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Home / Equine Research Bank / BMC Vet Res / Morphometric changes in overweight horses following 10-week ...
BMC veterinary research2025; 21(1); 596; doi: 10.1186/s12917-025-05032-z

Morphometric changes in overweight horses following 10-week weight loss programs.

Abstract: Up to 70% of horses in domestic equine populations are overweight. Promotion of weight loss is an important component of limiting the detrimental co-morbidities associated with excess adipose tissue. The use of a body condition score (BCS) can help equine caregivers track their horse's weight-status. However, this single score doesn't reflect changes in individual adipose depots. The purpose of this study was to characterize morphometric changes (including 8 anatomic BCS measurements that make up the whole-BCS) in horses during 3 different weight-loss programs over 10 weeks. Methods: Thirty-two horses were randomly assigned to one of three weight loss groups [exercise (E; fed to 100% digestible energy (DE) requirements, exercise 5x/week), feed restriction (FR; fed to 85% DE requirements, no exercise), or feed restriction and exercise (FRE; 85% DE, exercise 5x/week)], or a weight-maintained control (C; 100% DE, no exercise)] for 10 weeks. Horses were fed individualized diets formulated to meet their nutritional requirements. Outcome measures were recorded at weeks 1, 5 and 10, and included 11 morphometric measurements [body weight (BW) via weight tape, cresty neck score (CNS), and 8 individual BCSs (neck, shoulder, leg, withers, ribs, back, haunches, and tailhead) and a whole-BCS)]. Data were analyzed using a 2-Way RM ANOVA with respect to treatment group and week. Results: All 4 groups (including controls) had a significant reduction in BW and whole BCS. At week 10 whole BCS was lower in FRE than controls. All groups had a reduction in back, haunches, leg and shoulder; FR, FRE and E horses had reductions in rib BCS; E and FRE horses had reductions in tailhead BCS and CNS. Conclusions: In conclusion, all weight loss strategies produced significant weight loss, but only those strategies which included exercise reduced fat deposits known to be implicated in metabolic dysregulation in obese horses. Future studies should explore the optimum exercise load (duration and intensity) to facilitate loss of fat from these areas.
© 2025. The Author(s).
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Publication Date: 2025-10-10 PubMed ID: 41068901PubMed Central: PMC12512596DOI: 10.1186/s12917-025-05032-zGoogle Scholar: Lookup
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Summary

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Overview

  • This study investigated how different 10-week weight loss programs affect body fat distribution and morphometric measurements in overweight horses.
  • It found that exercise combined with feed restriction more effectively decreases fat in specific areas linked to metabolic problems compared to feed restriction alone or no intervention.

Background and Purpose

  • Up to 70% of domestic horses are overweight, which can lead to serious health issues related to excess fat.
  • Body Condition Score (BCS) is commonly used by caregivers to monitor overall fat but does not reflect changes in specific fat deposits on the body.
  • The study aimed to examine detailed morphometric changes, including eight regional BCS measurements (neck, shoulder, leg, withers, ribs, back, haunches, tailhead), during weight loss across different interventions.

Methods

  • Thirty-two horses were randomly assigned to one of four groups for 10 weeks:
    • Exercise only (E): fed at 100% digestible energy (DE) requirements, exercised 5 times per week.
    • Feed Restriction only (FR): fed at 85% DE requirements, no exercise.
    • Feed Restriction + Exercise (FRE): fed at 85% DE requirements, exercised 5 times per week.
    • Control (C): fed at 100% DE requirements, no exercise.
  • Diets were individually formulated to meet nutritional needs while controlling for energy intake.
  • Measurements were taken at weeks 1, 5, and 10, and included:
    • Body Weight (BW) via weight tape.
    • Cresty Neck Score (CNS) to assess fat accumulation in the neck area.
    • Eight individual BCS regions making up the whole-body BCS (neck, shoulder, leg, withers, ribs, back, haunches, tailhead).
    • Whole-body BCS score.
  • Data analysis used two-way repeated measures ANOVA considering treatment group and time to evaluate effects on morphometric measurements.

Results

  • All groups, including control animals, showed a significant decrease in body weight and whole-body BCS over the study period.
  • At the end of 10 weeks, whole-body BCS was significantly lower in the feed restriction + exercise (FRE) group compared to controls.
  • Specific fat depot changes:
    • All groups exhibited reductions in fat scores around the back, haunches, legs, and shoulders.
    • The FR, FRE, and E groups had reductions in the rib fat BCS, indicating fat loss in the rib area.
    • The E and FRE groups showed reductions in tailhead BCS and cresty neck score (CNS), areas associated with metabolic risk.

