼先吐泡沫为巢，有的雄鱼集草为巢，受精卵在浮巢中孵化。有的鱼卵要在水流的起动漂流中孵化。雌鱼产粘性卵的，受精卵要粘附在水草或其他物体上孵化。沉性卵的受精卵沉入砂砾间隙中孵化。产卵过程和受精卵孵出仔鱼的时间，也因种有异，水温、光线、水质、溶氧量等，也都会影响到受精卵的孵化。如有不足不符，将出现孵化期延长，孵化率降低，甚至产生畸形苗。因此，对这些鱼类进行人工繁殖，要事先了解它们的繁殖特点，并细心操作。现择要为例。

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