BMC veterinary research2020; 16(1); 151; doi: 10.1186/s12917-020-02356-w

Weight loss is linearly associated with a reduction of the insulin response to an oral glucose test in Icelandic horses.

Abstract: Insulin dysregulation (ID) goes along with lasting or transient hyperinsulinemia able to trigger equine laminitis, a painful and crippling foot condition. Promoting weight loss through dietary changes and physical activity is currently the main option to prevent this disease. This study aimed at describing the relationship between weight variations and the level of ID as determined by oral glucose tests (OGT). Therefore, the insulin response of 19 Icelandic horses to repeated OGTs was retrospectively analysed considering the variations in their body weight. Results: There was a strong linear relationship between variations in body weight and variations in the total insulin response to OGT as approximated by the area under the curve of insulin (p < 0.001). As indicated by a weighted least squares model, the insulin response decreased by 22% for 5% weight loss on average. However some horses did not respond to weight loss with a reduction of their insulin response to OGT. Additionally, a high correlation between 120 min serum insulin concentration and total insulin response was observed (r = 0.96, p < 0.001). Conclusions: The results corroborate that weight loss is effective against ID and allow for a better quantification of the expected improvement of the insulin response after weight loss. However, it is unclear why some horses did not respond as expected. The high correlation between the 120 min insulin concentration and total insulin response suggests that insulin status can be accurately determined and monitored with only few samples in a practical setting.
Publication Date: 2020-05-24 PubMed ID: 32448298PubMed Central: PMC7245939DOI: 10.1186/s12917-020-02356-wGoogle Scholar: Lookup
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  • Journal Article


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This research indicates a strong linear relationship between weight loss and reduced insulin response in Icelandic horses, as determined through oral glucose tests. However, some horses didn’t respond as expected, indicating more research is needed.

Study Objective and Methodology

  • The aim of the study was to describe the interplay between variations in body weight and insulin dysregulation (ID) levels as determined by oral glucose tests (OGT). Insulin dysregulation is a critical condition as it leads to hyperinsulinemia, a high insulin condition that can trigger equine laminitis, a severe disease causing pain and disability in horses.
  • The research focused on the insulin response of 19 Icelandic horses, analysing their responses to repeated OGTs with consideration to variations in body weight.

Key Findings

  • The research found a strong linear association between body weight variations and alterations in the total insulin response to an OGT, approximated by the area under the curve of insulin. The results indicated a 22% decrease on average in insulin response for a 5% weight loss, according to a weighted least squares model.
  • Nonetheless, some horses didn’t correspond to weight loss with a reduction in their insulin response to OGTs, an irregularity that currently doesn’t have a clear explanation and calls for further investigation.
  • In addition, the study reported a high correlation (r = 0.96; p < 0.001) between the serum insulin concentration at 120 minutes and total insulin response.

Study Implications and Conclusions

  • The findings validate the effectiveness of weight loss against insulin dysregulation (ID) and provides a more precise quantification of the expected enhancement in insulin response after weight loss.
  • The study brings out an important query concerning why some horses didn’t respond as expected to the weight loss in terms of insulin response reduction, this aspect needs further research.
  • The noted high correlation indicates that the insulin status of Icelandic horses can be accurately determined and monitored with only a few samples in a practical setting. This discovery potentially simplifies the assessment and management of equine insulin response in real-world environments.

Cite This Article

Delarocque J, Frers F, Huber K, Feige K, Warnken T. (2020). Weight loss is linearly associated with a reduction of the insulin response to an oral glucose test in Icelandic horses. BMC Vet Res, 16(1), 151.


ISSN: 1746-6148
NlmUniqueID: 101249759
Country: England
Language: English
Volume: 16
Issue: 1
Pages: 151
PII: 151

Researcher Affiliations

Delarocque, Julien
  • Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bu00fcnteweg 9, 30559, Hanover, Germany.
Frers, Florian
  • Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bu00fcnteweg 9, 30559, Hanover, Germany.
Huber, Korinna
  • Institute of Animal Science, Faculty of Agricultural Sciences, University of Hohenheim, Fruwirthstrau00dfe 35, 70593, Stuttgart, Germany.
Feige, Karsten
  • Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bu00fcnteweg 9, 30559, Hanover, Germany.
Warnken, Tobias
  • Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bu00fcnteweg 9, 30559, Hanover, Germany.

MeSH Terms

  • Animals
  • Female
  • Glucose Tolerance Test / veterinary
  • Horse Diseases / blood
  • Horse Diseases / metabolism
  • Horses
  • Insulin / blood
  • Male
  • Metabolic Syndrome / blood
  • Metabolic Syndrome / veterinary
  • Retrospective Studies
  • Weight Loss

Conflict of Interest Statement

The authors declare that they have no competing interests.


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This article has been cited 2 times.
  1. Warnken T, Schaub C, Delarocque J, Frers F, Feige K, Sonntag J, Reiche DB. Palatability, glycemic, and insulinemic responses to various carbohydrate formulations: Alternatives for the diagnosis of insulin dysregulation in horses?. J Vet Intern Med 2023 Jan;37(1):282-291.
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  2. Delarocque J, Frers F, Huber K, Jung K, Feige K, Warnken T. Metabolic impact of weight variations in Icelandic horses.. PeerJ 2021;9:e10764.
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