A virus which affects the ornamental fish, Koi Carp, and causes severe mortality and economic loss, has been reported for the first time in India.
Koi herpesvirus (KHV) or Cyprinid Herpesvirus-3 (CyHV-3) was first reported in Israel and Germany in 1998. Cyprinus carpio koi, commonly known as “koi or koi carp”, is an ornamental fish traded worldwide because of its striking colours, shape and scale pattern.
In India, a study was conducted from different localities at Kolathur in Chennai, the hub of the ornamental fish trade, by a research team led by A.S. Sahul Hameed, Research Coordinator of C. Abdul Hakeem College (CAHC), Melvisharam, in Ranipet district.
“Of the 108 samples, 57 of them tested positive for the virus,” said Dr. Hameed, who carried out a surveillance programme funded by the National Fisheries Development Board (NFDB) and under the Pradhan Mantri Matsya Sampada Yojana (PMMSY) to monitor disease outbreaks in aquaculture systems, including ornamental fish rearing facilities in Tamil Nadu.
Clinical signs include ulceration on body surface with loss of scales, haemorrhage on body surface and fins, necrosis of fins and discoloration of gill. Since 1998, the virus has been reported in Europe, South Africa, the U.S., Canada and Asia.
Aquarists in Kolathur had complained that the disease caused by KHV occurs regularly and causes severe mortality with heavy economic loss during winter season. This virus has been identified by PCR and genome sequencing and isolated using sensitive fish cell lines obtained from DBT funded Fish Cell line Repository established in CAHC.
“Our research finding was validated by ICAR-National Bureau of Fish Genetic Resources, Lucknow, and ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar,” he said.
Subsequently, the research work was published in the April issue of the Journal of Fish Diseases in the U.S.
Dr. Hameed said research has been initiated to develop a vaccine against KHV.