Physiological reports2021; 9(11); e14824; doi: 10.14814/phy2.14824

Increased body fat content in horses alters metabolic and physiological exercise response, decreases performance, and increases locomotion asymmetry.

Abstract: This study examined the effect of altered body weight (BW) and body fat content on exercise performance and recovery. Nine horses were divided into two groups, and changes in BW and fat content were induced by feeding a high (HA) or restricted (RA) energy allowance for 36 days in a cross-over design. In the last week of each treatment, BW and body condition score (BCS) were recorded, body fat percentage was estimated using ultrasound, and a standardized incremental treadmill exercise test (SET) and competition-like field test were performed (scored by judges blinded to treatments). Blood samples were collected, and heart rate (HR), rectal temperature (RT), and respiratory rate (RR) were also recorded. Objective locomotion analyses were performed before and after the field test. Body weight, body fat percentage, and BCS were higher (5-8%) in HA than in RA horses (p < 0.05). In SET, HA horses showed higher HR, plasma lactate concentration, RR, and RT than RA horses (p < 0.05), and lower V , hematocrit (Hct), plasma glucose, and plasma NEFA concentrations (p < 0.05). Hct was also lower in HA horses in the field test, while RA horses showed higher scores (p < 0.05). After both tests, resting plasma lactate concentrations were reached faster in RA than in HA horses (p < 0.05). Objective locomotion asymmetry was higher in HA than in RA (p < 0.05). These results clearly show that increased BW and body fat content in horses lower physiological fitness in terms of V , plasma lactate removal, Hct levels, plasma glucose availability and reduce true performance evaluated by blinded judges.
Publication Date: 2021-06-11 PubMed ID: 34110691PubMed Central: PMC8191395DOI: 10.14814/phy2.14824Google 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.
  • 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 research investigates the effects of varying body weight and body fat content on horse performance and recovery. It demonstrates that higher body weight and fat content degrade physiological response during exercise and impair recovery.

Study Design and Methodology

  • The study used a controlled experiment involving nine horses. The horses were split into two groups and given different diets to induce changes in body weight and fat content with a high energy allowance (HA) and a restricted allowance (RA).
  • Over a period of 36 days, the horses underwent a series of tests and measurements. Their body weight, body condition score, and body fat percentage were recorded in the last week of each diet. The body fat percentage was estimated using ultrasound technology.
  • Exercise mechanics were evaluated using a standardized incremental treadmill exercise test (SET) and a field task similar to an actual competition scenario. Judges, unaware of which horses were in each group, assessed the horses’ performance in these tests.
  • Physiological markers were also monitored during these tests. These included heart rate, plasma lactate concentration, respiratory rate, rectal temperature, hematocrit (proportion of red blood cells in the blood), plasma glucose, and plasma Non-Esterified Fatty Acids (NEFA) concentrations.
  • Lameness or locomotion asymmetry was tested before and after the field activity.

Key Findings

  • Horses in the HA diet group had higher body weight, fat percentage, and body condition scores by 5-8% compared to the RA diet horses.
  • During the SET, the HA horses had higher heart rates, plasma lactate concentrations, respiratory rates, and rectal temperatures compared to the RA group. Conversely, the HA horses showed lower hematocrit, plasma glucose, and plasma NEFA concentrations.
  • HA horses also showed lower hematocrit in the field test, and the RA horses received higher scores for performance.
  • After both tests, the RA horses achieved resting plasma lactate concentrations faster (i.e., they recovered more quickly) than the HA horses.
  • Lameness or locomotion asymmetry was higher in the HA group than the RA group.

Conclusion

The results clearly suggest that an increase in body weight and fat content negatively impacts the physiological performance capacity of horses. It leads to decreased endurance (indicated by lower V), slower lactate metabolism, lower hematocrit levels, reduced glucose availability, and diminished overall performance, evaluated on the basis of objective measures and human assessments. The study’s findings are significant for improving understanding of equine health and performance, and for informing strategies for feeding, training, and managing horses to optimize their performance and welfare.

Cite This Article

APA
Jansson A, Gunnarsson Vu00de, Ringmark S, Ragnarsson S, Su00f6derroos D, u00c1sgeirsson E, Ju00f3hannsdu00f3ttir TR, Liedberg C, Stefu00e1nsdu00f3ttir GJ. (2021). Increased body fat content in horses alters metabolic and physiological exercise response, decreases performance, and increases locomotion asymmetry. Physiol Rep, 9(11), e14824. https://doi.org/10.14814/phy2.14824

Publication

ISSN: 2051-817X
NlmUniqueID: 101607800
Country: United States
Language: English
Volume: 9
Issue: 11
Pages: e14824
PII: e14824

