Marine Farms subsidiary Lakeland Group on Friday announced that it stopped harvesting salmon at all of its Hoganess Salmon farm sites on the west coast of Shetland.
The decision came after about 6,000 fish were lost in one pen during a routine sea lice treatment.
An investigation commissioned by Lakeland uncovered that during the treatment sea lice products not approved for salmon may have been used, which is in conflict with Marine Farms protocol and public regulations.
Lakeland said it is investigating why the incident occurred so it can prevent it from happening again. It will not harvest or move fish from the site until an outcome has been reached.
Marine Farms will also continue to work with the Scottish Environmental and Protection Agency, animal welfare charity Scottish SPCA, the Food Standards Agency and local environmental health officials to determine the cause of the mortalities.
The incident did not have a significant financial effect of the company, according to Marine Farms.
