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人们饲养家禽家畜,其产卵(仔)数量往往是屈指可数,而生活在海洋、湖泊中鱼类的产卵量。却是形形色色,数量相差悬殊,如鳐、鲼,锯尾鲨、鼠鲨等产卵量为2～7粒,黄鳝、杜父鱼、罗非鱼产卵量为500～1000粒,细鳞鱼、大麻啥鱼产卵量为2000～5000粒,鲫鱼、鲤鱼、乌鱼、狗鱼产卵量为1万～10万粒。草、鳙、鳕鱼、大黄鱼的产卵量为10万～100万粒,鳗鲡的产卵量则在1000万粒以上,翻车鲀的产卵量更高,为3亿粒左右。由此看来,不同鱼类的产卵量相差可达近亿倍。
People raising poultry and livestock, the number of spawning (Aberdeen) is often a handful, while living in the oceans, lakes, fish fecundity. But it is all kinds of, the amount of disparities, such as 鳐, 鲼, sawtooth shark, rat shark and other spawning amounts of 2 to 7, eel, Dufusa, tilapia fecundity of 500 to 1000, , Marijuana fish spawning amount of 2000 to 5000, crucian carp, carp, mullet, dog fish oviposition of 10,000 to 100,000. Grass, 鳙, cod, big yellow croaker spawning volume of 100000 ~ 1000000, the eel 产 eggs in more than 10 million, turning 车 spawning more, for 300 million or so. Seen in this light, the difference in fecundity of different fish up to nearly 100 million times.