Researcher Affiliations

Jansson, Anna
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Gunnarsson, Vikingur u00de
  • Department of Equine Science, Hu00f3lar University, Sauu00f0u00e1rkru00f3kur, Iceland.
Ringmark, Sara
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Ragnarsson, Sveinn
  • Department of Equine Science, Hu00f3lar University, Sauu00f0u00e1rkru00f3kur, Iceland.
Su00f6derroos, Denise
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
  • Department of Equine Science, Hu00f3lar University, Sauu00f0u00e1rkru00f3kur, Iceland.
u00c1sgeirsson, Einar
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Ju00f3hannsdu00f3ttir, Tanja R
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Liedberg, Charlotta
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Stefu00e1nsdu00f3ttir, Guu00f0ru00fan J
  • Department of Equine Science, Hu00f3lar University, Sauu00f0u00e1rkru00f3kur, Iceland.

MeSH Terms

  • Adipose Tissue / physiology
  • Animals
  • Body Temperature / physiology
  • Heart Rate / physiology
  • Horses / metabolism
  • Horses / physiology
  • Locomotion / physiology
  • Male
  • Physical Conditioning, Animal / physiology
  • Respiratory Rate / physiology

Grant Funding

  • The Stock Production Fund of the Icelandic Horse Breed

References

This article includes 48 references
  1. Adams AA, Katepalli MP, Kohler K, Reedy SE, Stilz JP, Vick MM, Fitzgerald BP, Lawrence LM, Horohov DW. Effect of body condition, body weight and adiposity on inflammatory cytokine responses in old horses.. Vet Immunol Immunopathol 2009 Feb 15;127(3-4):286-94.
    doi: 10.1016/j.vetimm.2008.10.323pubmed: 19097648google scholar: lookup
  2. Berenbaum F, Eymard F, Houard X. Osteoarthritis, inflammation and obesity.. Curr Opin Rheumatol 2013 Jan;25(1):114-8.
    doi: 10.1097/BOR.0b013e32835a9414pubmed: 23090672google scholar: lookup
  3. Bitschnau C, Wiestner T, Trachsel DS, Auer JA, Weishaupt MA. Performance parameters and post exercise heart rate recovery in Warmblood sports horses of different performance levels.. Equine Vet J Suppl 2010 Nov;(38):17-22.
  4. Blaue D, Schedlbauer C, Starzonek J, Gittel C, Brehm W, Einspanier A, Vervuert I. Effects of body weight gain on insulin and lipid metabolism in equines.. Domest Anim Endocrinol 2019 Jul;68:111-118.
  5. Browning, R. C. (2012). Locomotion mechanics in obese adults and children. Current Obesity Reports, 1, 152u2013159. 10.1007/s13679-012-0021-z.
    doi: 10.1007/s13679-012-0021-zgoogle scholar: lookup
  6. Buchan L, St Aubin CR, Fisher AL, Hellings A, Castro M, Al-Nakkash L, Broderick TL, Plochocki JH. High-fat, high-sugar diet induces splenomegaly that is ameliorated with exercise and genistein treatment.. BMC Res Notes 2018 Oct 22;11(1):752.
    doi: 10.1186/s13104-018-3862-zpmc: PMC6198361pubmed: 30348225google scholar: lookup
  7. 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 Feb;179(2):204-10.
    doi: 10.1016/j.tvjl.2008.02.029pubmed: 18440844google scholar: lookup
  8. Connysson M, Essu00e9n-Gustavsson B, Lindberg JE, Jansson A. Effects of feed deprivation on Standardbred horses fed a forage-only diet and a 50:50 forage-oats diet.. Equine Vet J Suppl 2010 Nov;(38):335-40.
  9. Danielsen, K. , Lawrence, L. M. , Siciliano, P. , Powell, D. , & Thompson, K. (1995). Effect of diet on weight and plasma variables in endurance exercised horses. Equine Veterinary Journal, 18, 372u2013377. 10.1111/j.2042-3306.1995.tb04955.x.
  10. Farris JW, Hinchcliff KW, McKeever KH, Lamb DR, Thompson DL. Effect of tryptophan and of glucose on exercise capacity of horses.. J Appl Physiol (1985) 1998 Sep;85(3):807-16.
    doi: 10.1152/jappl.1998.85.3.807pubmed: 9729551google scholar: lookup
  11. FEIF (2015). Approved information about Breeding Shows. https://www.feif.org/files/documents/FiZObooklet_2015.pdf.
  12. Fonseca RG, Kenny DA, Hill EW, Katz LM. The relationship between body composition, training and race performance in a group of Thoroughbred flat racehorses.. Equine Vet J 2013 Sep;45(5):552-7.
    doi: 10.1111/evj.12024pubmed: 23294231google scholar: lookup
