Linseed (Micronised) (Linum usitatissimum)
Linseed, aka flaxseed, is one of the oldest crops, having been cultivated since the beginning of civilization. It's latin name, Linum usitatissimum, means 'very useful' ;-)
100% Linum usitatissimum (Linseed), micronised
Why feed fatty acids?
Micronised linseed comes in at the same omega-3 profile as fresh, growing grass, so horses not on fresh grass will have a dietary deficiency of omega-3.
Here's the science - the horse’s natural diet of grass has an omega-3 to omega-6 fatty acid ratio of around 4:1, similar to other browse foods like leaves and buds, with summer growing grass coming in at around 4% fat, with 75% omega-3 as alpha-linolenic acid.
This level of intake isn't seasonally available all year, so outside of the growing grass period, or if a horse is on a hay-only diet, a study reported at the Equine Science Society showed via blood tests that 100g/day of linseed equals the same daily omega-3 intake as a horse on pasture – this applies to the average 500kg horse, so pro-rata it works out at 20g/100kg bodyweight.
NB - when grass is dried and baled as hay, the fragile omega-3 fatty acids are lost so it definitely needs to be fed.
Here’s a feed-rate guideline :
- If your horse is on part grass/part hay (say, overnight), then feed 10g/100kg bodyweight daily.
- If your horse is on a full hay diet with no grass, or during winter, feed 20g/100kg bodyweight daily.
- If your horse is permanently on growing grass during the summer, there's no need to feed linseed until winter.
For the record, micronised linseed meal is a staple in my feedroom - I can’t recommend it highly enough for its high-nutrient benefits for condition, coat shine, joint comfort, hooves and itchy skin to name just a few.
It’s also a gut system superstar. Thanks to its high soluble-fibre level (around 27%) this makes it high in mucilage, so super-lubricating for sensitive guts. Micronization itself also beneficially changes the structure of the seed’s grain which greatly increases digestibility in the small intestine by up to 90%. This reduces the burden on the large intestine and can reduce the risk of overloading the GI tract and hence reduce the risk of colic, laminitis and acidosis.
Studies also show that feeding linseed meal generates better glucose control and higher levels of beneficial fatty acids.
"Data suggests that linseed fibre supplementation affects host metabolism by increasing energy expenditure and reducing obesity as well as by improving glucose tolerance. Future research should be directed to understand relative contribution of the different microbes and delineate underlying mechanisms for how linseed fibers affect host metabolism." http://www.the-aps.org/mm/hp/Audiences/Public-Press/2019/5.html
However, we probably best know linseed for its high omega fatty-acid content, with the low-heat micronisation process preserving them.
There are two classes of fatty acids (the building blocks of fats) that must be in the diet for optimal immune function, Omega 3, the non-inflammatory Alpha Linolenic Acid (ALA) and Omega 6, the pro-inflammatory Linoleic Acid (LA).
The immune system uses them to synthesise signalling molecules; omega-6 EFAs arepredominately made into inflammatory signals while the omega-3s are anti-inflammatory. Both are required for robust immune reactions.
It’s also an excellent protein supplement at around 25%, with key amino-acids (the building blocks of protein) in its profile, including the most commonly deficient amino acid, lysine, and even higher levels of leucine, the most common amino acid in skeletal muscle. It’s also a good source of methionine, the sulphur-containing amino acid beneficial for strong hooves.
Linseed Meal v. Linseed Oil
I always recommend using micronissed whole linseed meal as linseed meal is a whole food, whereas the extracted oil is not, and is both delicate and easily oxidized. Equally, evolution has made the horse's sensitive gut system such that it struggles to digest any extra fat over and above the grass ration, so adding extra liquid oil to the feedbowl can significantly disrupt the digestive process. See our webpage in our 'Feeding our Horses' section, Why we should never add liquid oil to the feedbowl, for the full story.
A tablespoon of linseed grain contains 2.35 grams alpha-linolenic acid (ALA), and as linseed is a whole food it also contains a host of other nutrients that are not included in its extracted oil.
For example, linseed is a rich source of dietary fibre, and nutrient-rich with an excellent source of minerals and vitamins such as calcium, copper, magnesium, folate and vits E, K, C and several B's.
Let's talk Lignans
Linseed is also the richest known source of plant lignans, which have been found to have hormone-balancing and cardiovascular benefits.
Lignans are converted by the microbiome to enterolignans (enterodiol and enterolactone). Also called mammalian lignans, these enterolignans perform a variety of beneficial biological activities including anti-inflammatory and apoptosis effects that have an influence on disease. When diets have been supplemented with linseed, it substantially increases the formation of enterolactone in the gut.
In another human study evaluating gut microbiota metabolites of dietary lignans, researchers discovered the presence of enterolactone was highly connected with a lower risk of Type 2 diabetes, which directly relates to IR development in our horses.
High levels of lignans also play a significant role in blocking the effects estrogen may have in producing estrogen-driven cancers. Research also shows phytoestrogens' effect on the bone can help maintain mineral density. Clinical Endocrinology 2002;56(3):321
While some linseed oils have lignans added back to them, the resulting product is still different from its natural, whole-food form.