| Scylla serrata ( Forskal ) belongs to Arthropoda, Crustacea, Decapoda, Protuninae, Scylla sp. . It has a wide distribution in the temperate and subtropical zone. In china it is widely distributed along the coast of Zhejiang, Fujian, Guangdong, Guangxi and Taiwan provinces, with Fujian and Guangdong having the most, and it has been one of the main economic crabs in southern China. But cultivated fry is limitied by the yield of the natural fry, and the breeding technique cannot meet the requirements of stable batch production; the fry captured from natural sea area also cannot stay level with demand.So the fundamental way to develop large area Mud Crab cultivation is breeding artificialiy. It has great practical value in aquatic animals breeding, and it can produce certain social benefits and economic benefits too.This dissertation consists of five parts. first part, the introduction, describe the purpose and the basis of this selected subjects, and analyse the present research at home and abroad in this aspect.The second part is about studies on parent crab cultivation and ripening technology. Cut through unilateral eyestalk, increase water temperature, and enhance nutrition. Use the stimulation method, alternately 1-3 h drying in the open air and pouring water, simulat the natural law of the tide continuously several days, and the effect is not good.The third part illuminates the in vitro hatch of fertilized eggs. Set different temperature gradient, 22.0℃, 26.0℃, 29.0℃, 32.0℃and normal group (24.0℃) and set parallel group, ex vivo hatch fertilized eggs, observe the hatch rates, and the results showed that 26.0-29.0℃is easier to hatch, and moreover under the condition of 29.0℃, the hatchability is the highest. In addition, observe the embryonic developmen of the ex vivo hatched fertilized eggs with microscope.The fourth part is tissue pathology observation of the death on Scylla serrata. There was a pathology study on the tissue necrosis concerning the phenomenon of a large number of death which occured in Mud Crab Scylla Serrata raised in the seawater farms in Quanzhou city of Fujian province in August 2008. By dissection, it clearly showed that the muscle necrosis had obviously melted,and the carapace had substantial accumulation of dark yellow body fluids, which was fixed into solid material by formalin. It had found the Mid-gut gland epithelial cells necrosis of ill Mud Crab and large-scale inclusions in cytoplasm by scanning with light microscope. Examination by electron microscopy showed that there were a number of doubtful bacilliform virus particles (with length of 500 nm, and width of 200 nm) within the cytoplasm of ill Mud Crab.The fifth part summarizes the full text and prospects the direction of the research. It describes the result, main innovation of this dissertation and also the existing problems, the focus of research in the future. The emphasis of the study is not only carrying out breeding and disease studies aimed directly at cultural mud crabs with high economic value to serve the cultivation and production, but also preserving species of resources, environmental protection, healthy food and public health, and exploitation and utilization of natural resources, medicine and health to solve the problems fundamentally.
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