|
C. farreri (Chlamys farreri) is one of China's northern coastal farming shellfish species. Acute viral necrosis virus \The main host of this paper has established AVNV nucleic acid detection methods, fouling organisms and the National 9 provinces and 21 sea scallop farming, breeding sea plankton, farming cage attached the farmed shellfish samples collected for testing and analysis, to explore AVNV distribution as well as the possible route of transmission. The this paper AVNV loop-mediated isothermal amplification (loop-mediated isothermal amplification, LAMP) to continuously anniversary detection of two different C. farreri breeding sea scallop research AVNV scallops in vivo infection proliferation law and to explore ecological regulation effect scallops epidemic control. The test results show that the Qingdao the flow qinghe breeding sea scallop samples, 08,09 two mass death in the summer seasons could be detected in the higher AVNV carrier rate, April -09 May 2008 the wild seeds scallops August positive the highest rate, 75 percent, annual average carrier rate of 35%; January 2009-December three kinds of the scallop seed Penglai red, artificial breeding and wild seedlings, July AVNV carrying the highest rates of respectively 20%, 70% and 80%, the scallops the carrying AVNV the positive rate and scallops mass death epidemiological characteristics of a positive correlation, while the high temperature (sea-temperature water in July and August average above 23 ℃) may be an important cause AVNV infection scallops death environmental stress factors; Sanggou Bay scallops breeding sea belongs to the shellfish algae polyculture sea, part of the seed sources detected Sanggou Bay AVNV carry the highest rate of time when the scallop seed separation hanging raising in April, Penglai red, artificial breeding and The wild seedlings AVNV carrier rate of 50%, 60% and 0, wild seedlings in May, In June, AVNV carry rate highest is 30%. 2009 flow the Qinghe scallop farms Penglai red artificial breeding of wild seedling survival rate were 39.1%, 40.7%, 45.3%; Sanggou Bay scallop farms Penglai red, artificial breeding, wild seedling survival rates were 96.8%, 89.2 %, 90%, the table Mingbei algal polyculture farming model than a single farming model can take advantage of large-scale algae the scallop farming environment ecological regulation, can significantly reduce pathogen levels, reduce scallops incidence. The 2009 Qingdao flow Qinghe the Rongcheng Sanggou Bay scallop breeding sea plankton sampling survey to study plankton capable of carrying AVNV changes. The use of real-time quantitative PCR (Real-time fluorescent quantitative PCR, FQ-PCR) technology of different particle size of plankton to carry AVNV quantitative detection, the results show that the two scallop breeding sea were detected to AVNV the positive samples, and different size plankton carry AVNV amount of different particle size less than 200 mesh plankton carry AVNV amount reached 9.45 × 106 copies / mg of DNA between the particle size of 60 mesh -200 mesh plankton, followed by a large particle size 60 mesh plankton carry the least amount of only 5.81 × 104 copies / mg of DNA. In the two scallop breeding sea are detected in August plankton carrying AVNV, coincide in time with Chlamys farreri summer phenomenon of mass death. The experimental results show that: and the the plankton can carry AVNV, may play the role of the media in the popular and spread of AVNV. 2009 two different scallop breeding sea scallops scallop cage, often several attached fouling organisms detected on its ability to carry AVNV, whether it is potential hosts of AVNV, explore attached the fouling organisms AVNV propagation play What is the role. Two sea areas Crassostrea gigas, Mytilus edulis Ascidian and straw insect samples to detect the presence of to AVNV positive Qingdao flow Qinghe scallop breeding sea Oriental sewn habitat clams is not detected AVNV positive samples exist, indicating that the long oyster Mytilus edulis, the Ascidian straw insects can carry AVNV, AVNV host is not detected AVNV Oriental sewn habitat clams may not AVNV host. 38 batches of 586 samples were collected from China's coastal provinces, 21 sea from November 2006 to November 2009, including 20 major farming shellfish which the Bivalvia shellfish 16, four kinds of gastropods. Detect these shellfish samples carrying AVNV carrying eight kinds of shellfish samples can carry AVNV, the AVNV wider host range in cultured shellfish: shrimp, scallop, Chlamys nobilis, except Chlamys farreri , short-necked clam, blue mussel, Perna viridis, Crassostrea gigas, Crassostrea rivularis and party spot Babylonia, etc.; 11 kinds of shellfish samples did not detect to AVNV positive samples, these samples, including bay scallops, the corrugated Paphia, clams, mud cockles, yellow edge roughness cockles penguin pearl oyster, Pinctada martensii, black dish Pui, Haliotis discus hannai, black abalone and Bullacta of, but is limited by the sampling location, time, and number of samples, whether these samples can carry AVNV needs further study.
|