Veterinary journal (London, England : 1997)2016; 214; 14-20; doi: 10.1016/j.tvjl.2016.02.002

Effect of increased adiposity on insulin sensitivity and adipokine concentrations in different equine breeds adapted to cereal-rich or fat-rich meals.

Abstract: The relationships between diet, obesity and insulin dysregulation in equids require further investigation due to their association with laminitis. This study examined the effect of dietary glycaemic load and increased adiposity on insulin sensitivity and adipokine concentrations in different equine breeds. Equal numbers of Standardbred horses, mixed-breed ponies and Andalusian horses were provided with ad libitum hay plus either cereal-rich (CHO; n = 12), fat-rich (FAT; n = 12) or control (CON; n = 9) meals over 20 weeks. The isocaloric CHO and FAT diets were fed to induce obesity by gradually increasing the supplementary feeds to provide 200% of daily digestible energy requirements by Week 20. The CON group were fed a basal ration only and maintained moderate body condition. At Week 20, the CHO and FAT groups demonstrated significantly increased body condition score, bodyweight, total body fat mass and plasma leptin concentrations compared with the CON group (P <0.001). The CHO group had lower insulin sensitivity (SI; P <0.001) and higher acute insulin response to glucose (P = 0.002) than the CON group. In contrast, the FAT group was no different to the control group. Ponies and Andalusians had lower SI values compared with Standardbreds, regardless of diet group (P = 0.001). Adiponectin concentrations were similar between the FAT and CON groups, but were significantly lower in the CHO group (P = 0.010). The provision of cereal-rich meals appeared to be a more important determinant of insulin sensitivity than the induction of obesity per se. Whether hypoadiponectinaemia is a cause or consequence of insulin dysregulation warrants further investigation.
Publication Date: 2016-02-12 PubMed ID: 27387720DOI: 10.1016/j.tvjl.2016.02.002Google Scholar: Lookup
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This research examined how diet and obesity affect insulin levels and fat-related hormones in different types of horses, such as Standardbreds, mixed-breed ponies, and Andalusian. The study fed the horses high-carbohydrate or high-fat diets for 20 weeks to induce obesity and monitored the changes in their insulin sensitivity and fat-related hormone concentrations. It found that the high-carbohydrate diet notably impacted the horses’ insulin sensitivity and hormone levels, whereas the high-fat diet did not.

Research methodology and diet plan

  • The research involved an equal number of Standardbreds, mixed-breed ponies, and Andalusian horses.
  • The horses were fed unlimited hay and either a diet rich in cereals (CHO), fat (FAT), or a control diet (CON).
  • The high-calorie CHO and FAT diets were used to deliberately induce obesity over the course of 20 weeks. The diets were increased gradually until the horses were consuming 200% of their daily energy requirements by the end of the study.
  • The control group, on the other hand, was given only a basal ration and its body condition was kept moderate.

Findings and observations

  • After the 20 weeks, significant increases were observed in the bodyweight, body condition score, total body fat mass, and plasma leptin concentrations (a hormone that helps regulate energy balance) in both the CHO and FAT groups in comparison to the CON group.
  • The CHO group, however, displayed lower insulin sensitivity (the measure of how responsive cells are to insulin) and a higher acute insulin response than the CON group, whereas the FAT group did not exemplify such variations.
  • Breed-wise, the ponies and Andalusians showed lower insulin sensitivity, irrespective of their diet, compared to the Standardbreds.
  • The adiponectin levels (a hormone involved in glucose regulation and fatty acid breakdown) were not different between the FAT and CON groups but were significantly reduced in the CHO group.


  • The results from this study suggest that diets high in cereals play a more significant role in affecting insulin sensitivity in horses than mere obesity.
  • However, it’s unclear whether the lower adiponectin concentrations observed in the CHO group are a cause or a result of the insulin dysregulation, thus requiring further research in the field.

Cite This Article

Bamford NJ, Potter SJ, Baskerville CL, Harris PA, Bailey SR. (2016). Effect of increased adiposity on insulin sensitivity and adipokine concentrations in different equine breeds adapted to cereal-rich or fat-rich meals. Vet J, 214, 14-20.


ISSN: 1532-2971
NlmUniqueID: 9706281
Country: England
Language: English
Volume: 214
Pages: 14-20
PII: S1090-0233(16)00033-2

Researcher Affiliations

Bamford, N J
  • Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, Australia.
Potter, S J
  • Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, Australia.
Baskerville, C L
  • Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, Australia.
Harris, P A
  • Equine Studies Group, WALTHAM Centre for Pet Nutrition, Melton Mowbray, Leicestershire, UK.
Bailey, S R
  • Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, Australia. Electronic address:

MeSH Terms

  • Adipokines / metabolism
  • Adiposity
  • Animal Feed / analysis
  • Animal Nutritional Physiological Phenomena / drug effects
  • Animals
  • Diet / veterinary
  • Dietary Fats / analysis
  • Dietary Supplements / analysis
  • Edible Grain
  • Female
  • Glycemic Load
  • Horse Diseases / genetics
  • Horse Diseases / physiopathology
  • Horses
  • Insulin Resistance / physiology
  • Male


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  11. Blaue D, Schedlbauer C, Starzonek J, Gittel C, Brehm W, Blu00fcher M, Pfeffer M, Vervuert I. The influence of equine body weight gain on inflammatory cytokine expressions of adipose tissue in response to endotoxin challenge.. Acta Vet Scand 2020 Apr 22;62(1):17.
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  12. Norton E, Schultz N, Geor R, McFarlane D, Mickelson J, McCue M. Genome-Wide Association Analyses of Equine Metabolic Syndrome Phenotypes in Welsh Ponies and Morgan Horses.. Genes (Basel) 2019 Nov 6;10(11).
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  13. Hodge E, Kowalski A, Torcivia C, Lindborg S, Stefanovski D, Hart K, Frank N, van Eps A. Effect of thyrotropin-releasing hormone stimulation testing on the oral sugar test in horses when performed as a combined protocol.. J Vet Intern Med 2019 Sep;33(5):2272-2279.
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  14. Dunkel B, Knowles EJ, Chang YM, Menzies-Gow NJ. Correlation between l-lactate and glucose concentrations and body condition score in healthy horses and ponies.. J Vet Intern Med 2019 Sep;33(5):2267-2271.
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  16. Reynolds A, Keen JA, Fordham T, Morgan RA. Adipose tissue dysfunction in obese horses with equine metabolic syndrome.. Equine Vet J 2019 Nov;51(6):760-766.
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  17. Durham AE, Frank N, McGowan CM, Menzies-Gow NJ, Roelfsema E, Vervuert I, Feige K, Fey K. ECEIM consensus statement on equine metabolic syndrome.. J Vet Intern Med 2019 Mar;33(2):335-349.
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