Metabolism of alpha-linolenic acid from flaxseed in dogs

Effects of dietary camelina, flaxseed, and canola oil supplementation on transepidermal water loss, skin and coat health parameters, and plasma prostaglandin E2, glycosaminoglycan, and nitric oxide concentrations in healthy adult horses

Camelina oil is derived from a low-input, high-yield crop and, in comparison to many other dietary fat sources currently used in equine diets, provides a greater amount of α-linolenic acid [ALA; (n-3)], than linoleic acid [LA; (n-6)]. However, no research exists assessing the effects of feeding camelina oil to horses in contrast to other commonly used oils. The objective of this study was to compare the effect of supplementing camelina oil to that of flaxseed and canola oil supplementation, on outcomes related to skin and coat health in horses. Thirty adult horses [23 mares, 7 geldings; 14.9 years ± 5.3 years; 544 ± 66 kg body weight (BW) (mean ± SD)] underwent a 4-week wash-in period consuming hay and sunflower oil. Following the wash-in period, horses were blocked by location, age, and BW, and assigned to one of three treatment oils for 16 weeks (370 mg oil/kg BW): camelina (CAM), canola (OLA), or flaxseed (FLX) oil. Blood samples were collected and plasma prostaglandin E2 (PGE2; ELISA), nitric oxide (NO; Griess Reaction), and glycosaminoglycan (GAG; DMMB) concentrations were measured on weeks 0 (n = 30), 14 (n = 24), and 16 (n = 30). On weeks 0, 2, 4, 8, and 16, transepidermal water loss (TEWL) was measured pre- and post-acetone application using a VapoMeter (n = 26), and a 5-point-Likert scale was used to assess skin and coat characteristics on the side and rump of the horses (n = 30). All data were analyzed with repeated measures ANOVA using PROC GLIMMIX in SAS. Independent of treatment, coat color, and quality increased from baseline. There were no differences in the outcomes assessed between the horses supplemented camelina oil and those supplemented canola or flaxseed oil. These results suggest that independent of treatment, all oil supplements improved coat color and quality in horses. This provides indication that camelina oil is comparable to existing plant-based oil supplements in supporting skin and coat health and inflammation in horses.

A prospective, randomized, double blind, placebo-controlled evaluation of the effects of eicosapentaenoic acid and docosahexaenoic acid on the clinical signs and erythrocyte membrane polyunsaturated fatty acid concentrations in dogs with osteoarthritis

BACKGROUND

Osteoarthritis (OA) in dogs is a prevalent and serious condition. The most common treatment for the clinical signs of OA in dogs is the administration of nonsteroidal antiiflammatory pharmaceuticals. Omega-3 (n-3) fatty acids have been shown to reduce the clinical signs of osteoarthritis in dogs.

OBJECTIVE

The primary goals of this study were 1) to determine the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the clinical signs of OA in dogs, 2) to evaluate the effects of supplementation on the arachadonic acid (ARA)/ (EPA+DHA) algorithm and 3) to correlate alterations in the ARA/(EPA+DHA) with changes in the clinical signs of canine OA.

METHODS

Seventy-eight client owned dogs were enrolled in a prospective, randomized, double-blind, placebo controlled clinical trial. Dogs were randomized to placebo oil or triglyceride n-3 oil (providing an average dose of 69mg EPA+DHA/kg/day). Orthopedic examinations and blood analyses were performed at baseline, day 42, and day 84. A single investigator confirmed a diagnosis of OA of the coxofemoral joints and/or stifle joints in all dogs.

RESULTS

Seventy-four dogs completed the trial. All clinical outcomes for measuring discomfort, lameness, and joint severity at day 84 and all blood metrics at day 42 and day 84 significantly (p<0.05) improved compared with placebo. No major side effects were observed.

CONCLUSION AND CLINICAL RELEVANCE

This study demonstrated that the daily supplementation of a dogs diet with EPA and DHA shifts the blood fatty acid concentrations correlating to relief of clinical signs associated with OA in dogs.

Plasma and skin concentrations of polyunsaturated fatty acids before and after supplementation with n-3 fatty acids in dogs with atopic dermatitis

OBJECTIVE

To determine essential fatty acid concentrations in plasma and tissue before and after supplementation with n-3 fatty acids in dogs with atopic dermatitis.

ANIMALS

30 dogs with atopic dermatitis.

PROCEDURE

Dogs received supplemental flaxseed oil (200 mg/kg/d), eicosapentaenoic acid (EPA; 50 mg/kg/d)-docosahexaenoic acid (DHA; 35 mg/kg/d), or mineral oil as a placebo in a double-blind, placebo-controlled, randomized trial. Clinical scores and plasma and cutaneous concentrations of linoleic acid, arachidonic acid, alpha-linolenic acid (alpha-LLA), EPA, DHA, prostaglandin E2, and leukotriene B4 were determined.

RESULTS

Total plasma concentrations of alpha-LLA and EPA increased and those of arachidonic acid decreased significantly with administration of EPA-DHA, and concentrations of alpha-LLA increased with flaxseed oil supplementation; nevertheless, there was no significant change in the concentrations of these fatty acids or eicosanoids in the skin. There was no correlation between clinical scores and plasma or cutaneous concentrations for any of the measured fatty acids or eicosanoids.

CONCLUSION AND CLINICAL RELEVANCE

Results indicated that at the dose used, neither the concentrations of fatty acids in skin or plasma nor a decrease in the production of inflammatory eicosanoids was a major factor involved in the mechanism of action in dogs with atopy that responded to fatty acid supplementation.