Equine Vet News Folge 5

Titel:

Atypische Weidemyopathie

Beschreibung:

In dieser Folge besprechen Dr. Anja Gabe und Dr. Victoria Kratzmann die Klinik, Pathophysiologie und toxischen Ursachen der atypischen Weidemyopathie. Im Mittelpunkt stehen drei Studien aus dem Jahr 2o25: Assessment of tree- associated atypical myopathy risk factors in Acerpseudoplatanus(sycamore) seeds and leaves; González-Medina et al (2025) Equine Vet ; Unravelling Faecal Microbiota Variations in Equine Atypical Myopathy: Correlation with Blood Markers and Contribution of Microbiome; Francois et al (2025) Animals und In Vitro Investigation of Equine Gut Microbiota Alterations During Hypoglycin A Exposure¸Francois et al (2025) Animals

Klinische Symptome der Atypischen Weidemyopathie

  • Schwäche, Steifheit, Dyspnoe, Myoglobinurie, Festliegen
  • Mortalitätsrate bis 75%, in der Regel 72h nach Beginn der Symptome

Betroffen

  • Pferde mit 24h Weidegang ohne Zufütterung
  • Oft unter 3 Jahre alt und eher dünn
  • Vor allen im Herbst

Auslöser

  • Toxischer Metabolit des Hypoglycin A von Samen des Berg- oder Eschenahorn
  • Inhibierte Acyl-CoA-Dehydrogenasen dadurch Störung der beta-Oxidation
  • Betroffen ist der Energiestoffwechsel der Typ I Muskelfasern in Halte- und Atemmuskulatur

Therapie

  • symptomatisch

Einflussfaktoren auf die Hypoglycin A Konzentration

  • Hohe Variabilität der Konzentration der Samen bei einem Baum
  • Mechanische Zerkleinerung erhöht die Hypoglycin A Konzentration
    • Wärme (>4°C) und Feuchte steigern die Hypoglycin A Konzentration dieser beschädigten Samen
  • Geschädigte Samen können Wasser kontaminieren

Sonstiges

  • Intestinale Mikroflora ist in der Lage Hypoglycin A abzubauen
  • Hypoglycin A Konzentration kann im kontaminiertem Heu über Jahre verbleiben
  • Eine Intoxikation von Fohlen über Muttermilch oder transplazentar ist möglich

 

 

Quellen

Assessment of tree-associated atypical myopathy risk factors in Acer pseudoplatanus (sycamore) seeds and leaves; González-Medina et al. (2025) Equine Vet J  https://pubmed.ncbi.nlm.nih.gov/39865342/

Answers to the Frequently Asked Questions Regarding Horse Feeding and Management Practices to Reduce the Risk of Atypical Myopathy; Votion et al. (2020) Animals  https://pubmed.ncbi.nlm.nih.gov/32102384/

Unravelling Faecal Microbiota Variations in Equine Atypical Myopathy: Correlation with Blood Markers and Contribution of Microbiome; François et al. (2025) Animals  https://www.mdpi.com/2076-2615/15/3/354

In Vitro Investigation of Equine Gut Microbiota Alterations During Hypoglycin A Exposure François et al. (2025) Animals; https://www.mdpi.com/2076-2615/15/22/3343

Equine atypical myopathy: A metabolic study; Karlíková et al. (2016) The Veterinary Journal https://pubmed.ncbi.nlm.nih.gov/27687939/

Equine atypical myopathy caused by hypoglycin A intoxication associated with ingestion of sycamore maple tree seeds; Zuraw et al. (2026)

Atypical myopathy-associated hypoglycin A toxin remains in sycamore seedlings despite mowing, herbicidal spraying or storage in hay and silage; González-Medina et al. (2019) Equine Vet J — DOI: 10.1111/evj.13069

History and Clinical Features of Atypical Myopathy in Horses in Belgium (2000–2005); Votion et al. (2007) J Vet Intern Med — DOI: 10.1111/j.1939-1676.2007.tb03098.x

Hypoglycin A Concentrations in Seeds of Acer Pseudoplatanus Trees Growing on Atypical Myopathy-Affected and Control Pastures; Unger et al. (2014) J Vet Intern Med — DOI: 10.1111/jvim.12417

Seasonal pasture myopathy/atypical myopathy in North America associated with ingestion of hypoglycin A within seeds of the box elder tree; Valberg et al. (2012) Equine Vet J — DOI: 10.1111/j.2042-3306.2012.00564.x

Equine biochemical multiple acyl-CoA dehydrogenase deficiency (MADD) as a cause of rhabdomyolysis; Westermann et al. (2007) Molecular Genetics and Metabolism — DOI: 10.1016/j.ymgme.2007.05.009

Evidence-based therapy for atypical myopathy in horses; Fabius & Westermann (2018) Equine Vet Educ — DOI: 10.1111/eve.12895

Traditional and Quantitative Assessment of Acid-Base and Shock Variables in Horses with Atypical Myopathy; Galen et al. (2013) J Vet Intern Med — DOI: 10.1111/jvim.12156

The Story of Equine Atypical Myopathy: A Review from the Beginning to a Possible End; Votion (2012) ISRN Veterinary Science — DOI: 10.5402/2012/281018

Update on the Cause of Equine Atypical Myopathy; González-Medina (2015) Veterinary Record — DOI: 10.1136/vr.102891

Acquired multiple Acyl-CoA dehydrogenase deficiency in 10 horses with atypical myopathy; Westermann et al (2008) Neuromuscular Disorders, DOI: 10.1016/j.nmd.2008.02.007

Answers to the Frequently Asked Questions Regarding Horse Feeding and Management Practices to Reduce the Risk of Atypical Myopathy; Votion et al (2020) Animals; https://doi.org/10.3390/ani10020365

Atypical myopathy in grazing horses: A first exploratory data analysis; Votion et al (2008) The Vet J, https://doi.org/10.1016/j.tvjl.2008.01.016

Atypical myopathy in the South-East of England: Clinicopathological data and outcome in hospitalised horses; Dunkel et al (2020) Equine Vet Educ, https://doi.org/10.1111/eve.12895

Evidence-based therapy for atypical myopathy in horses; Fabius und Westermann (2018) Equine Vet Educ,  https://doi.org/10.1111/eve.12734

Management of cases suffering from atypical myopathy: Interpretations of descriptive, epidemiological and pathophysiological findings. Part 2: Muscular, urinary, respiratory and hepatic care, and inflammatory/infectious status; Galen und Votion (2013) Equine Vet Educ,  https://doi.org/10.1111/j.2042-3292.2012.00441.x

Traditional and Quantitative Assessment of Acid-Base and Shock Variables in Horses with Atypical Myopathy G. van Galen, https://doi.org/10.1111/jvim.12003

The Story of Equine Atypical Myopathy: A Review from the Beginning to a Possible End; Votion (2012) ISRN Vet Science;  https://doi.org/10.5402/2012/281018

Update on the cause of equine atypical myopathy; Gonzalez-Medina (2015) Vet Record; https://doi.org/10.1136/vr.h414

Traditional and Quantitative Assessment of Acid-Base and Shock Variables in Horses with Atypical Myopathy¸Galen et al (2013) J Vet Intern Med; https://doi.org/10.1111/jvim.12003

Verdacht auf Vergiftung durch Ahorn/Hypoglycin A Untersuchungsauftrag https://metabscreen.de/wp-content/uploads/PDF/Einsendeschein-Hypoglycin-A-Ver-1-2.pdf