Conclusions and Implications

  • Multiple weight loss strategies can result in significant weight loss in overweight horses.
  • However, only those including exercise (E and FRE groups) effectively reduced fat deposits known to contribute to metabolic dysfunction, such as in the crest of the neck and tailhead regions.
  • This suggests exercise is crucial not just for weight loss but for targeting detrimental fat depots linked to health risks.
  • Future research should focus on determining the optimal exercise intensity and duration to maximize fat loss in these critical regions.
  • The study highlights the importance of assessing regional fat changes rather than relying solely on whole-body BCS to monitor health improvements during weight loss programs in horses.

Cite This Article

APA
Garland A, van Doorn DA, van den Boom R, Roelfsema E, Jung L, Boast M, Papadakis K, Margiotta M, Wafelbakker S, Briggs M, McCrae P, Pearson W. (2025). Morphometric changes in overweight horses following 10-week weight loss programs. BMC Vet Res, 21(1), 596. https://doi.org/10.1186/s12917-025-05032-z

Publication

BMC veterinary research
ISSN: 1746-6148
NlmUniqueID: 101249759
Country: England
Language: English
Volume: 21
Issue: 1
Pages: 596
PII: 596

Researcher Affiliations

Garland, Anna
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
van Doorn, David A
  • Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, Utrecht, 3584 CM, The Netherlands.
  • Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, Utrecht, 3584 CM, The Netherlands.
van den Boom, Robin
  • Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, Utrecht, 3584 CM, The Netherlands.
Roelfsema, Ellen
  • Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, Utrecht, 3584 CM, The Netherlands.
Jung, Lola
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Boast, Madeline
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Papadakis, Katerina
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Margiotta, Mary
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Wafelbakker, Samara
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Briggs, Morgan
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
McCrae, Persephone
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Pearson, Wendy
  • Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada. wpearson@uoguelph.ca.

MeSH Terms

  • Animals
  • Horses
  • Horse Diseases / therapy
  • Horse Diseases / diet therapy
  • Horse Diseases / pathology
  • Overweight / veterinary
  • Overweight / therapy
  • Overweight / diet therapy
  • Overweight / pathology
  • Physical Conditioning, Animal
  • Weight Loss / physiology
  • Male
  • Female
  • Body Composition

Grant Funding

  • RGPIN-2020-05823 / Natural Sciences and Engineering Research Council of Canada
  • RGPIN-2020-05823 / Natural Sciences and Engineering Research Council of Canada

Conflict of Interest Statement

Declarations. Ethics approval and consent to participate: All procedures were reviewed and approved by the University of Guelph’s Animal Care Committee (AUP #4436) in accordance with the guidelines of the Canadian Council on Animal Care. Consent for publication: Not Applicable. Competing interests: The authors declare no competing interests.

