The effect of dietary camelina, flaxseed, and canola oil supplementation on skin fatty acid profile and immune and inflammatory responses in healthy adult horses.

This study investigated the effects of three types of oil—camelina, flaxseed, and canola—on the skin health and immune response of adult horses. The researchers observed that all three oils had similar effects, suggesting that camelina oil can be a viable alternative to the commonly used flaxseed and canola oils in equine diets.

Key Concepts

• The study is based on the premise that Camelina sativa, a crop rich in α-linolenic acid (ALA), offers resistance to severe climates and pests. This makes it a valuable resource for oil production.
• ALA is a type of n-3 fatty acid, which is known to be beneficial for health. Previously, it has been found that supplementing horse diets with oil from Camelina sativa has no adverse effects, and produces similar outcomes to flaxseed and canola oils in terms of skin and coat health.
• Using these previous findings as a foundation, this research aimed to evaluate the effects of camelina oil supplementation on the skin fatty acid profile and immune and inflammatory responses of adult horses, compared to flaxseed and canola oils.

Methodology

• For the experiment, 24 adult horses from two herds were chosen. A gradual 4-week period of fat acclimation followed by 16 weeks of dietary supplementation with either camelina, flaxseed, or canola oil was applied.
• Each oil was supplemented at a rate of 0.37 grams per kilogram body weight per day. The ALA content of the oils varied: ~34.9% in camelina, ~12.0% in canola, and 56.0% in flaxseed.
• Immune and inflammation responses of the horses were monitored by measuring antibody concentrations subsequent to sensitization with keyhole limpet hemocyanin (KLH) at weeks 10 and 12. Skin biopsy samples were taken at weeks 0, 8 and 16, and their fatty acid composition was determined using gas chromatography.

Findings

• The immune and inflammatory responses were not significantly different among the groups of horses fed different oils. Nor were treatment by time effects observed.
• Over time, most fatty acids in the skin altered in composition, with n-3 fatty acids increasing and n-6 fatty acids and the ratio of n-6 to n-3 fatty acids decreasing. The changes observed were regardless of the type of oil supplemented in diet.
• The only fatty acids that showed treatment specific effects were dihomo-γ-linolenic acid and the sum of n-3 fatty acids.
• By week 16, the composition of eicosapentaenoic acid in the skin was higher for horses fed flaxseed oil than those fed canola oil, but similar to the composition found in horses fed camelina oil.
• The observed small differences in n-3 fatty acid presence and n-6:n-3 ratio among the three oils suggest that all three oils could have a beneficial impact on skin fatty acid profile. However, the effects on the immune and inflammatory response of the horses were equivalent.

Conclusion

• The study concludes camelina oil may be a suitable alternative to flaxseed oil in terms of delivering ALA in equine diets. This is largely because camelina oil provides equivalent outcomes in terms of horse’s health parameters, skin and coat quality, immune response and inflammatory markers.
• However, it’s worth noting that these outcomes were observed with a controlled dose of 0.37 grams oil per kilogram body weight. Different outcomes may be observed with different dosages or long-term usage.