The Norwegian Veterinary Institute has named the top causes of salmon deaths for the first four months of the year.
Infectious diseases were the primary cause of death in salmon at sites monitored by the Norwegian Veterinary Institute during the first four months of 2024, the body announced on Wednesday.
“Infection diseases accounted for nearly half (46%) of the mortality nationwide in the first tertial, while injuries accounted for 22% and environmental conditions for 10%. Winter ulcers were the most significant infectious disease recorded during this period, whereas cardiomyopathy syndrome (CMS) and heart and skeletal muscle inflammation (HSMB) had relatively minor importance. Handling is cited as a significant cause of injuries,” the institute stated.
Veterinarian Torfinn Moldal, the head of fish health at the Veterinary Institute, noted that in January, jellyfish were a significant cause of mortality in the northernmost regions.
“Environmental conditions were registered as a significant contributor to mortality in January, particularly in the northernmost production areas (PO10-13). Jellyfish accounted for nearly all mortality linked to ‘environmental conditions’ in PO10-13 in January,” the Veterinary Institute reported.
“Given the challenges many sites experienced with jellyfish before Christmas, it is not surprising that jellyfish also caused mortality in the new year. Winter ulcers and handling injuries are also known causes of mortality. However, it is somewhat surprising that CMS and HSMB are considered to have such little importance as causes of mortality in this period,” said Moldal in the announcement.