References

This article includes 38 references
  1. Kosolofski HR, Gow SP, Robinson KA. Prevalence of obesity in the equine population of Saskatoon and surrounding area.. Can Vet J 2017;58:967–70.
    pmc: PMC5556474pubmed: 28878421
  2. Rendle D, McGregor Argo C, Bowen M, Carslake H, German A, Harris P. Equine obesity: current perspectives.. UK-Vet Equine 2018;2:1–19.
    doi: 10.12968/ukve.2018.2.S2.3google scholar: lookup
  3. 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.
    doi: 10.1111/jvim.15423pmc: PMC6430910pubmed: 30724412google scholar: lookup
  4. Kim TH, Choi SE, Ha ES, Jung JG, Han SJ, Kim HJ. IL-6 induction of TLR-4 gene expression via STAT3 has an effect on insulin resistance in human skeletal muscle.. Acta Diabetol 2013;50:189–200.
    doi: 10.1007/s00592-011-0259-zpubmed: 21293887google scholar: lookup
  5. Kaminski DA, Randall TD. Adaptive immunity and adipose tissue biology.. Trends Immunol 2010;31:384–90.
    doi: 10.1016/j.it.2010.08.001pmc: PMC2949534pubmed: 20817556google scholar: lookup
  6. Rodríguez A, Becerril S, Hernández-Pardos AW, Frühbeck G. Adipose tissue depot differences in adipokines and effects on skeletal and cardiac muscle.. Curr Opin Pharmacol 2020;52:1–8.
    doi: 10.1016/j.coph.2020.04.003pubmed: 32387807google scholar: lookup
  7. Peppler WT, Townsend LK, Wright DC. Recent advances in the role of interleukin-6 in health and disease.. Curr Opin Pharmacol 2020;52(1):47–51.
    doi: 10.1016/j.coph.2020.04.010pubmed: 32563931google scholar: lookup
  8. Frank N, Elliott SB, Brandt LE, Keisler DH. Physical characteristics, blood hormone concentrations, and plasma lipid concentrations in obese horses with insulin resistance.. J Am Vet Med Assoc 2006;228:1383–90.
    doi: 10.2460/javma.228.9.1383pubmed: 16649943google scholar: lookup
  9. Cantarelli C, Dau SL, Stefanello S, Azevedo MS, De Bastiani GR, Palma HE. Evaluation of oral sugar test response for detection of equine metabolic syndrome in obese Crioulo horses.. Domest Anim Endocrinol 2018;63:31–7.
    doi: 10.1016/j.domaniend.2017.10.006pubmed: 29287187google scholar: lookup
  10. Harada K, Kanemitsu S, Akioka K, Fujita K, Nishi Y, Taura Y. Epidemiological survey, general blood biochemistry, and histological examination of slaughtered heavy horse breeds with hemorrhage in the adipose tissue in the crest of the neck.. J Equine Sci 2022;33:7–12.
    doi: 10.1294/jes.33.7pmc: PMC9018461pubmed: 35510075google scholar: lookup
  11. Vick MM, Adams AA, Murphy BA, Sessions DR, Horohov DW, Cook RF. Relationships among inflammatory cytokines, obesity, and insulin sensitivity in the horse.. J Anim Sci 2007;85:1144–55.
    doi: 10.2527/jas.2006-673pubmed: 17264235google scholar: lookup
  12. Treiber KH, Kronfeld DS, Hess TM, Byrd BM, Splan RK, Staniar WB. Evaluation of genetic and metabolic predispositions and nutritional risk factors for pasture-associated laminitis in ponies.. J Am Vet Med Assoc 2006;228:1538–45.
    doi: 10.2460/javma.228.10.1538pubmed: 16677122google scholar: lookup
  13. Johnson PJ, Wiedmeyer CE, LaCarrubba A, Seshu Ganjam VK, Messer NT. Laminitis and the equine metabolic syndrome.. Vet Clin North Am Equine Pract 2010;26:239–55.
    doi: 10.1016/j.cveq.2010.04.004pubmed: 20699172google scholar: lookup
  14. Moore JL, Siciliano PD, Pratt-Phillips SE. Effects of diet versus exercise on morphometric measurements, blood hormone concentrations, and oral sugar test response in obese horses.. J Equine Vet Sci 2019;78:38–45.
    doi: 10.1016/j.jevs.2019.03.214pubmed: 31203982google scholar: lookup
  15. Roelfsema E, van Doorn D. Influence of exercise and/or dietary restriction on weight loss in Welsh ponies.. In: European Equine Health & Nutrition Congress 8th edition. 2017. p. 48.
  16. 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;33:280–6.
    doi: 10.1111/jvim.15374pmc: PMC6335535pubmed: 30520164google scholar: lookup
  17. Gordon ME, Jerina ML, Raub RH, Davison KA, Young JK, Williamson KK. The effects of dietary manipulation and exercise on weight loss and related indices of health in horses.. Comp Exerc Physiol 2009;6:33–42.
    doi: 10.1017/S1478061509356169google scholar: lookup
  18. Argo CM, Curtis GC, Grove-White D, Dugdale AHA, Barfoot CF, Harris PA. Weight loss resistance: a further consideration for the nutritional management of obese equidae.. Vet J 2012;194:179–88.
    doi: 10.1016/j.tvjl.2012.09.020pubmed: 23117030google scholar: lookup
  19. Garland A. In vitro and in vivo investigations of inflammatory and morphometric consequences in overweight equines.. [PhD thesis]. Guelph (ON): University of Guelph. 2024.
  20. National Research Council. Nutrient requirements of horses. 6th Edition.. National Academies Press. 2007.
