Development for control methods for factors suppressing sustainable production of aquaculture species: Experimental transmission of piscine nodavirus-induced viral nervous necrosis to the orange-spotted grouper Epinephelus coioides
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Abstract
Viral nervous necrosis (VNN) of larval orange-spotted grouper Epinephelus coioides has been recorded recently in the Philippines. The present study describes the pathogenicity of a piscine nodavirus (betanodavirus), the causative agent of VNN. Healthy orange-spotted grouper were challenged by intraperitoneal injection of the filtered tissue homogenate of VNN-diseased grouper. Abnormal swimming behavior, mortality, and necrosis and vacuolation of the brain and retina which are characteristics of VNN were reproduced in experimentally infected fish. Electron microscopic observations revealed that virus particles were present in the cytoplasm of the brain and retina; they were round in shape, without an envelope, 20 to 25 nm in diameter. The virus was reisolated from SSN-1 cells inoculated with the filtered tissue homogenate of survivors of all experimental doses. These results indicate that a piscine nodavirus from the orange-spotted grouper is the causative agent of mass mortality of this species in the Philippines.
Suggested Citation
Maeno, Y., de la Peña, L. D., & Cruz-Lacierda, E. R. (2003). Development for control methods for factors suppressing sustainable production of aquaculture species: Experimental transmission of piscine nodavirus-induced viral nervous necrosis to the orange-spotted grouper Epinephelus coioides. In Y. Ogawa, H. Y. Ogata, Y. Maeno, T. Shimoda, Y. Fujioka, & Y. Fukuda (Eds.), Proceedings of the 2nd Workshop of the JIRCAS International Collaborative Research: Studies on Sustainable Production Systems of Aquatic Animals in Brackish Mangrove Areas , December 2-3, 2002, Penang, Malaysia (pp. 89-94). Japan International Research Center for Agricultural Sciences.
Type
Conference paperISSN
1341-710XSeries
JIRCAS Working Report;No. 35Related items
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Enhancing nonspecific immune response of grouper, Epinephelus coioides using levamizole as immunostimulant
; ; Amar, Edgar
(University of the Philippines in the Visayas, 2008)
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