title: Hypoglycin A concentrations in seeds of Acer pseudoplatanus trees growing on atypical myopathy-affected and control pastures.
abstract: BACKGROUND
  Hypoglycin A, found in seeds of Acer negundo, appears to cause seasonal pasture myopathy (SPM) in North America and is implicated in atypical myopathy (AM) in Europe. Acer negundo is uncommon in Europe. Thus, the potential source of hypoglycin A in Europe is unknown.
  
  
  OBJECTIVE
  We hypothesized that seeds of Acer pseudoplatanus were the source of hypoglycin A in Europe. Our objective was to determine the concentration of hypoglycin A in seeds of A. pseudoplatanus trees located in pastures where previous cases of AM had occurred.
  
  
  METHODS
  None.
  
  
  METHODS
  University of Berne records were searched to retrospectively identify 6 farms with 10 AM cases and 11 suspected AM deaths between 2007 and 2011. During October 2012, A. pseudoplatanus seeds were collected from 2 to 6 trees per pasture on 6 AM farms (7 pastures) from trees in or close to 2 pastures on 2 control farms where AM had not been previously reported. Hypoglycin A in seeds was analyzed by GC-MS.
  
  
  RESULTS
  Acer pseudoplatanus trees were identified on all AM pastures. Hypoglycin A was detected in all A. pseudoplatanus seeds in highly variable concentrations ranging from 0.04 to 2.81 μg/mg (mean 0.69) on AM farms and 0.10 to 9.12 μg/mg (mean 1.59) on control farms.
  
  
  CONCLUSIONS
  Preventing horses from grazing pastures containing A. pseudoplatanus seeds during late fall and early spring might be the best means to prevent AM.
authors.affiliation: Division of Clinical Veterinary Medicine, Suisse Institute for Equine Medicine (ISME), Vetsuisse Faculty, ALP Haras, University of Bern, Bern, Switzerland.
authors.forename: L
authors.initials: L
authors.lastname: Unger
authors.forename: A
authors.initials: A
authors.lastname: Nicholson
authors.forename: E M
authors.initials: EM
authors.lastname: Jewitt
authors.forename: V
authors.initials: V
authors.lastname: Gerber
authors.forename: A
authors.initials: A
authors.lastname: Hegeman
authors.forename: L
authors.initials: L
authors.lastname: Sweetman
authors.forename: S
authors.initials: S
authors.lastname: Valberg
mesh_terms: D031002:Acer / Q000737:chemistry*; D000822:Animal Husbandry; D000818:Animals; D006734:Horse Diseases / Q000139:chemically induced*; D006736:Horses; D007005:Hypoglycins / Q000032:analysis* / Q000633:toxicity; D009135:Muscular Diseases / Q000139:chemically induced / Q000662:veterinary*; D012206:Rhabdomyolysis / Q000139:chemically induced / Q000662:veterinary; D012639:Seeds / Q000737:chemistry*
chemical_list: D007005:Hypoglycins; C041757:hypoglycin
keywords: Lipid; Multiple acyl-CoA dehydrogenase deficiency; Rhabdomyolysis