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By Aasa Christine Stoltz and Camilla Bergsli
OSLO, Jan 14 (Reuters) - Marine Harvest ASA (MHG.OL), the world's biggest fish farmer, said on Monday fish disease in Chile escalated in the fourth quarter of 2007 from the third quarter, hurting its shares.
The company said that 80 million Norwegian crowns ($15.1 million) "mainly relating to expected destruction/slaughter in the first quarter will be charged in the fourth quarter accounts".
"This figure also includes a minor harvesting/destruction cost in the fourth quarter in excess of the provision made in the third quarter," Marine Harvest said.
"Since the third quarter reporting date, the negative biological situation in Chile has escalated further. ISA has continued to spread and several additional active sites in Chile are closely monitored for ISA," it said, referring to the highly contagious fish disease ISA (infectious salmon anaemia).
Marine Harvest reported its third quarter figures on Nov. 15 2007.
Shares in Marine Harvest fell 4.6 percent to 2.88 crowns by 1058 GMT, valuing the company at about 10 billion Norwegian crowns ($1.9 billion). Oslo's main index OSEBX.OL was up 0.1 percent.
ISA mainly affects Atlantic salmon. The disease is harmless to consumers but can kill fish.
The company's production in Chile will suffer in the coming quarters and will miss its forecasts for the region, the company told Reuters. In the fourth quarter, 24,300 tonnes fish were harvested in Chile.
"This is 5-6,000 tonnes below guidance. Production will be about 6-7,000 tonnes below guidance in the coming quarters," acting Chief Executive Leif Frode Onarheim said.
"This is bad news, even if volumes are as forecast. The more fish that die, the less fish they can harvest going forward," said DnB NOR analyst Klaus Hatlebrekke.
"The situation in Chile keeps getting worse. There are no indications that the situation will turn around, which is what makes people anxious," he said.
Analyst Samir Bendriss at ABG Sundal Collier said it was positive that the company would keep its guidance on volumes, where it had disappointed earlier.
Marine Harvest said it harvested 100,800 tonnes of salmon in the third quarter.
The company has initiated a new information policy where it will report shortly after the end of each quarter on actual harvest volumes.
Marine Harvest said that the long-term perspective for salmon farming in Chile was promising regardless of the current problems.
Fourth quarter results will be released on Feb. 15. (Editing by Louise Ireland)