The ICAR-Central Marine Fisheries Research Institute has released a virus diagnostic kit specific to betanoda virus that infects marine fish.
The kit was released during a function held at the Central Marine Fisheries Research Institute by Trilochan Mohapatra, secretary, Department of Agricultural Research and Education and director general of the Indian Council of Agricultural Research.
Betanoda virus causes Viral Nervous Necrosis (VNN), also known as viral encephalopathy and retinopathy in larvae and juveniles of marine fin fish for which no effective treatments are available and those fish surviving the infection remain carriers of the virus, facilitating vertical and horizontal transmission.
Hence, only preventive measures such as vaccination, regular screening of broodstock, eggs, larvae and fingerlings, besides effective disposal of positively diagnosed specimens, are options available to prevent disease outbreaks associated with betanodavirus in hatcheries and aquaculture farms, said a press release here.
The kit is highly specific and cost-effective. Positive reaction is diagnosed by a green fluorescence that can be perceived by the naked eye under visible or UV light and there is no need for sophisticated equipment like a thermal cycler or trans-UV illuminator as in the case of other molecular diagnostic approaches.
The kit released on Monday is meant mainly to screen marine brood stock fish to ensure certified specific pathogen-free eggs and larvae in a sensitive and rapid way. It will also help timely identification of betanoda viral infections in fish hatcheries and aquaculture systems during routine screening of eggs, larvae, fingerlings as well as trash fish used as feed during culture operations.
Hatchery production of marine fish seeds is economically important in the context of enhanced marine fish seed requirements arising out of the increasing popularity of marine cage culture along the Indian coast, the press release issued here said.