The veterinary services department (DVS) said polymerase chain reaction (PCR) tests carried out on the pigs from Jan 4 to 12 revealed that the pigs were infected with ASF.

“The culling was carried out through high concentration of carbon dioxide, a practice as per the animal welfare code before it was buried,” DVS said in a statement.

The state government declared the outbreak a “disaster”, with more pigs set to be culled over the next few weeks, it said.

The department will continue to take samples from pig farms within a 5km radius of the farms with positive cases. Roadblocks will be mounted in the Valdor area to prevent the movement of live pigs or carcasses to other areas, it said.

As of 2019, there were about 350,000 pigs reared in 156 pig farms in the state. Chicken remains the largest export out of the state as of 2020, with 15.1 million live birds on farms.