Vaccination and other biosecurity measures are said to have nearly eliminated the need for antibacterial treatment of Norwegian farmed fish. According to the Norwegian Veterinary Institute, the negligible consumption of antibacterials in Norwegian aquaculture has contributed to driving down the risk of the development of antimicrobial resistance -- and thus transmission of such resistance to humans via fish meat. Marine salmon farming in Norway is being held up as a strong example of an animal production system in which biosecurity measures, such as vaccination, have almost totally replaced antibacterial treatment. In 2014, Norwegian salmonid production exceeded 1.3 million metric tons, with Atlantic salmon being the most important species and rainbow trout accounting for approximately 5% of production volume. In the same year, total sales of antibacterial agents for use in farmed fish were 523 kilograms' active substance, corresponding to 0.39 mg/kg produced salmonids. In comparison, this is approximately one-tenth of the antibacterial consumption per kg of meat from farm animals in Norway, which is also very low, having the lowest consumption of all European countries. Antibacterials for use in farmed fish are obtainable only by prescription, and all prescriptions are reported to the authorities. The greater part of the salmonid treatments in 2014 involved fry during the freshwater phase. Only 11 prescriptions for antibacterials involved on-growing salmon in seawater. This means that only 1% of the nearly 1,000 seawater locations reported active during 2014 were subjected to single antibacterial treatments. Source - undercurrentnews.com