Disease attack at two major salmon companies

THE disease infectious salmon anaemia (ISA) is presenting a costly headache for at least two big players in the fish farming sector, according to reports from Norway.

The country’s Food Safety Authority says it has been notified by farming giant Cermaq that it discovered evidence last week compatible with ISA at its Marøya site in the Troms region. The company states the suspicion is based on the results of histopathological examinations carried out by the Veterinary Institute, along with other results.

The Food Safety Authority plans an early inspection and tests at the facility to enable the Veterinary Institute to confirm if it is ISA. In order to limit the spread of infection, the site has been subject to the usual restrictions, including prohibiting the relocation of fish without special permission. If the suspicion is confirmed the Food Safety Authority may order the site to be completely cleared.

Meanwhile, it has done just that in the case of an ISA outbreak at the end of May at a Salaks company site in Bjørga, south of Tromso in the Solbergfjord area. Two news organisations, Nordlys and Folkebladet, say that the authority has now ordered the company to slaughter all the salmon at the site which may number up to 750,000 fish, currently weighing about a kilo each.

With salmon selling at around NOK 60 a kilo on the export market, the eventual cost to Salaks, if the fish had been allowed to reach maturity, is likely to be considerable – possibly in the order of NOK 45-million or £3.8 million.

While ISA is not harmful to humans, it is regarded as a serious and contagious viral disease in salmon.