Nutreco-owned Skretting Canada was one of two suppliers who distributed feed tainted with melamine to over 100 hatcheries and fish farms across the United States and Canada, sparking a recall and concerns over the safety of farmed fish.

China-based Xuzhou Anying Biologic Technology was identified as the source of the tainted wheat gluten, a protein source used in animal feed.

Though investigations by Canadian, American and Chinese health officials are ongoing, Skretting spokesperson Lillian Hoeivik told IntraFish her firm believes the melamine was added to the wheat gluten in an attempt to falsely raise the protein content of the gluten.

The