Health Benefits of Yeast for Horses

Yeast is a single celled microorganism with over 1,500 species. The Saccharomyces cerevisiae strain of yeast is made up of several components that show benefits for the digestive health of horses, including:

  • beta glucan
  • mannan oligosaccharide
  • nucleotides

Beta Glucan in Yeast Protects the Equine GI Tract

Beta glucan derived from yeast:

  • protects the digestive system against harmful fungi
  • controls the dangerous toxins released by harmful fungi (called mycotoxins)

Beta glucan is extracted from the inner cell wall of the yeast Saccharomyces cerevisiae. It is a highly efficient mycotoxin adsorbent. As such, it works to minimize, decontaminate and thus control the toxicity produced by fungi and molds ingested with unavoidably contaminated forage and feeds.

Mannan Oligosaccharide Balances the Hindgut & Supports Immunity

Mannan oligosaccharide is a component of yeast that:

  • supports a balanced microflora
  • reduces the risk of infection
  • improves immune system response

Mannan oligosaccharide is extracted from the outer cell wall of Saccharomyces cerevisiae. Its primary role is the competitive blocking of bacterial lectins. Bacterial lectins have an affinity to bind with glycoproteins that are attached to the membrane of intestinal enterocytes (cells responsible for nutrient absorption). This is the first stage of infection.

Mannan mimics these intestinal glycoproteins, providing an alternative attachment site that competitively binds with pathogenic bacteria, rendering them unable to attach to the gut lining. Thus prevented from binding to the enterocytes, the bacteria are flushed from the system.

Mannan Oligosaccharides and Mare and Foal Immunity

Mannan oligosaccharides also aid immune response by enhancing plasma and colostral IgG and bile IgA antibody levels. These are central to the immunological link that occurs at birth when the mare transfers passive immunity to her foal. Transfer of immunity within the first 24 hours of the foal’s life is crucial for protection against pathogenic challenges, which may otherwise result in diarrhea, sepsis and even death.

Dietary Nucleotides Increase Growth of Enterocytes

Dietary nucleotides enhance the maturity and growth of normal enterocytes, the cells lining the gut and responsible for nutrient uptake and pathogen defense. Although the body can synthesize nucleotides de novo, the process uses more energy than scavenging them from dietary sources.

In addition to ongoing maintenance, cell division is critical for repairing damaged tissue, including ulcers. In times of stress or injury, dietary nucleotides may be indicated.

Yeast Components Help Maintain Digestive Health in Horses

These yeast components – beta glucan, mannan oligosaccharide and nucleotides – help obtain and maintain optimal digestive health for horses. The yeast extracts directly support the structure and functioning of the gut, while also facilitating better nutrient absorption, helping horses cope and thrive even in the face of modern feed and feed management routines.

Assess your horse’s health to determine if added digestive support may be beneficial for health and performance.


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