The occurrence of tilapia parvovirus (TiPV) affecting farm-bred tilapia, a freshwater fish species, and causing a huge mortality rate has been reported for the first time in India at ponds in Walajah in Ranipet district.
“Fish samples were collected from 10 ponds in the farm and fish from eight ponds showed TiPV-positive by PCR. This DNA virus caused mortality ranging from 30 to 50% in the farm and 100% mortality in the laboratory,” said Dr. Sahul Hameed, Director, Aquatic Animal Health Laboratory (AAHL) of C. Abdul Hakeem College (CAHC) at Melvisharam.
Considered as “a poor-man’s fish”, Mozambique tilapia was introduced to Indian fresh water bodies in the 1950s and it is called Jilabi in Tamil. Capable of surviving in low-oxygen levels in water, the fish has turned invasive across the country. Nile tilapia introduced in the 1970s is a little bigger and is cultured on a large-scale and available in the market for ₹100 to ₹150 per kg.
Dr. Sahul Hameed said among the tilapia species, the Indian government had authorized import of only Oreochromis niloticus in 1970 and red hybrids because of their fast growth and market demand.
In India, tilapia farming is being carried out in different parts of Andhra Pradesh and Kerala, and is sold in domestic markets as whole fish. In 2022, the tilapia production was estimated at about 70,000 tonnes, of which 30,000 tonnes come from aquaculture.
The AAHL of C.Abdul Hakeem College has been carrying out screening of tilapia regularly for viral pathogens under the R&D programme, funded by the Department of Biotechnology, Government of India, for developing vaccines against them.
“While screening the fish for viral pathogens in the months of February and March 2023, the research team reported the occurrence of Tilapia parvovirus,” explained Dr. Sahul Hameed, who led the research team.
The TiPV was first reported in China in 2019 and Thailand in 2021. India is the third country to report the occurrence of TiPV.
“Our research finding has been validated by ICAR-National Bureau of Fish Genetic Resources, Lucknow, ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar and Kerala University of Fisheries and Ocean Studies, Cochin,” said Dr. Sahul Hameed.
The finding has been communicated to Archives of Virology (Springer Nature Switzerland AG) for publication.
Dr Sahul Hameed said that research should be initiated to develop a vaccine against TiPV to help fish farmers to prevent the loss due to TiPV and action must be taken immediately to prevent its spread to other regions of India.
