FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Equine veterinary journal2023; 56(2); 253-263; doi: 10.1111/evj.13983

Factors associated with insulin responses to oral sugars in a mixed-breed cohort of ponies.

Abstract: Serum insulin concentration at 60 min (InsulinT60) during an oral sugar test (OST) indicates future laminitis risk and insulin dysregulation (ID). Associations between InsulinT60 and physical and owner-reported variables may help clinicians select individuals for ID testing. Associations between InsulinT60 and other metabolic markers may help elucidate ID pathophysiology. Objective: To describe associations between (A) season, physically-apparent and owner-reported factors and binary InsulinT60 interpretation (initial models) and (B) variables included in the initial models, other metabolic markers and continuous InsulinT60 (full models). Methods: Prospective longitudinal. Methods: Non-laminitic ponies were examined and OSTs (0.3 mL/kg Karo syrup) performed every 6 months (autumn and spring) for ≤4 years. Factors associated with InsulinT60 were determined using mixed-effects models with physical, owner-reported, season and serum/plasma markers as fixed effects and pony and premises identifiers as random effects. Autumn and spring data were analysed separately for full models. Results: One thousand seven hundred and sixty-three OSTs from 367 ponies were included. High-risk InsulinT60 (>153 μIU/mL) was independently associated with (odds ratio, 95% confidence interval [CI]): age (1.36, 1.16-1.60), body condition score (BCS) (2.38, 1.21-4.69), and bulging supraorbital fatpads (7.25, 2.1-24.98). However, the initial models provided little explanatory power (Nakagawa R2  = 0.1-0.27). LoginsulinT60 was independently associated with (effect estimate, 95% CI): age (0.02, 0.01-0.04), Welsh/Welsh X breed (0.22, 0.05, 0.39), sex (gelding = -0.2, -0.34 to 0.06), BCS (0.16, 0.08-0.23), plasma adiponectin (-0.02, -0.02 to 0.01) and basal insulin (0.01, 0.01-0.01) in spring, and: age (0.03, 0.02-0.04), BCS (0.17, 0.08-0.26), bulging supraorbital fatpads (0.37, 0.2-0.54), turnout score (0.05, 0.02-0.09), plasma adiponectin (-0.01, -0.02 to 0.01), ACTH (per 10 pg/mL) (0.01, 0.00-0.01), triglycerides (0.28, 0.07-0.49) and InsulinT0 (0.01, 0.01-0.01) in autumn. Conclusions: Only non-laminitic ponies in one region were included. Conclusions: Owner-reported and physically-apparent data were limited InsulinT60 predictors. InsulinT60 is a complex trait, independently associated with numerous variables, some with seasonal interactions.
© 2023 Mars Horsecare and The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
Get Full Text
Publication Date: 2023-08-22 PubMed ID: 37606314DOI: 10.1111/evj.13983Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The study explores the factors linked to insulin responses to oral sugars in ponies, with a focus on serum insulin concentration at 60 minutes. Identifying these factors aids clinicians in selecting individuals for testing of insulin dysregulation and understanding its pathophysiology.

Research Design and Methods

  • The researchers carried out a prospective longitudinal study on non-laminitic ponies for as long as four years.
  • These ponies were examined and subjected to oral sugar tests (OSTs) every six months – during the autumn and spring seasons.
  • Research variables including physical characteristics, owner-reported data, seasonality, and serum/plasma markers were used as fixed effects in mixed-effects models.
  • Pony and premises identifiers were used as random effects.

Findings and Results

  • A total of 1,763 OSTs from 367 ponies were analysed.
  • Risk-insulin concentration (InsulinT60 >153 μIU/mL) was associated independently with the ponies’ age, their body condition score (BCS), and the presence of bulging supraorbital fat pads.
  • However, the initial models provided minimal explanatory power as indicated by the Nakagawa R ranging from 0.1-0.27.
  • In spring, the logarithm of insulin concentration at 60 min (LoginsulinT60) was independently associated with age, Welsh/Welsh X breed, sex, BCS, plasma adiponectin, and basal insulin.
  • In autumn, LoginsulinT60 was independently associated with age, BCS, bulging supraorbital fatpads, turnout score, plasma adiponectin, ACTH (adrenocorticotropic hormone), triglycerides, and InsulinT0 (initial insulin concentration).

