The fisheries department of the Krishi Vigyan Kendra in Mainaguri block of Jalpaiguri initiated a vaccination programme of fish on Friday to improve the immunity of the Piscean population as well as to reduce the mortality rate of fingerlings.

The centre functions under the West Bengal University of Animal & Fishery Sciences.

“We have vaccinated fish at a hatchery in Mainaguri. On one hand, the vaccines will strengthen the immunity of fish. On the other hand, the mortality rate of fingerlings will reduce and will eventually help in increasing the yield in water bodies and hatcheries,” said Indranil Ghosh, a scientist at the centre.

According to him, vaccines like CIFA BROOD, which has been developed by the Centre for Freshwater Aquaculture (CIFA) for and the synthetic spawning hormones were injected in fishes at Jalpesh hatchery, a fishery in Mainaguri.

“Usually, from one lakh roe (fish eggs), around 42,000 hatchlings live, which eventually reduce to 20,000 to 28,000 fish. Now that the vaccines have been applied, this figure will go up,” Ghosh added.

On Friday, rohu and katla (major Indian carp) were vaccinated at the hatchery.

“On several occasions, we had to bear losses as less number of hatchlings used to mature. Now that the vaccines have been applied, the yield will increase and will help us,” said Kaushik Roy, who runs the hatchery.

This is the first time that vaccination of fish has been initiated in north Bengal, experts said.

“The vaccine is injected near the fins. The fish is then kept under observation and released into the water in due course. Now that the vaccines have been applied, the fish will not get infected, and the Piscean population in the entire water body will remain safe,” said an expert.

He said the vaccines injected into the fish do not have any side effects. “Eventually, we will have good quality fish and also more fish from a water body where vaccination has been carried out,” he added.

Sources said that during next year’s monsoon season, similar vaccination would be carried out in other hatcheries of north Bengal.