| Summary: | The Arctic charr (Salvelinus alpinus) is a top predator in northern lakes and accumulates persistent lipophilic contaminants. Toxaphene, a major organochlorine contaminant in Arctic charr, is known to be acutely toxic to fish but the effects of dietary exposure have not been examined. Furthermore, lake-resident Arctic charr are frequently infected with larvae of the cestode, Diphyllobothrium dendriticum. The objective of this study was to investigate the effects of toxaphene exposure on Arctic charr growth, nutritional quality, physiology, and susceptibility to infections of D. dendriticum. A preliminary experiment found no effect of toxaphene on charr visceral organ and fat weights, plasma Vitamin A and E and plasma cortisol, although dominance hierarchies within groups may have masked treatment effects. For the main experiment, hatchery-reared Arctic charr were subjected to one of four treatments: (i) a single oral dose of corn oil (control); (ii) a single oral dose of 10 mug/g wet weight toxaphene dissolved in corn oil; (iii) exposure to 15 larval D. dendriticum; and (iv) a combination of both. (Abstract shortened by UMI.)
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