  13. Garlinghouse SE, Burrill MJ. Relationship of body condition score to completion rate during 160 km endurance races.. Equine Vet J Suppl 1999 Jul;(30):591-5.
  14. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body fat percentage in mares.. Equine Vet J 1983 Oct;15(4):371-2.
  15. Hoffman RM, Boston RC, Stefanovski D, Kronfeld DS, Harris PA. Obesity and diet affect glucose dynamics and insulin sensitivity in Thoroughbred geldings.. J Anim Sci 2003 Sep;81(9):2333-42.
    doi: 10.2527/2003.8192333xpubmed: 12968709google scholar: lookup
  16. Jansson A, Lindberg JE. A forage-only diet alters the metabolic response of horses in training.. Animal 2012 Dec;6(12):1939-46.
    doi: 10.1017/S1751731112000948pubmed: 22717208google scholar: lookup
  17. Jansson, A. , Lindberg, J. , Rundgren, M. , Mu00fcller, C. , Connysson, M. , Kjellberg, L. , & Lundberg, M. 2011. Utfodringsrekommendationer fu00f6r hu00e4st. Report 289. Department of animal nutrition and management, Swedish University of Agricultural Sciences. https://www.slu.se/institutioner/husdjurensu2010utfodringu2010vard/Verktyg/utfodringsrekommendationeru2010foru2010hast/
  18. Jansson A, Stu00e9fansdu00f3ttir GJ, Ragnarsson S. Plasma insulin concentration increases linearly with body condition in Icelandic horses.. Acta Vet Scand 2016 Nov 9;58(1):76.
    doi: 10.1186/s13028-016-0258-8pmc: PMC5103404pubmed: 27829433google scholar: lookup
  19. Jensen RB, Danielsen SH, Tauson AH. Body condition score, morphometric measurements and estimation of body weight in mature Icelandic horses in Denmark.. Acta Vet Scand 2016 Oct 20;58(Suppl 1):59.
    doi: 10.1186/s13028-016-0240-5pmc: PMC5073991pubmed: 27766968google scholar: lookup
  20. Ju00f6nsson L, Egenvall A, Roepstorff L, Nu00e4sholm A, Dalin G, Philipsson J. Associations of health status and conformation with longevity and lifetime competition performance in young Swedish Warmblood riding horses: 8,238 cases (1983-2005).. J Am Vet Med Assoc 2014 Jun 15;244(12):1449-61.
    doi: 10.2460/javma.244.12.1449pubmed: 24871069google scholar: lookup
  21. Kearns CF, McKeever KH, John-Alder H, Abe T, Brechue WF. Relationship between body composition, blood volume and maximal oxygen uptake.. Equine Vet J Suppl 2002 Sep;(34):485-90.
  22. Kearns CF, McKeever KH, Kumagai K, Abe T. Fat-free mass is related to one-mile race performance in elite standardbred horses.. Vet J 2002 May;163(3):260-6.
    doi: 10.1053/tvjl.2001.0656pubmed: 12090768google scholar: lookup
  23. King, C. M. , Evans, D. L. , & Rose, R. J. (1995). Acclimation to treadmill exercise. Equine Veterinary Journal Supplement, 18, 453u2013456. 10.1111/j.2042-3306.1995.tb04972.x.
  24. Klein, D. J. , Anthony, T. G. , & McKeever, K. H. (2020). Changes in maximal aerobic capacity, body composition, and running capacity with prolonged training and detraining in Standardbred horses. Comparative Exercise Physiology, 16, 187u2013195. 10.3920/CEP190046.
    doi: 10.3920/CEP190046google scholar: lookup
  25. Lawrence, L. , Jackson, S. , Kline, K. , Moser, L. , Powell, D. , & Biel, M. (1992). Observations of body weight and condition of horses in a 150u2010mile endurance ride. Journal of Equine Veterinary Science, 12, 320u2013324. 10.1016/S0737-0806(06)81345-6.
  26. Leleu C, Cotrel C. Body composition in young standardbreds in training: relationships to body condition score, physiological and locomotor variables during exercise.. Equine Vet J Suppl 2006 Aug;(36):98-101.
  27. Leleu C, Cotrel C, Courouce-Malblanc A. Relationships between physiological variables and race performance in French standardbred trotters.. Vet Rec 2005 Mar 12;156(11):339-42.
    doi: 10.1136/vr.156.11.339pubmed: 15789646google scholar: lookup
  28. Lewis DA, Kamon E, Hodgson JL. Physiological differences between genders. Implications for sports conditioning.. Sports Med 1986 Sep-Oct;3(5):357-69.
  29. Lindgren, E. 1979. . The nutritional value of roughages determined in vivo and by laboratory methods. Report 45:63, Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, .
