| Procambarus clarkia was an important aquculture species of China especially in the middle and lower reaches of Changjiang River because of its delicious and nutrition, its easy breeding and high price made Procambarus clarkia's breeding becme a large aquaculture industry. But the dependment of wildness seedling restrict the development of Procambarus clarkia breeding。The experiment of Procambarus clarkia's artificial propagation, breeding and diseases research included influence of veil to hatching of Procambarus clarkia germ cell and survival of juvenile, study of artificial caves, foot-incake rating, constructing the model of sex gland growth and year dynamic of plim degree, nutrition degree and mature degree, nember of spawn, toxicity of decis and research on the WSSV prevalence。Effects of 6 different shelter were investigated for 150 days, the hatching rate of the fertilized eggs under the tea branches and the palm fiber was significantly higher than that of the dried leaves, the mud and the straw for the shelter, up to 84.75% and 81.08%, respectively. Hatching rate of fertilized eggs with the straw as the shelter was the lowest and the hatching rate is 6.32%.The survival rate of juveniles under the shelter conditions was significantly different. The juvenile survival rate with the tea branches and palm fiber as the shelter was significantly higher than that of the straw, the dried leaves and the mud for the shelter. The survival rate of juvenile red swamp crayfish in the no shelter tank was the lowest In the harvest juvenile red swamp crayfish, the juvenile average individual weight in palm fiber for the shelter was significantly larger than that of the tea branches shelter and the mud shelter.The research of anniversary change on Procambarus clarkia's ovary indicate that the growth peak of ovary on Semptember contained 4 month once a year, and then degenerated graduatelly.By the means of histopathology, experimental infection and PCR, WSSV (white spot syndrome virus) was determined the cause of disease. WSSV was one kind of virus, which did not enwrapped, but diffused vastly, and with severe infections. Shrimps, trained with WSSV, perished in short order. What's more, there was no efficient medication nowadays. It also showed that there was no TSV and IHHNV infection in crayfish. The PCR, based on the specific primers, already had been applied in WSSV detection of crayfish. The outcomes of this paper firstly induced the WSSV attention to culture crayfish. What's more, a credible detection procedure had been established, all of which provided academic reference for the development of healthy crayfish culture and WSSV controlling.Following the transmission electron micrograph, PCR detection was also carried out. It was opened out that all the samples from the city of Xuyi, Lukou, Baima Lake, and Shaobo Lake were detected WSSV positively. Moreover, in different tissues of gill, heart, liver, muscle, and intestine, the virus was all detected.Also the experiment infection was performed. All the experiment infected crayfish displayed the same symptom as the sick crayfish on the culture farm. Moreover, the transmission electron micrograph and PCR detection validated the results. A comprehensive view was made that the WSSV infected the cultured crayfish, and caused the high mortality. WSSV was the cause of this severe disease.The main Crustacea disease detection procedures are composed of pathology, biology, immunology, molecule hybridizing and PCR. PCR, with the character of high specialization and less time consuming, was the first recommended choice of OIE and also exhibited good performance in the WSSV detection.It was found that, during experiment infection, the WSSV virus liquor stayed active in 4°C, while invalided in room temperature (29～31°C), which expressed that this virus invalided easily in environment. It was most likely that the virus accomplished convention and diffusion through feeding stuff.
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