The infectious salmon anemia (ISA) outbreak that has crippled Chile's salmon-farming industry since mid-2007 is "stabilizing," Marine Harvest said in its 2009 sustainability report, released on Friday.
The world's largest farmed salmon producer attributed the effort to get ISA under control to a reduction in stocking density, implementation of strict sanitary measures and procedures, coordinated zone production and fallowing, improved husbandry and management, heightened surveillance and vaccination.
"Throughout the outbreak, we have maintained a transparent and open dialogue with the industry, sharing knowledge, experiences and practices to mitigate ISA effects on all stakeholders," said Marine Harvest in its report.
The ISA outbreak peaked in Chile in the fourth quarter of 2008. In 2009, the number of ISA cases leveled off nationwide. Marine Harvest experienced six cases of ISA last year, with only one outbreak each in the third and fourth quarters. By the end of 2009, Marine Harvest had experienced a total of 32 ISA cases since mid-2007, representing 23 percent of the 139 reported cases nationwide.
Marine Harvest's antibiotic use dropped 65 percent last year, to 13,644 kilograms, mainly due to a reduction in antibiotic use in Chile and Ireland, said the company. The company produced 359,639 metric tons (live weight) of salmon in 2009.
Also in its report, Marine Harvest promoted its effort, and the industry's effort, to reduce its feed conversion ratio (FCR), which it said now stands at approximately 2:1. The FCR, also called the fish-in-fish-out (FIFO) ratio, represents the amount of fishmeal required to produce 1 kilogram of fish.
"A key aspect in the sustainability of salmon aquaculture is the amount of wild fishmeal and fish oil contained within our feed supplies," said Marine Harvest. "In 1990, the wild fish-derived component of feeds could be as high as 60 percent. Today, following extensive research into fish nutrition, commercial feeds can be produced with only 15 percent fishmeal, without negative effects on the health and growth of the fish."
The report comes amid criticism from the environmental camp that salmon aquaculture's FCR is actually much higher than 2:1. The International Fishmeal and Fish Oil Organization puts the FCR at 1.7:1 and falling.
"This decrease [in the FCR] reduces the impact salmon aquaculture has on global fish stocks, which are threatened by overfishing," said Marine Harvest. "Since 2004, volumes of farmed Atlantic salmon have increased significantly in parallel with a significant reduction in utilized volumes of fishmeal and fish oil."
