The horse is our sport and leisure partner. Physical activity and exercise are healthy and benefit both us and the horses. But why do many horses have such a hard time with it?

Recurring lameness without an identifiable cause, muscle tension, visible dents in the musculature up to symptoms similar to a Equine Rhabdomyolysis – in these cases, not only the performance, but especially the well-being of the horse is seriously impaired. Diseases of muscle metabolism can be found throughout the entire horse population. The correct feeding management along with the specific nutrient supply is crucial for a horse’s life free of complaints.

We are happy to inform you about equine myopathies and the problems of PSSM 1 and PSSM 2. Our focus lies on muscle metabolism, symptoms, diagnostics and, in particular, technical feeding solutions and suitable products.

Visualization of the variants in a graphic

© St. Hippolyt | Digital Marketing

© St. Hippolyt | Digital Marketing


Equine Myopathies – PSSM 1 und PSSM 2

PSSM is a collective term or synonym for various forms of genetic myopathies, i.e. muscle metabolic disorders. PSSM stands for polysaccharide storage myopathy, whereby only type 1 (P1) actually describes a actual storage myopathy. Other forms of myopathy are summarised under the synonym “PSSM 2”, since at the beginning of research it was also considered to be a storage myopathy. Nowadays, it is known that “PSSM 2” includes different muscle disorders, with different variants. It is likely that there are other, hitherto undiscovered variants of equine myopathies.

However, what PSSM 1 and PSSM 2 do have in common is their symptomatic nature and the crucial influence proper feeding management plays on the performance and, above all, the well-being of the horse.
Although this condition cannot be cured due to its genetic anchoring, feeding and management are the deciding factors for a painful existence or a life free of symptoms for the horse.


Online seminar on musculature & PSSM

In our online seminar on 28 September 2021 by St. Hippolyt and WES for horses, we specifically address the problems of PSSM 1 and “PSSM 2”. The focus hereby lies on the muscle metabolism, the symptoms, diagnostics and above all technical feeding solutions incl. product presentation.

1.Topic: The Musculature
2.Topic: PSSM 1 and “PSSM 2
3.Topic: Adapted feeding for PSSM

Recording and podcast can be found on the following channels:

HippoWissen Feeding Seminar: Musculature and PSSM – YouTube


Presentation on PSSM 2

  • PSSM2 is a genetic mutation with increasing significance and affects all breeds.
  • PSSM2 is a metabolic disorder of the muscle cell, which is not caused by glycogen storage – in other words, sugar-dependent – as in PSSM1, but triggers structural defects in the muscle cell, which require a constant supply of protein for repair.
  • At present, six genetic defects can be tested via DNA examinations using hair roots (P2,P3,P4,P8,K1 and PX).
  • Due to the complicated mode of inheritance, even a single altered gene can lead to problems, but the likelihood that a horse will show symptoms increases with the number of altered genes. However, there are also carriers who do not develop any symptoms at all.
  • More than 50% of warmbloods appear to carry at least one altered gene. By mating them, we unknowingly are breeding an increasing number of double and multiple carriers that develop symptoms very frequently.
  • Usually, symptoms are only observed from the age of 6, but they are also possible in foal age.
  • Symptoms are stiffness, tension, unwillingness to move, muscle hardening, muscle depressions, bumps and fissures, saddle pressure, unclear lameness, poor muscle tone, protruding spine, breathing noises without sound, extreme sensitivity, susceptibility to touch, nervousness, unwillingness to be saddled and groomed, and many others.
  • Due to proper management, many horses can be maintained symptom-free or at least symptom-poor.
  • A grain-free and protein-rich diet, sufficient exercise and training to build up muscles, a supply of essential amino acids, antioxidants and vitamins and trace elements that are important for muscle metabolism contribute to keeping a horse symptom-free.

If you have any questions or need advice, please do not hesitate to contact us !

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