Comparative studies on the intermediate rearing of the seeds(Scylla paramamosain﹠Scylla serreta) in outdoor pool with the net cages

Under the condition of water temperature of 25～27℃,pH of 7.5～8.5,salinity of 13～16 and continuous aeration,the experiment was conducted on two different species of juvenile crabs(Scylla paramamosain,Scylla serrata) with the cages which were made of PVC pipe and silk screen net in pools. The result showed the rates of mortality were Scylla paramamosain( 42.19%) and of Scylla serrata (32.88% ) ; the molting rates were Scylla paramamosain(42.72%) and of Scylla serrata (47.28% ). The weight coefficient were the groups Ⅰ(21.10) and the group Ⅱ(14.17); the increase of carapace length were the groups Ⅰ(337.25%) and the group Ⅱ(304.99%; the increase of carapace width are 275.00%,204.42%,had signification difference(p0.05). The relationships between the carapace length and width of three groups (Ⅰ,Ⅱ) were yⅠ= 1.6455x -1.8486,yⅡ = 1.7406x -2.7513; the relationships between the carapace width and weight of two groups were wⅠ = 0.0264e0.2818x,w Ⅱ= 0.0308e0.2772x. In conclusion ,under the condition of this experiment ,the density of juvenile crab was 417/ m2 had the highest rate of survival,the model of cultured. crabs with the cages which were made of PVC pipe and silk screen net in pools is feasible.