Duration of effects of dietary fish oil supplementation on serum eicosapentaenoic acid and docosahexaenoic acid concentrations in dogs

Abstract

Objective - To determine how long serum concentrations of ω-3 fatty acids remain elevated after cessation of dietary fish oil supplementation. Animals - 12 healthy Beagles. Procedure - Baseline serum concentrations of linoleic acid, linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were measured. Dogs were then fed a diet supplemented with soybean oil or fish oil for 8 weeks, and serum fatty acid concentrations were measured while dogs were fed the experimental diets and for 18 weeks after they were switched to a maintenance diet. Results - For dogs fed the fish oil diet, serum EPA and DHA concentrations were significantly increased by week 1 and remained increased for 7 (DHA concentration) or 3 (EPA concentration) weeks after dietary fish oil supplementation was discontinued. Conclusions - In dogs, supplementation of the diet with fish oil may have effects for several weeks after dietary supplementation is discontinued. Clinical Relevance - Studies of the effects of fish oil supplementation that use a crossover design should allow for an appropriate washout period.