New DNA test to trace escaped farmed salmon
Thursday, January 02, 2014, 23:30 (GMT + 9)
Scientists from the Norwegian Institute of Food, Fisheries and Aquaculture Research (Nofima) have developed a new DNA test to detect the farmed salmon that escape from farms, which allows linking the DNA profile of escaped fish to the farm where they come from.
The system tests carried out on a small-scale show an accuracy of virtually 100 per cent and results obtained through industrial scale data simulation are promising.
To track escaped fish back to its owner, scientists look for genetic variants of all farmed salmon parents. To do this, they cut their adipose fins and analyze their DNA.
The offspring of common parents have a unique DNA profile, and by sending all fertilized eggs of one set of parents or parent groups to a smolt producer with a monitoring certificate, any fish coming from each smolt producer will have its unique DNA profile. This will then keep track of the fish that are transferred to a facility in the sea.
The DNA profile is stored in a national database, so that it will no longer be necessary to analyze fish in a net cage in case a leak is suspected.
After studying the DNA of escaped salmon, a match with the genetic profiles associated with a single responsible company is searched.
To determine the DNA profile, researchers select microsatellite markers of salmon genome, which are the DNA traces of salmon. Each fish has a unique DNA fingerprint, and by using a set of markers, researchers can associate an offspring to their parents.