Brewer's Yeast.
Why Okapi does not use brewer's yeast in its products and why we (Equine Naturelle) do not sell brewer's yeast.
Brewer's yeast is produced in the beer making process in the brewing industry, because it gives beer what makes it attractive to most people:
it converts sugar into alcohol.
Like spent grains, yeast is a waste product that remains at the end of the process. Brewer's yeast is therefore produced in large quantities each year and can therefore be bought cheaply by feed manufacturers and then sold at a high price in elegant packaging.
Before being used as animal feed, brewer's yeast is dried (which inactivates it, but does not necessarily kill it) and sold as is.
Depending on the drying process, brewer's yeast can go through "survival stages" and thus withstand adverse conditions such as drought for years. When the brewer's yeast cells return to positive living conditions (warmth, moisture, nutrients), they "wake up" again and resume their metabolism.
The horse's large intestine is ultimately a large fermentation organ that offers optimal conditions for micro-organisms: heat, moisture, nutrients.
Brewer's yeast find the best conditions here and can, among other things, use the components of the carbohydrates that are formed during the digestion process or the starch that is brought in from the small intestine, which can produce alcohol as a by-product.
Although a slightly alcoholic horse may appear to be more relaxed at first sight (which may result in improved defecation due to stress), this is not desirable in the long term, especially as alcohol overtaxes the liver.
Furthermore, studies have shown that brewer's yeast feed does not improve fibre digestion(1), as is often claimed, and that it is not part of the natural (wild) microbiome of horses in the large intestine(2). Since our concept places particular emphasis on a healthy large intestine microbiome, brewer's yeast therefore fails completely in terms of "digestion promotion" or "probiotic".
The use of brewer's yeast in the fattening of pigs and cattle as a "fattening accelerator" - i.e. for faster weight gain in order to reach slaughter weight - should also give pause for thought as to whether it is such an ideal food for our horses, which already suffer quite often from overweight and its health consequences.
In recent years, brewer's yeast has become very popular in horse feed as a so-called miracle food.
Unfortunately, the marketing promises do not take into account the scientific reality.
That is why we do not use brewer's yeast at all.
Dr. Christina Fritz, Okapi
(1) DOI: 10.1016/j.livsci.2015.11.023
(2) DOI: 10.1055/a-0824-5210