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河鳗又名鳗鱼、白鳝。在海水中养殖,在淡水中育肥,属于降河性洄游鱼类,是我国常见的经济鱼类之一。河鳗肉味鲜美,营养丰富,生长迅速,经济价值高,被公认为水产珍品,也是国际市场上的紧俏品。 一、生物学特性 河鳗生活在淡水水域,但产卵时须入海产卵。在每年秋季,性成熟的亲鳗大批入海繁殖,产卵后亲鳗死亡,每年春季.成群的鳗苗自海中进入江河、湖泊,在那里生长、育肥,直到性成熟入海繁殖为止。河鳗喜暗怕光,昼伏夜出;对水流敏感,爱逆水运动;善钻土,喜穴居,皮肤能营呼吸,只要身体湿润,长时间离水也不至于死亡。池塘养殖过程中,缺
River eels, also known as eel, eel. Breeding in seawater and fattening in freshwater is one of the most common economic fish in China. River eel meat taste delicious, nutritious, rapid growth, high economic value, is recognized as aquatic treasures, but also the tight market in the international market. First, the biological characteristics River eels live in freshwater waters, but when spawning eggs into the sea. In each autumn, a large number of sexually mature males march into the sea to breed, and the pro-eel dies each year after spawning. Each spring, large groups of eel fry enter the rivers and lakes from the sea and grow there and fatten until sexual maturity begins. River eel dark and afraid of light, nocturnal; sensitive to water, love against the water campaign; good drilling soil, hi cave, the skin can camp breathing, as long as the body moist, a long time from the water will not die. Pond breeding process, the lack of