Micronized 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, linseed is best known 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 and omega-6, with omega-3 contributing to normal homeostatic balancing of inflammation, as well as supporting vision, the nervous system and cellular membrane integrity. Linseed comes in at around 30%+ healthy fat, with the same high omega-3 profile as fresh grass.
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.
So Why feed fatty acids?
Horses not on fresh grass will have a dietary deficiency of omega-3. The horse’s natural diet, grass, has an omega-3 to omega-6 fatty acid ratio of around 4:1, similar to other browse foods like leaves and buds. When grass is dried and baled as hay, the fragile omega-3 fatty acids are lost, which means ... horses not on fresh grass will have a dietary deficiency of omega-3.
The immune system uses them to synthesise signalling molecules, as in omega-6 fatty acids predominately are made into inflammatory signals while the omega-3 are anti-inflammatory. Both are required for robust immune reactions.
The general rule of thumb is to feed 20g/100kg bodyweight summer, and double this in winter, so for an average 500kg horse you’re looking at 100g/day summer and 200g/day winter - for horses with loss of weight/condition you can easily double this. If there’s high hay content in the diet, the omegas naturally denature during the curing process, so feed as per winter rations.
Linseed Meal v. Linseed Oil
I always recommend using whole linseed meal as linseed meal is a whole food, whereas the extracted oil is not, and is both delicate and easily oxidized.
Linseed provides a concentrated source of omega-3 fatty acids, specifically alpha-linolenic acid (ALA), the building block for all omega-3’s. While the oil contains more ALA than the grain (1-tbsp linseed grain contains 2.35 grams while 1-tbsp oil contains 7.25 grams), the grain is a whole food and therefore 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 intestinal microbes to enterolignans (enterodiol and enterolactone).
Also called mammalian lignans, these enterolignans perform a variety of beneficial biological activities including anti-inflammatory and apoptotic effects that have an influence on disease. When diets have been supplemented with flaxseed, 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 associated with a lower risk of Type 2 diabetes, which directly relates to the 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.
Think of linseed meal and linseed oil as unique products in their own right and not as one being a substitute for the other. Linseed will provide an array of different nutritional benefits into the diet with the oil more as a dietary supplement to boost Omega-3 intake.