Kentucky Equine Research EO-3 Review: Marine Omega-3 for Horses

The omega-3 supplement with the better evidence behind it, and the one your horse is most likely to refuse.

The verdict: A marine-derived oil supplying DHA and EPA directly, which is the form of omega-3 with the strongest research support in horses, in a gallon that lasts a long time. Buy it if you are supplementing for inflammatory support rather than for a shiny coat. Skip it if palatability is likely to be a fight, because a supplement the horse will not eat is worth nothing and flax is far easier to feed.

Specifications

Specifications above come from Kentucky Equine Research's published product information. Treat pricing as approximate, since Amazon pricing moves.

What it does well

• It supplies EPA and DHA directly, so the horse does not have to convert plant ALA, which it does inefficiently. That is the single technical reason to choose marine over flax.
• Kentucky Equine Research publishes equine nutrition research rather than only marketing copy, which is unusual in this category and worth something when judging a claim.
• A gallon at the usual feeding rates lasts a long time, so the cost per day is lower than the sticker suggests.
• Liquid mixes into feed rather than sitting on top of it as a powder a fussy horse can eat around.
• Relevant to metabolic management as well as inflammation, given KER's stated effects on glucose tolerance, which is worth raising with your vet if your horse is insulin dysregulated.

Where it falls short

• Fish oil smells like fish oil. Some horses refuse it outright, and introducing it gradually over a week or two is the difference between success and a wasted gallon.
• Marine oils oxidise. Keep it sealed, out of sunlight and cool, use it within a sensible period once opened, and throw it out if it smells sharp rather than fishy. Rancid oil is pro-inflammatory, which is the opposite of the point.
• The claims here are the manufacturer's. Positive effects on glucose tolerance and inflammatory conditions are plausible and researched in various species, and the size of the effect in your individual horse is not something a bottle can promise.
• It adds fat and therefore calories, which needs weighing on an overweight horse.
• It costs several times what flax costs per unit of omega-3, and if your goal is a better coat that premium buys you very little.

What owners report

The recurring theme in published owner reports is palatability, split roughly into horses that take it without noticing and horses that will not touch feed it has been near. Owners who introduced it slowly report better outcomes than those who poured a full dose over dinner on day one.

Where owners report a benefit, it is most often described for horses with allergic or inflammatory skin conditions and for older horses in work. Reports of coat improvement exist too, which is unsurprising, and it is a very expensive way to buy coat shine when flax does that job.

Who it suits

• Horses being supplemented specifically for inflammatory support, on a vet's advice.
• Metabolic horses whose vet has raised omega-3 as part of the plan.
• Owners who have tried flax and want the better-absorbed form.

Who should skip it

• Anyone whose goal is coat condition, where flax does the same job for far less. Our flax versus fish oil comparison sets out the difference.
• Very fussy eaters, unless you are prepared to introduce it over two weeks.
• Anyone without cool, dark storage, since oxidised marine oil is worse than no supplement.

Alternatives worth considering

Keep reading

• Flax vs fish oil for horses
• Natural vs synthetic vitamin E
• Best omega-3 supplements
• Omega Horseshine review

This review draws on published specifications, manufacturer figures and the consensus of verified owner reviews. We have not tested this product ourselves, and we say so rather than implying otherwise. As an Amazon Associate we earn from qualifying purchases.