A.R. Thirunavukkarasu

Bio: A.R. Thirunavukkarasu is an academic researcher from Central Institute of Brackishwater Aquaculture. The author has contributed to research in topics: Sea bass & Betanodavirus. The author has an hindex of 2, co-authored 2 publications receiving 125 citations.

Development, characterization, conservation and storage of fish cell lines: a review

Abstract: Cell lines provide an important biological tool for carrying out investigations into physiology, virology, toxicology, carcinogenesis and transgenics Teleost fish cell lines have been developed from a broad range of tissues such as ovary, fin, swim bladder, heart, spleen, liver, eye muscle, vertebrae, brain, skin One hundred and twenty-four new fish cell lines from different fish species ranging from grouper to eel have been reported since the last review by Fryer and Lannan (J Tissue Culture Methods 16: 87–94, 1994) Among the cell lines listed, more than 60% were established from species from Asia, which contributes more than 80% of total fish production This includes 59 cell lines from 19 freshwater, 54 from 22 marine and 11 from 3 brackish water fishes Presently, about 283 cell lines have been established from finfish around the world In addition to the listing and a scientific update on new cell lines, the importance of authentication, applications, cross-contamination and implications of overpassaged cell lines has also been discussed in this comprehensive review The authors feel that the review will serve an updated database for beginners and established researchers in the field of fish cell line research and development

Betanodavirus and VER Disease: A 30-year Research Review.

Abstract: The outbreaks of viral encephalopathy and retinopathy (VER), caused by nervous necrosis virus (NNV), represent one of the main infectious threats for marine aquaculture worldwide. Since the first description of the disease at the end of the 1980s, a considerable amount of research has gone into understanding the mechanisms involved in fish infection, developing reliable diagnostic methods, and control measures, and several comprehensive reviews have been published to date. This review focuses on host–virus interaction and epidemiological aspects, comprising viral distribution and transmission as well as the continuously increasing host range (177 susceptible marine species and epizootic outbreaks reported in 62 of them), with special emphasis on genotypes and the effect of global warming on NNV infection, but also including the latest findings in the NNV life cycle and virulence as well as diagnostic methods and VER disease control.

Viral nervous necrosis in gilthead sea bream ( Sparus aurata ) caused by reassortant betanodavirus RGNNV/SJNNV: an emerging threat for Mediterranean aquaculture

Abstract: Viral nervous necrosis (VNN) certainly represents the biggest challenge for the sustainability and the development of aquaculture. A large number of economically relevant fish species have proven to be susceptible to the disease. Conversely, gilthead sea bream has generally been considered resistant to VNN, although it has been possible to isolate the virus from apparently healthy sea bream and sporadically from affected larvae and postlarvae. Unexpectedly, in 2014-2016 an increasing number of hatcheries in Europe have experienced mass mortalities in sea bream larvae. Two clinical outbreaks were monitored over this time span and findings are reported in this paper. Despite showing no specific clinical signs, the affected fish displayed high mortality and histological lesions typical of VNN. Fish tested positive for betanodavirus by different laboratory techniques. The isolates were all genetically characterized as being reassortant strains RGNNV/SJNNV. A genetic characterization of all sea bream betanodaviruses which had been isolated in the past had revealed that the majority of the strains infecting sea bream are actually RGNNV/SJNNV. Taken together, this information strongly suggests that RGNNV/SJNNV betanodavirus possesses a particular tropism to sea bream, which can pose a new and unexpected threat to the Mediterranean aquaculture.

Betanodavirus of Marine and Freshwater Fish: Distribution, Genomic Organization, Diagnosis and Control Measures

Abstract: The family Nodaviridae include the genera Alphanodavirus and the Betanodavirus which are non-enveloped, single stranded RNA viruses. Alphanodavirus include the insect viruses while betanodavirus include species that are responsible for causing disease outbreaks in hatchery-reared larvae and juveniles of a wide variety of marine and freshwater fish throughout the world and has impacted fish culture over the last decade. According to International Committee on Taxonomy of Viruses, the genus Betanodavirus comprises four recognized species viz barfin flounder nervous necrosis virus, red-spotted grouper nervous necrosis virus (RGNNV), striped jack nervous necrosis virus and tiger puffer nervous necrosis virus with the RGNNV being the most common. The viruses are distributed worldwide having been recorded in Southeast Asia, Mediterranean countries, United Kingdom, North America and Australia. The disease has been reported by different names such as viral nervous necrosis, fish encephalitis, viral encephalopathy and retinopathy by various investigators. The virus is composed of two segments designated RNA1 and RNA2 and sometimes possesses an additional segment designated RNA3. However, genome arrangement of the virus can vary from strain to strain. The virus is diagnosed by microscopy and other rapid and sensitive molecular methods as well as immunological assays. Several cell lines have been developed for the virus propagation and study of infection mechanism. Control of nodavirus infection is a serious issue in aquaculture industry since it is responsible for huge economic losses. In combination with other management practices, vaccination of fish would be a useful strategy to control the disease.