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目前,我国北方地区的河蟹育苗生产中,大多利用亲蟹的多次抱卵习性,进行第二批及第三批的幼体孵化,以提高亲蟹及水体的利用率,达到高产的目的。但有时也会导致二次抱卵率低,抱卵量少,卵的质量差,孵出的Z1个体小,变态困难等现象。针对这一问题,我们于1998年春对前一年的越冬抱卵亲蟹通过用低温贮存、控制受精卵发育的方法,将亲蟹贮存到5月初,在第一批蟹苗出池后(5月初),再利用低温控制的亲蟹进行布苗、孵化,取得了成功,从而摆脱了以往的困境。现将这一贮存技术要点及操作规程作一介绍。
At present, most of the crabs and nursery plants in the northern part of China use the habit of holding crabs several times to hatch the second and third larvae, so as to increase the utilization rate of crabs and water and achieve high yield. But sometimes it will lead to the second holding rate is low, holding a small amount of eggs, poor quality eggs, hatched Z1 individual small, abnormalities and so on. In response to this problem, in the spring of 1998, we hoisted the crabs to the early crabs in early May through the method of low-temperature storage and control of the fertilized egg development. After the first crabs were discharged from the pond ), And then use the low-temperature control of crabs cloth seedlings, hatching, and achieved success, so as to get rid of the past predicament. Now this storage technology points and operating procedures for an introduction.