Korean Journal of Ichthyology (한국어류학회지)

The Ichthyological Society of Korea (한국어류학회)
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A Case Study of Mortality Caused by Viral Encephalopathy and Retinopathy (VER) in Cultured Sevenband Grouper, Epinephelus septemfasciatus during Winter

겨울철 양식 능성어의 바이러스성뇌망막증(VER) 감염사례

  • Won, Kyoung Mi (Pathology Research Division, National Institute of Fisheries Science) ;
  • Lee, Jeong Tae (GyeongSangNamDo Fisheries Resources Research Institute) ;
  • Cho, Mi Young (Pathology Research Division, National Institute of Fisheries Science) ;
  • Kim, Myoung Sug (Pathology Research Division, National Institute of Fisheries Science) ;
  • Kim, Na Young (Pathology Research Division, National Institute of Fisheries Science) ;
  • Jung, Sung Hee (Pathology Research Division, National Institute of Fisheries Science) ;
  • Lee, Nam Sil (Pathology Research Division, National Institute of Fisheries Science)
  • 원경미 (국립수산과학원 병리연구과) ;
  • 이정태 (경상남도 수산자원연구소) ;
  • 조미영 (국립수산과학원 병리연구과) ;
  • 김명석 (국립수산과학원 병리연구과) ;
  • 김나영 (국립수산과학원 병리연구과) ;
  • 정승희 (국립수산과학원 병리연구과) ;
  • 이남실 (국립수산과학원 병리연구과)
  • Received : 2017.09.12
  • Accepted : 2017.09.26
  • Published : 2017.09.30
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Abstract

In 2015, a nervous necrosis virus (NNV) was isolated from sevenband grouper, Epinephelus septemfasciatus, maintained in land-based aquaculture system at below $12^{\circ}C$ in winter. Mortality was up to 30% in brood fish, over 4 kg of body weight. Moribund fish showed clinical sings typical of viral encephalopathy and retinopathy (VER), also called viral nervous necrosis (VNN), such as uncoordinated, corkscrew-like swimming behavior, belly-up at rest, darkening of body, cloudy eyeball and hyperinflation of the swim bladder. Aetiology of the disease was confirmed by gross observation of clinical signs, histopathology and molecular diagnosis. Histological studies revealed severe vacuolation and necrosis in the brain. Molecular diagnosis by revere transcription-polymerase chain reaction (RT-PCR) specific to batanodavirus yielded a positive result. The nucleotide sequences of the PCR-amplified fragment were 99.48~100% similar to barfin flounder nervous necrosis virus (BFNNV) genotype and most closely aligned with Pacific cod betanodavirus (PCNNV). This is the first report of natural batanodavirus, NNV infection in sevenband grouper reared in low water temperature during winter (below $12^{\circ}C$) in Korea.

2015년 겨울, 우리나라 남해안 소재 육상 양식장에서 사육 중이던 능성어의 약 30%가 폐사하였다. 수온 $9{\sim}12^{\circ}C$의 겨울철에 발생한 능성어 폐사는 신경괴사성바이러스 (NNV) 감염에 의한 바이러스성뇌망망증 (VER)으로 밝혀졌다. 시험어는 비정상적인 유영, 배를 위로한 채 수면을 떠 다니는 현상, 체색흑화, 안구백탁 및 부레의 과도한 팽창 소견을 보였다. 원인 바이러스는 일반적으로 고수온기 능성어에 감염되는 RGNNV genotype이 아닌, 냉수성 어류에서 분리되는 BFNNV genotype으로 밝혀졌으며, NNV 가장 근연관계가 높은 Pacific cod betanodavirus (PCNNV)와 99.7~100% 상동성을 보였다. 병리조직학적 관찰 결과, 바이러스성뇌망망증 (VER)의 특징적인 병변인 뇌조직의 공포화 및 괴사를 수반하였다. 이 연구는 수온 $12^{\circ}C$ 이하의 겨울철에 능성어에 감염된 BFNNV genotype에 대한 첫 보고이다.

