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一、扣蟹质量的选择和鉴别1.种质(1)长江水系蟹苗生长快、个体大、性成熟晚,为最佳选择。(2)甲壳外形略呈椭圆形,背面稍平,额齿和侧齿尖锐,步足较长,第五步足趾节细长且较窄,步足刚毛短而稀,第二步足长节齿超过或接近第一前侧齿。(3)第三步足长最好超过背甲宽度的1.8倍以上。2.
First, the choice of crab quality and identification 1. Germplasm (1) Yangtze River crabs grow fast, individual large, late sexual maturity, the best choice. (2) The shape of the carapace is slightly oval, the back is slightly flat, the front teeth and the side teeth are sharp, and the foot steps are longer. The fifth step is that the toes are slender and narrow, The knuckles over or approach the first front teeth. (3) The third step is preferably more than 1.8 times the width of the carapace. 2.