An enclosed Marine Harvest pen has been hit a second time by amoebic gill disease, or AGD, after being treated the disease aboard the wellboat, Ro North, just after Christmas 2017, writes newspaper Grannar.
“The treatment is in practice a lot like the de-licing farmed salmon,” said Marine Harvest’s, Ole Helge Hjetland, to the newspaper.
The amoeba paramoeba perurans unleashes AGD disease by first attacking the fish’s gills. Marine Harvest maintains the amoeba infected the fish after entering the Neptun 3 marine grow-out via an unfiltered water inlet.
There were signs of an outbreak of the disease at the facility in 2014, and 200,000 salmon were later removed.
“The (tank at Molnes, western Norway) offers us a good experience with enclosed net-pens and the technology of Aquafarm Equipment. Whether we continue to operate this way or whether we wish to invest more in this technology is under constant review,” Hjetland said.
The research pen Neptun 3 is 40 metres in diameter and 126 m in circumference. Its narrow cone is 22 m deep and offers 21,000 cubic metres of space.