Keywords

References

  1. Aspehaug, V., M. Devold and A. Nylund. 1999. The phylogenetic relationship of nervous necrosis virus from halibut (Hippoglossus hippoglossus). B. Eur. Assoc. Fish. Pat., 19: 196-202.
  2. Ball, L.A., D.A. Hendry, J.E. Johnson, R.R. Ruechert and P.D. Scotti. 2000. Family Nodaviridae. In: Van Regenmortel M.H.V., Fauquet C.M., Bishop D.H.Z., Carstens E.B. and 7 others (eds.), Virus taxonomy. Seventh report of the International committee on Taxonomy of Viruses. Academic Press, New York, pp. 747-755.
  3. Barker, D.E., A.M. Mackinnon, L. Boston, M.D.B. Burt, D.K. Cone, D.J. Speare, S. Griffiths, M. Cook, R. Ritchie and G. Olivier. 2002. First report of piscine nodavirus infecting wild winter flounder Pleuronectes americanus in Passamaquoddy Bay, New Brunswick, Canada. Dis. Aquat. Organ., 49: 99-105. https://doi.org/10.3354/dao049099
  4. Breton, L.A., L. Grisez, J. Sweetman and F. Ollevier. 1997. Viral nervous necrosis (VNN) associated with mass mortalities in caged-reared sea bass Dicentrarchus labrax L. J. Fish Dis., 20: 145-151. https://doi.org/10.1046/j.1365-2761.1997.00284.x
  5. Cha, S.J., J.W. Do, N.S. Lee, E.J. An, Y.C. Kim, J.W. Kim and J.W. Park. 2007. Phylogenetic analysis of betanodaviruses isolated from cultured fish in Korea. Dis. Aquat. Organ., 77: 181-189. https://doi.org/10.3354/dao01840
  6. Cho, M.Y., G.H. Park, B.Y. Ji and J.W. Kim. 2010. Statistical data on fish virus of cultured olive flounder, Paralichthys olivaceus from 2005 to 2007. J. Fish Pathol., 23: 155-163. (in Korean)
  7. Fukuda, Y., H.D. Nguyen, M. Furuhashi and T. Nakai. 1996. Mass mortality of cultured sevenband grouper, Epinephelus septemfasciatus, associated with viral nervous necrosis. Fish Pathol., 31: 165-170. https://doi.org/10.3147/jsfp.31.165
  8. Gomez, D.K., G.W. Baeck, J.H. Kim, C.H. Choresca Jr. and S.C. Park. 2008. Molecular detection of betanodavirus in wild marine fish populations in Korea. J. Vet. Diagn. Invest., 20: 38-44. https://doi.org/10.1177/104063870802000107
  9. Hegde, A., H.C. The, T.J. Lam and Y.M. Sin. 2003. Nodavirus infection in freshwater ornamental fish, guppy Poicelia reticulate-comparative characterization and pathogenicity studies. Arch. Virol., 148: 575-586. https://doi.org/10.1007/s00705-002-0936-x
  10. Jithendran, K.P., M.S. Shekhar, S. Kannappan and I.S. Azad. 2011. Nodavirus infection in freshwater ornamental fishes in India: diagnostic histopathology and nested RT-PCR. Asian Fish. Soc., 24: 12-19.
  11. Johansen, R., S. Grove, A.K. Svendsen, I. Modahl and B. Dannevig. 2004. Asequential study of pathological findings in Atlantic halibut, Hippoglossus hippoglossus (L.), throughout one year after an acute outbreak of viral encephalopathy and retinopathy. J. Fish Dis., 27: 327-341. https://doi.org/10.1111/j.1365-2761.2004.00548.x
  12. Kurita, J., K. Nakajima, I. Hirono and T. Aoki. 1998. Polymerase chain reaction (PCR) amplification of DNA of red sea bream iridovirus (RSIV). Fish Pathol., 33: 17-23. https://doi.org/10.3147/jsfp.33.17
  13. Munday, B.L., J. Kwang and N. Moody. 2002. Betanodavirus infections of teleost fish: a review. J. Fish Dis., 25: 127-142. https://doi.org/10.1046/j.1365-2761.2002.00350.x
  14. Mushiake, K., T. Nishizawa, T Nakai, I. Furusawa and K. Muroga. 1994. Control of VNN in striped jack: Selection of spawners based on the detection of SJNNV gene by polymerase chain reaction (PCR). Fish Pathol., 29: 177-182. https://doi.org/10.3147/jsfp.29.177
