Effects of dietary supplementation with fish oil on in vivo production of inflammatory mediators in clinically normal dogs

Am J Vet Res. 2008 Apr;69(4):486-93. doi: 10.2460/ajvr.69.4.486.


Objective: To evaluate the effect of diets enriched with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on in vivo production of interleukin (IL)-1, IL-6, tumor necrosis factor (TNF)-alpha, prostaglandin E2 (PGE2), and platelet-activating factor (PAF) in dogs.

Animals: 15 young healthy dogs.

Procedures: Dogs were randomly allocated to receive an isocaloric ration supplemented with sunflower oil (n=5), fish oil (5), or fish oil plus vitamin E (5) for 12 weeks. At week 12, in vivo production of inflammatory mediators was evaluated in serum at multiple time points for 6 hours following stimulation with IV administration of lipopolysaccharide (LPS).

Results: Serum activity or concentration (area under the curve) of IL-1, IL-6, and PGE2 significantly increased after LPS injection in all groups but to a lesser extent in dogs receiving the fish oil diet, compared with results for dogs receiving the sunflower oil diet. Serum activity of TNF-alpha and PAF concentration also increased significantly after LPS injection in all groups but did not differ significantly among groups.

Conclusions and clinical relevance: A fish oil-enriched diet consisting of 1.75 g of EPA/kg of diet and 2.2 g of DHA/kg of diet (dry-matter basis) with an n-6:n-3 fatty acid ratio of 3.4:1 was associated with significant reductions in serum PGE2 concentrations and IL-1 and IL-6 activities. Results supported the use of EPA- and DHA-enriched diets as part of antiinflammatory treatments for dogs with chronic inflammatory diseases. Additional studies in affected dogs are warranted to further evaluate beneficial anti-inflammatory effects of EPA- and DHA-enriched diets.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Area Under Curve
  • Cytokines / biosynthesis*
  • Cytokines / blood
  • Dietary Supplements
  • Dinoprostone / biosynthesis
  • Dinoprostone / blood
  • Docosahexaenoic Acids / administration & dosage*
  • Dogs / blood
  • Dogs / immunology*
  • Eicosapentaenoic Acid / administration & dosage*
  • Female
  • Interleukin-1 / biosynthesis
  • Interleukin-1 / blood
  • Interleukin-6 / biosynthesis
  • Interleukin-6 / blood
  • Male
  • Platelet Activating Factor / biosynthesis
  • Random Allocation
  • Tumor Necrosis Factor-alpha / biosynthesis
  • Tumor Necrosis Factor-alpha / blood
  • Vitamin E / administration & dosage


  • Cytokines
  • Interleukin-1
  • Interleukin-6
  • Platelet Activating Factor
  • Tumor Necrosis Factor-alpha
  • Vitamin E
  • Docosahexaenoic Acids
  • Eicosapentaenoic Acid
  • Dinoprostone