Saccharomyces products – which one do I feed?
Mycosorb A+ or Diamond V XPC, do they do the same job?
First of all, what is Saccharomyces cerevisiae?
Saccharomyces cerevisiae is a single-celled eukaryote (yeast/fungi – brewers yeast) that is frequently used in scientific research and has many applications. The advantages are that its genome has been sequenced, its genetics are easily manipulated, and it is very easy to maintain in a lab. Historically it was mainly used in the production of food and winemaking and is believed to have been originally isolated from the skin of grapes. Studies with S. cerevisiae have contributed to our understanding of important cellular processes such as the cell cycle, aging, and cell death, protein purification and the study of DNA repair mechanisms and other cellular processes related to Alzheimer’s and Parkinson’s diseases.
I’m not sure of the exact number but there are so many products that are made from Saccharomyces cerevisiae and they all have different jobs, as they are different strains. The difference can come from the different substrates for the fermentation by S. cerevisiae, what these ‘critters’ are fed. Some are patented like Diamond V XPC (Diamond V) and Mycosorb A+ (Alltech Inc). Diamond V XPC is a prebiotic which means food for gut microbes, to boost their populations. Mycosorb A+ is a fungal toxin binder. These two products, even though it’s the same species of yeast, they are not the same as they are different patented strains.
The Medina et al study showed that S. cerevisiae strain/preparation helped prevent colonic acidosis in horses on crazy high grain diets. The Newbold et al study on S. cerevisiae showed how different strains were effective for sheep.
So to sum up, the different strain or type of S. cerevisiae product can have different jobs/activities.
Do you need these products?
Yes to Mycosorb A+ if you are concerned about your hay being mouldy or are experiencing a fungus outbreak in your pasture, for example, Paspalum ergot fungus or certain strains of endophyte perennial Rye grass, consider a toxin binder. These plants and others are renowned for causing photosynthesisation, signs are sunburn and blistering on pink skin on faces and pasterns (generic term, greasy heel or mud fever). When an animal consumes a plant or chemical containing these pigments (eg. polyphenolic), the pigments circulate to the skin where they are exposed to UV light, fluoresce and cause oxidative injury to the cells of the skin. Liver damage in a horse might not be noticed until the animal develops photosensitisation.
There are clay type toxin binders available based on bentonite or zeolite but the major disadvantage is that they are known to bind minerals like copper and zinc. This is why vets may recommend short term use if your horse has acute infectious diarrhoea, may prevent intestinal absorption of toxic minerals. Best to consult your vet. Another disadvantage is these clay based products are very high in iron (dirt in a bucket). Montmorillonite is the primary clay type in bentonite. An example of a study looking at this was done by Tomasevic-Canovic et al, link below.
Zeolite can absorb aflatoxin but *not* other toxins. It can absorb molecular minerals with a positive charge but they must be in dissolved form and it will bind the nutritionally important minerals as well as toxins.
Diamond V XPC is a prebiotic, supporting the growth of intestinal bacteria as it’s used as a food source. If your horse is exhibiting a hay or grass belly OR have a degree of diarrhoea then Diamond V XPC may well help. The XPC means it’s 4x more concentrated than Diamond V. Best to consult your vet as there are veterinary conditions that cause diarrhoea.
What is brewer’s yeast?
Brewer’s yeast, what you can often buy cheaply at stockfeed suppliers is known as ‘spent’ S. cerevisiae. When sold as a dietary supplement it is typically spent/dead and fed primarily for B vitamins.
Note: If your horse has robust gut function and is not on a crazy high grain intake then probably not necessary to consider B vitamin supplementation as horses gain B vitamins from what they eat (grass/hay) and gut microbes produce all the B vitamins. The best source is green grass.
Some examples of research.
Links may change over time. If a link doesn’t work, search the title in your search engine.
Coverdale JA (2016) Horse Species Symposium: Can the microbiome of the horse be altered to improve digestion? J. Anim. Sci. Jun;94(6):2275-2281
Medina B, Girard ID, Jacotot E and Julliand V (2002) Effect of a preparation of Saccharomyces cerevisiae on microbial profiles and fermentation patterns in the large intestine of horses fed a high fiber or a high starch diet J. Anim. Sci. Oct;80(10):2600-2609
Nerlich HK, Koler R, Powell E and Williams TL (2018) 498 Saccharomyces cerevisiae supplementations effect on fiber digestibility in equine J. Anim. Sci. Apr;96(2):266
Newbold CJ, Wallace RJ, Chen XB and McIntosh FM (1995) Different strains of Saccharomyces cerevisiae differ in their effects on ruminal bacterial numbers in vitro and in sheep J. Anim. Sci. Jun;73(6):1811-1818
Tomasevic-Canovic M, Dakovic A, Markovic V and Stojsic D (2001) The effect of exchangeable cations in clinoptilolite and montmorillonite on the adsorption of aflatoxin B1 I. Tech. Nuc.