Advertisements
5 January2021.
Introduction:
Andhra Pradesh recently found that ‘Mud Crab Reovirus (MCRV)’ has been the reason for mass mortality of wild crab (Scylla serrata).
Highlights
- Presence of MCRV in samples collected from Nagayalanka fields was confirmed by Joint research by Centre for Advanced Study in Marine Biology (Annamalai University, Tamil Nadu) and M.S. Swaminathan Research Foundation (MSSRF).
- MSSRF has been noticing mortality in areas like Machilipatnam and Nagayalanka in Krishna district, since 2019.
- MCRV has taken a toll on wild crab in every farming method, crab polyculture and crab fattening in which shrimp and wild crab are cultured in exclusive mud crab ponds and in same pond.
- Crab fattening technology was introduced in Andhra Pradesh by Central Institute of Brackishwater Aquaculture (CIBA-Chennai), in 2014.
About Mud Crab Reovirus (MCRV)
Mud Crab Reovirus belongs the “Reoviridae” family. It is responsible for the mass mortality of wild crabs. The virus mainly affects the connective tissue of hepatopancreas, intestine and gills.
International Case
In China, the MCRV had paralysed the wild crab species cultivation in 2007.
Case of Andhra Pradesh
- In Andhra Pradesh, total area under wild crab cultivation is around 25,000 acres. Around 4,500 acres are there in Krishna district.
- The wild crab is cultivated in the districts of Nellore, Guntur, Prakasam, Krishna, and Godavari districts.
- Wild crab is exported to South-east Asia region directly from Andhra Pradesh and it has a large market in Europe.
- But starting from 2019, around 60% of cultivation has been affected because of mass mortality in the State.
About wild crab or mud crab
- Wild Crab are scientifically called as Scylla serrata.
- They are ecologically important species of crab and are found in the estuaries and mangroves of Africa, Asia and Australasia.
- The shell colour varies from deep, mottled green to dark brown, In their most common form.