When salmon farming first started in Europe, the fish often became infested with lice, which then spread to wild fish.

当鲑鱼养殖在欧洲开始的时候，这种鱼经常伴随着虱子大量滋生，随后虱子又蔓延到野生鱼上。

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Studies by local and Norwegian scientists have found that sea lice and other parasites from the fish farms can infect the passing sockeye, reducing their chance of survival.

加拿大和挪威科学家都已经发现，来自渔场的海虱和其他寄生虫能感染经过的红鲑，导致红鲑的生存机率下降。

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Salmon grown in large farms like Norway's are especially susceptible to sea lice, which are anincreasing menace to anyone trying to make a living farming fish.

在大型养植场养植的鲑鱼，如在挪威的养殖场，特别容易遭到海虱的浸害，这也越来越要挟到养鱼为生的人。

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Critics are concerned about the levels of sea lice at farms which can be passed on to passing wild fish and are particularly harmful to juvenile fish.

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