Conclusions

  • The research only included non-laminitic ponies in one region, limiting the generalisation of the results.
  • Data provided by the ponies’ owners and physically apparent characteristics were found to be limited predictors of the ponies’ insulin responses to oral sugars.
  • InsulinT60 was determined to be a complex trait associated independently with numerous variables, some of which displayed seasonal interactions.

Cite This Article

APA
Knowles EJ, Harris PA, Elliott J, Chang YM, Menzies-Gow NJ. (2023). Factors associated with insulin responses to oral sugars in a mixed-breed cohort of ponies. Equine Vet J, 56(2), 253-263. https://doi.org/10.1111/evj.13983

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 56
Issue: 2
Pages: 253-263

Researcher Affiliations

Knowles, Edward J
  • Department of Clinical Science and Services, The Royal Veterinary College, Hatfield, UK.
  • Bell Equine Veterinary Clinic, Kent, UK.
Harris, Patricia A
  • Waltham Petcare Science Institute, Leicestershire, UK.
Elliott, Jonathan
  • Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK.
Chang, Yu-Mei
  • Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK.
Menzies-Gow, Nicola J
  • Department of Clinical Science and Services, The Royal Veterinary College, Hatfield, UK.

MeSH Terms

  • Humans
  • Horses
  • Male
  • Animals
  • Insulin / metabolism
  • Sugars
  • Adiponectin
  • Prospective Studies
  • Blood Glucose / metabolism
  • Horse Diseases