  21. Ebert M, Moore-Colyer MJS. The energy requirements of performance horses in training.. Transl Anim Sci 2020;4:txaa032.
    doi: 10.1093/tas/txaa032pmc: PMC7201169pubmed: 32705030google scholar: lookup
  22. Pagan JD, Hintz HF. Equine energetics. II. Energy expenditure in horses during submaximal exercise.. J Anim Sci 1986;63:822–30.
    doi: 10.2527/jas1986.633822xpubmed: 3759710google scholar: lookup
  23. Carter RA, Geor RJ, Staniar W, Cubitt TA, Harris PA. Apparent adiposity assessed by standardised scoring systems and morphometric measurements in horses and ponies.. Vet J 2009;179:204–10.
    doi: 10.1016/j.tvjl.2008.02.029pubmed: 18440844google scholar: lookup
  24. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body fat percentage in mares.. Equine Vet J 1983;15:371–2.
    doi: 10.1111/j.2042-3306.1983.tb01826.xpubmed: 6641685google scholar: lookup
  25. Carter RA, McCutcheon LJ, Valle E, Meilahn EN, Geor RJ. Effects of exercise training on adiposity, insulin sensitivity, and plasma hormone and lipid concentrations in overweight or obese, insulin-resistant horses.. Am J Vet Res 2010;71:314–21.
    doi: 10.2460/ajvr.71.3.314pubmed: 20187833google scholar: lookup
  26. Dugdale AH, Curtis GC, Harris PA, Argo CM. Assessment of body fat in the pony: part I. Relationships between the anatomical distribution of adipose tissue, body composition and body condition.. Equine Vet J 2011;43:552–61.
    doi: 10.1111/j.2042-3306.2010.00330.xpubmed: 21496091google scholar: lookup
  27. Martinson K, Wilson J, Cleary K, Lazarus W, Thomas W, Hathaway M. Round-bale feeder design affects hay waste and economics during horse feeding.. J Anim Sci 2012;90:1047–55.
    doi: 10.2527/jas.2011-4087pubmed: 21984721google scholar: lookup
  28. Bruynsteen L, Erkens T, Peelman LJ, Ducatelle R, Janssens GP, Harris PA. Expression of inflammation-related genes is associated with adipose tissue location in horses.. BMC Vet Res 2013;9:240.
    doi: 10.1186/1746-6148-9-240pmc: PMC4220830pubmed: 24295090google scholar: lookup
  29. Blaue D, Schedlbauer C, Starzonek J, Gittel C, Brehm W, Blüher M. The influence of equine body weight gain on inflammatory cytokine expressions of adipose tissue in response to endotoxin challenge.. Acta Vet Scand 2020;62:17.
    doi: 10.1186/s13028-020-00515-5pmc: PMC7178607pubmed: 32321549google scholar: lookup
  30. Ferjak EN, Cavinder CA, Sukumaran AT, Burnett DD, Lemley CO, Dinh TTN. Fatty acid composition of mesenteric, cardiac, abdominal, intermuscular, and subcutaneous adipose tissues from horses of three body condition scores.. Livest Sci 2019;223:116–23.
    doi: 10.1016/j.livsci.2019.02.010google scholar: lookup
  31. Royal Horse. How to estimate the body condition of your horse? https://www.royal-horse.com/advice/estimate-body-state-horse/#:~:text=Ribs:%20This%20area%20is%20of,making%20the%20ribs%20more%20obvious. Accessed July 23, 2025.
  32. Donnelly JE, Smith B, Jacobsen DJ, Kirk E, DuBose K, Hyder M. The role of exercise for weight loss and maintenance. Best Pract Res Clin Gastroenterol 2004;18:1009–29.
    doi: 10.1016/S1521-6918(04)00083-6pubmed: 15561636google scholar: lookup
  33. Curioni CC, Lourenço PM. Long-term weight loss after diet and exercise: a systematic review. Int J Obes 2005;29:1168–74.
    doi: 10.1038/sj.ijo.0803015pubmed: 15925949google scholar: lookup
  34. Vick MM, Sessions DR, Murphy BA, Kennedy EL, Reedy SE, Fitzgerald BP. Obesity is associated with altered metabolic and reproductive activity in the mare: effects of Metformin on insulin sensitivity and reproductive cyclicity. Reprod Fertil Dev 2006;18:609.
    doi: 10.1071/RD06016pubmed: 16930507google scholar: lookup
  35. Suagee JK, Corl BA, Geor RJ. A potential role for pro-inflammatory cytokines in the development of insulin resistance in horses. Animals 2012;2:243–60.
    doi: 10.3390/ani2020243pmc: PMC4494330pubmed: 26486919google scholar: lookup
  36. Selim S, Elo K, Jaakkola S, Karikoski N, Boston R, Reilas T. Relationships among body condition, insulin resistance and subcutaneous adipose tissue gene expression during the grazing season in mares. PLoS ONE 2015;10:e0125968.
    doi: 10.1371/journal.pone.0125968pmc: PMC4418745pubmed: 25938677google scholar: lookup
  37. Pratt-Phillips S. Effect of exercise conditioning on countering the effects of obesity and insulin resistance in horses-a review. Animals 2024;14:727.
    doi: 10.3390/ani14050727pmc: PMC10931081pubmed: 38473112google scholar: lookup
  38. Pearson W, Wood K, Stanley S, MacNicol J. Exploring relationships between body condition score, body fat, activity level and inflammatory biomarkers. J Anim Physiol Anim Nutr (Berl) 2018;102:1062–8.
    doi: 10.1111/jpn.12893pubmed: 29707811google scholar: lookup

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