Investigation On The Key Transmission Routes Of WSSV In The Culture Of Fenneropenaeus Chinensis

White spot syndrome virus has not been overcome since its first outbreak in 1992, which greatly restricted the development of shrimp culture industry in China. Therefore, setting up rapid and sensitive virus detection method, understanding virus transmission route and vectors are all demanded to avoid the disease.Brooders and filial generation forepart larvaeof penaeid shrimp (Fenneropenaeus chinensis) were detected using nested-PCR for the presence of WSSV. The results showed that 4 hi 7 genealogies showed WSSV positive at 2,2 period and there's one genealogy that brooder and larvae are all showing positive. It may suggested that there exist two transmission routes of WSSV including horizontal route from the seawater to larvae and vertical route from brooders to the filial generation.Brine shrimp artemia is the key animal diet during the course of the penaied shrimp larviculture. It is very important for healthy lariculture to investigate whether it could carry white spot syndrome virus. In this study, experimentally cultured Artemia sp. with eggs and children artemia were detedcted using nested-PCR. WSSV positive products could be detected in artemia, and DNA sequence of the product accords with the designed specific amplified one according to sequence analysis. The positive rates of wild brine shrimp and filial generation were 58% and 43%, respectively. However, it seems to be no regularity between parents and filial generation's positive results. It may not judge whether WSSV could vertically transmit in artemia or not.To testify whether WSSV could spread through brine shrimp artemia to penaeid shrimp, adult Artemia sp. were infected by oral route and fed to Fenneropenaeus chinensis. The sign and pathological changes in tissues of the WSSV challenged Artemia didn't show nuclei inflation and deep color. But epithelium cells falling off and disorganization of tissue and unintegrate cell structure appeared both in the slit and transverse sections. One-wayANOVA analysis of the positive infection rates of the four experimental groups of penaeid shrimp showed that adult artemia could carry active WSSV particle and led to shrimp infection potentially.From the experiments, we might conclude that there are horizontal and vertical transmission routes during the larviculture of Fenneropenaeus chinensis, adult artemia can carry WSSV and then infect penaeid shrimp through feeding. Therefore, traditional penaeid shrimp larviculture should be reformed according to the WSSV transmission routes. Postlaval and juvenile shrimp should feed artemia rigrous quarantined, or quarantined artemia be made into microencapsulated diets as the refill of artimia and other organism diet may be in favor of the prevention of WSSV infection.