Grant Funding

  • Royal Veterinary College from the Mellon Trust
  • Mars Petcare

References

This article includes 24 references
  1. Durham AE, Frank N, McGowan CM, Menzies-Gow NJ, Roelfsema E, Vervuert I. ECEIM consensus statement on equine metabolic syndrome.. J Vet Intern Med 2019;33:335-349.
  2. Knowles EJ, Elliott J, Harris PA, Chang Y, Menzies-Gow NJ. Predictors of laminitis development in a cohort of nonlaminitic ponies.. Equine Vet J 2022;55(1):12-23.
  3. Carslake HB, Pinchbeck GL, McGowan CM. Equine metabolic syndrome in UK native ponies and cobs is highly prevalent with modifiable risk factors.. Equine Vet J 2021;53:923-934.
  4. McGowan TW, Pinchbeck GP, McGowan CM. Prevalence, risk factors and clinical signs predictive for equine pituitary pars intermedia dysfunction in aged horses.. Equine Vet J 2013;45:74-79.
  5. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body fat percentage in mares.. Equine Vet J 1983;15:371-372.
  6. Carter RA, Geor RJ, Burton Staniar W, Cubitt TA, Harris PA. Apparent adiposity assessed by standardised scoring systems and morphometric measurements in horses and ponies.. Vet J 2009;179:204-210.
  7. Beech J, Boston RC, McFarlane D, Lindborg S. Evaluation of plasma ACTH, alpha melanocyte stimulating hormone, and insulin concentrations during various photoperiods in clinically normal horses and ponies and those with pituitary pars intermedia dysfunction.. J Am Vet Med Assoc 2009;235:715-722.
  8. Knowles EJ, Shaw S, Harris PA, Elliott J. Plasma adrenocorticotropic hormone (ACTH) concentrations in ponies measured by two different assays suggests seasonal cross-reactivity or interference.. Equine Vet J 2018;50:672-677.
  9. The Equine Endocrinology Group. Recommendations for the diagnosis and treatment of pituitary pars intermedia dysfunction (PPID). 2019.
  10. Johnson DR, Creech JC. Ordinal measures in multiple indicator models: a simulation study of categorization error.. Am Sociol Rev 1983;48:398-407.
  11. Nakagawa S, Schielzeth H. A general and simple method for obtaining R2 from generalized linear mixed-effects models.. Methods Ecol Evol 2013;2:133-142.
  12. Dugdale AHA, Grove-White D, Curtis GC, Harris PA, McG AC. Body condition scoring as a predictor of body fat in horses and ponies.. Vet J 2012;194:173-178.
  13. Bamford NJ, Potter SJ, Harris PA, Bailey SR. Effect of increased adiposity on insulin sensitivity and adipokine concentrations in horses and ponies fed a high fat diet, with or without a once daily high glycaemic meal.. Equine Vet J 2016;48:368-373.
  14. Bamford NJ, Potter SJ, Baskerville CL, Harris PA, Bailey SR. Effect of increased adiposity on insulin sensitivity and adipokine concentrations in different equine breeds adapted to cereal-rich or fat-rich meals.. Vet J 2016;214:14-20.
  15. Box JR, McGowan CM, Raekallio MR, Mykkänen AK, Carslake H, Karikoski NP. Insulin dysregulation in a population of Finnhorses and associated phenotypic markers of obesity.. J Vet Intern Med 2020;34:1599-1605.
  16. Morgan RA, McGowan TW, McGowan CM. Prevalence and risk factors for hyperinsulinaemia in ponies in Queensland, Australia.. Aust Vet J 2014;92:101-106.
  17. Norton EM, Schultz NE, Rendahl AK, Mcfarlane D, Geor RJ, Mickelson JR. Heritability of metabolic traits associated with equine metabolic syndrome in Welsh ponies and Morgan horses.. Equine Vet J 2019;51:475-480.
  18. Morgan RA, Keen JA, McGowan CM. Treatment of equine metabolic syndrome: a clinical case series.. Equine Vet J 2016;48:422-426.
  19. Bamford NJ, Potter SJ, Baskerville CL, Harris PA, Bailey SR. Influence of dietary restriction and low-intensity exercise on weight loss and insulin sensitivity in obese equids.. J Vet Intern Med 2019;33:280-286.
  20. Bailey SR, Habershon-Butcher JL, Ransom KJ, Elliott J, Menzies-Gow NJ. Hypertension and insulin resistance in a mixed-breed population of ponies predisposed to laminitis.. Am J Vet Res 2008;69:122-129.
  21. Ungru J, Blüher M, Coenen M, Raila J, Boston R, Vervuert I. Effects of body weight reduction on blood adipokines and subcutaneous adipose tissue adipokine mRNA expression profiles in obese ponies.. Vet Rec 2012;171:528.
  22. Altman DG, Royston P. The cost of dichotomising continuous variables.. Br Med J 2006;332:1080.
  23. Tatum RC, McGowan CM, Ireland JL. Evaluation of the sensitivity and specificity of basal plasma adrenocorticotrophic hormone concentration for diagnosing pituitary pars intermedia dysfunction in horses: a systematic review.. Vet J 2021;275:105695.
  24. Knowles EJ, Elliott J, Harris PA, Menzies-Gow NJ. Laminitis risk categories for serum insulin concentrations differ between two analysers.. Equine Vet J 2022;54(S57):24-25.

Citations

This article has been cited 3 times.
  1. Espinosa-López EM, Ortiz-Guisado B, Diez de Castro E, Durham A, Aguilera-Tejero E, Gómez-Baena G. Quantitative proteomics unveils potential plasma biomarkers and provides insights into the pathophysiological mechanisms underlying equine metabolic syndrome. BMC Vet Res 2025 Jul 2;21(1):425.
    doi: 10.1186/s12917-025-04879-6pubmed: 40604814google scholar: lookup
  2. Fouché N, Doras C, Schüpbach-Regula G, Scherer A, Freudenschuss B, Gerber V. Association Between Adrenocorticotropic Hormone Concentration and Clinical Signs of Pituitary Pars Intermedia Dysfunction in Swiss and Austrian Equids. J Vet Intern Med 2025 Mar-Apr;39(2):e70008.
    doi: 10.1111/jvim.70008pubmed: 40095750google scholar: lookup
  3. Menzies-Gow NJ, Knowles EJ. Sodium-glucose transport protein 2 inhibitor use in the management of insulin dysregulation in ponies and horses. J Vet Pharmacol Ther 2025 Jan;48 Suppl 1(Suppl 1):31-40.
    doi: 10.1111/jvp.13470pubmed: 38984777google scholar: lookup
Subscribe to our newsletter
Join 99,850 horse owners like you who receive our email updates on horse health and nutrition.