title: Prevalence and risk factors for hyperinsulinaemia in ponies in Queensland, Australia.
abstract: OBJECTIVE
  To determine the prevalence of hyperinsulinaemia in a population of ponies in Queensland, Australia, and identify associated factors.
  
  
  METHODS
  Breeders or traders of ponies within a 100 km radius of Gatton, Queensland, were recruited for study using an internet database. Clinical and management details were obtained, including body condition score, fat deposition and history or evidence of laminitis. Blood samples were analysed for serum insulin and triglyceride concentrations and plasma adrenocorticotrophic hormone (ACTH) and leptin concentrations following short-term removal from pasture and withholding of supplementary food for at least 12 h.
  
  
  RESULTS
  Of 23 pony studs identified, 22 were available for visit. The study population consisted of 208 ponies: 70 Australian Ponies; 67 Welsh Mountain Ponies or Cobs; 51 Connemara Ponies; 20 Shetland ponies. We excluded 20 with suspected pituitary pars intermedia dysfunction (>15 years, ACTH >50 pg/mL). In total, 27% of the ponies (51/188) were hyperinsulinaemic (insulin >20 μIU/mL). The final multivariable model revealed increasing age, supplementary feeding and increased leptin and triglyceride concentrations to be associated with hyperinsulinaemia.
  
  
  CONCLUSIONS
  Hyperinsulinaemia was prevalent and associated with age and evidence of metabolic disturbance, including elevated leptin and triglyceride concentrations, in this population. A significant number of ponies were at risk of hyperinsulinaemia, which has implications for strategies to reduce the risk of laminitis in this population.
authors.affiliation: Philip Leverhulme Equine Hospital, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, United Kingdom.
authors.forename: R A
authors.initials: RA
authors.lastname: Morgan
authors.forename: T W
authors.initials: TW
authors.lastname: McGowan
authors.forename: C M
authors.initials: CM
authors.lastname: McGowan
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D005260:Female; D006734:Horse Diseases / Q000097:blood* / Q000453:epidemiology; D006736:Horses; D006946:Hyperinsulinism / Q000097:blood / Q000453:epidemiology / Q000662:veterinary*; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood; D016015:Logistic Models; D008297:Male; D011793:Queensland / Q000453:epidemiology; D014280:Triglycerides / Q000097:blood
chemical_list: D007328:Insulin; D020738:Leptin; D014280:Triglycerides; D000324:Adrenocorticotropic Hormone
keywords: endocrinopathy; insulin; laminitis; ponies