  15. Nakai, T., K. Mori, T. Sugawa, T. Nihioka, K. Mushiake and H. Yamashita. 2009. Current knowledge on viral nervous necrosis (VNN) and its causative betanodaviruses. Isr. J. Aquacult- Bamid., 61: 198-207.
  16. Nishizawa, T., M. Furuhashi, T. Nakai and K. Muroga. 1997. Genomic classification of fish nodaviruses by molecular phylogenetic analysis of the coat protein genes. Appl. Environ. Microb., 63: 1633-1636.
  17. Nishizawa, T., K. Mori, T. Nakai, I. Furusawa and K. Muroga. 1994. Polymerase chain reaction (PCR) amplification of RNA of striped jack nervous necrosis virus (SJNNV). Dis. Aquat. Organ., 18: 103-107. https://doi.org/10.3354/dao018103
  18. Oh, M.J., I. Takami, T. Nishizawa, W.S. Kim, C.S. Kim, S.R. Kim and M.A. Park. 2012. Field tests of poly (I:C) immunization with nervous necrosis virus (NNV) in sevenband grouper, Epinephelus septemfasciatus, (Thunberg). J. Fish Dis., 35: 187-191. https://doi.org/10.1111/j.1365-2761.2011.01334.x
  19. OIE. 2017. World Organization for Animal Health, Manual of Diagnostic Tests for Aquatic animal. http://www.oie.int/international-standard-setting/aquatic-manual/access-online (2017.09.05. 09:10).
  20. Oseko, N., T.T. Chuah, V. Palamisamy, Y. Maeno and J. Kurita. 2004. Iridovirus isolated from diseased sea bass Lates calcarifer and red drum Sciaenops ocellatus causing mass mortality in Malaysia. In: 7th Asian Fisheries Forum 04 Abstracts, Penang, Malaysia, 127.
  21. Patel, S., K. Korsnes, O. Bergh, F. Vik-Mo, J. Pedersen and A.H. Nerland. 2007. Nodavirus in farmed Atlantic cod Gadus morhua in Norway. Dis. Aquat. Org., 77: 169-173. https://doi.org/10.3354/dao01842
  22. Patrick, T.K.W. and R.C. Cipriano. 2017. Fish viruses and bacteria-Pathobiology and protection. pp. 128-146. CAB international.
  23. Shetty, M., B. Maiti, K.S. Santhosh, M.N. Venugopal and I. Karunasagar. 2012. Betanodavirus of marine and freshwater fish: Distribution, genomic organization, diagnosis and control measures. Indian J. Virol., 23: 114-123. https://doi.org/10.1007/s13337-012-0088-x
  24. Shimo, S., Y. Akimoto and H. Takahama. 2000. Bibliographical study of the thermal effects on marine organisms. Rep. Mar. Ecol. Res. Inst., 2: 1-315.
  25. Snow, M., N. Bain, J. Black, V. Taupin, C.O. Cunningham, J.A. King, H.F. Skall and R.S. Raynard. 2004. Genetic population structure of marine viral haemorrhagic septicemia virus (VHSV). Dis. Aquat. Org., 61: 11-21. https://doi.org/10.3354/dao061011
  26. Sohn, S.G., M.A. Park, M.J. Oh and S.K. Chun. 1998. A fish nodavirus isolated from cultured sevenband grouper, Epinephelus septemfasciatus. J. Fish Pathol., 11: 97-104. (in Korean)
  27. Sohn, S.G. and S.K. Chun. 1999. Pathogenicity of the fish nodavirus causing viral nervous necrosis of sevenband gropuer, Epinephelus septemfasciatus. J. Fish Pathol., 12: 107-113. (in Korean)
  28. Tanaka, S., H. Aoki and T. Nakai. 1998. Pathogenicity of the nodavirus detected from diseased sevenband grouper Epinephelus septemfasciatus. Fish Pathol., 33: 31-36. https://doi.org/10.3147/jsfp.33.31
  29. Yuwanita, R., Y. Yanuha and Hardoko. 2013. Pathognomonic of viral nervous necrosis (VNN) virulence on larvae of humpback grouper (Cromileptes altivelis). Adv. Environ. Biol., 7: 1074-1081.