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1988和1989两年,我们在面积为5000亩的鄂州市三山村湖泊进行投饵放养幼蟹,取得了明显的效果。两年回捕率分别为31.42%和30.93%;个体均重分别为125克和160克;150克以上的个体1988年占45%,1989年占84%。产品全由外贸部门收购,经济效益1988年平均售价22元/公斤,获纯利润33.4万元,1989年平均售价34元/公斤,在蟹种和饲料价格上涨因素影响下,仍获纯利8.4万元。两年实践表明:湖泊投放幼蟹生长迅速,商品率高,效益大,且能当年投产当年受益,是开发利用中小型湖泊的有效途径。饲养方法如下:一、湖泊条件面积为5000亩的封闭型湖泊,水深1.4—1.8米,水质清新无污染,透明度45厘米左右。水生植物较少,覆盖率不足40%,以聚草和野菱
In 1988 and 1989, we stocked juvenile crabs in the Sanshan Village of Ezhou, an area of 5,000 mu, and achieved remarkable results. The two-year recovery rate was 31.42% and 30.93% respectively; both were 125 and 160g respectively; those with more than 150g accounted for 45% in 1988 and 84% in 1989. The products were all acquired by the foreign trade department. The average selling price of the products in 1988 was 22 yuan / kg, and the net profit was 334,000 yuan. The average selling price was 34 yuan / kg in 1989, and was still net profit under the influence of price increase of crab species and feed 84,000 yuan. Two years of practice show that larvae laying crabs grow rapidly, the commodity rate is high, the benefits are large, and they can benefit from the year when they were put into production. It is an effective way to develop and utilize small and medium sized lakes. Feeding methods are as follows: First, the lake conditions of 5000 acres of closed lake, water depth of 1.4-1.8 meters, fresh water pollution, transparency of about 45 cm. Less aquatic plants, coverage less than 40%, with poly grass and wild Ling