  30. Mack SJ, Kirkby K, Malalana F, McGowan CM. Elevations in serum muscle enzyme activities in racehorses due to unaccustomed exercise and training.. Vet Rec 2014 Feb 8;174(6):145.
    doi: 10.1136/vr.101669pubmed: 24415762google scholar: lookup
  31. Marshall WG, Hazewinkel HA, Mullen D, De Meyer G, Baert K, Carmichael S. The effect of weight loss on lameness in obese dogs with osteoarthritis.. Vet Res Commun 2010 Mar;34(3):241-53.
    doi: 10.1007/s11259-010-9348-7pmc: PMC2855019pubmed: 20237844google scholar: lookup
  32. McCracken MJ, Kramer J, Keegan KG, Lopes M, Wilson DA, Reed SK, LaCarrubba A, Rasch M. Comparison of an inertial sensor system of lameness quantification with subjective lameness evaluation.. Equine Vet J 2012 Nov;44(6):652-6.
  33. McGoey BV, Deitel M, Saplys RJ, Kliman ME. Effect of weight loss on musculoskeletal pain in the morbidly obese.. J Bone Joint Surg Br 1990 Mar;72(2):322-3.
    doi: 10.1302/0301-620X.72B2.2138158pubmed: 2138158google scholar: lookup
  34. NRC (2007). Nutrient Requirements of Horses (6th ed.). National Academic Press.
  35. Nyman S, Jansson A, Lindholm A, Dahlborn K. Water intake and fluid shifts in horses: effects of hydration status during two exercise tests.. Equine Vet J 2002 Mar;34(2):133-42.
    doi: 10.2746/042516402776767213pubmed: 11902756google scholar: lookup
  36. Palmgrenu2010Karlsson, C. , Lindberg, J. E. , & Rundgren, M. (2000). Associative effects on total tract digestibility in horses fed different ratios of grass hay and whole oats. Livestock Production Science, 65, 143u2013153. 10.1016/S0301-6226(99)00178-5.
  37. Poortvliet, E. , Hurtig Wennlu00f6f, A. , & Yngve, A. (2001). Kroppens sammansu00e4ttning av betydelse fu00f6r prestationen. Svensk Idrottsforskning, 2, 18u201323. https://centrumforidrottsforskning.se/wpu2010content/uploads/2014/04/Kroppensu2010sammansattningu2010prestation.pdf.
  38. Ragnarsson S, Jansson A. Comparison of grass haylage digestibility and metabolic plasma profile in Icelandic and Standardbred horses.. J Anim Physiol Anim Nutr (Berl) 2011 Jun;95(3):273-9.
  39. Ringmark S, Jansson A, Lindholm A, Hedenstru00f6m U, Roepstorff L. A 2.5 year study on health and locomotion symmetry in young Standardbred horses subjected to two levels of high intensity training distance.. Vet J 2016 Jan;207:99-104.
    doi: 10.1016/j.tvjl.2015.10.052pubmed: 26654845google scholar: lookup
  40. Ringmark, S. , Jansson, A. , & Roepstorff, L. (2014). Can locomotion asymmetry in young trotters predict early race performance? Equine Veterinary Journal, 46, 47. 10.1111/evj.12267_144.
    doi: 10.1111/evj.12267_144google scholar: lookup
  41. Ringmark S, Revold T, Jansson A. Effects of training distance on feed intake, growth, body condition and muscle glycogen content in young Standardbred horses fed a forage-only diet.. Animal 2017 Oct;11(10):1718-1726.
    doi: 10.1017/S1751731117000593pubmed: 28367770google scholar: lookup
  42. Ringmark S, Roepstorff L, Essu00e9n-Gustavsson B, Revold T, Lindholm A, Hedenstru00f6m U, Rundgren M, Ogren G, Jansson A. Growth, training response and health in Standardbred yearlings fed a forage-only diet.. Animal 2013 May;7(5):746-53.
    doi: 10.1017/S1751731112002261pubmed: 23228709google scholar: lookup
  43. Stefu00e1nsdu00f3ttir GJ, Gunnarsson V, Roepstorff L, Ragnarsson S, Jansson A. The effect of rider weight and additional weight in Icelandic horses in tu00f6lt: part I. Physiological responses.. Animal 2017 Sep;11(9):1558-1566.
    doi: 10.1017/S1751731117000556pmc: PMC5561439pubmed: 28320488google scholar: lookup
  44. Stefu00e1nsdu00f3ttir, G. J. , Jansson, A. , Ragnarsson, S. , & Gunnarsson, V. (2021). Speed of gaits in Icelandic horses and relationships to sex, age, conformation measurements and subjective judgesu2019 scores. Comparative Exercise Physiology, 17, 151u2013160. 10.3920/CEP200039.
    doi: 10.3920/CEP200039google scholar: lookup
  45. Stefu00e1nsdu00f3ttir GJ, Ragnarsson S, Gunnarsson V, Jansson A. Physiological response to a breed evaluation field test in Icelandic horses.. Animal 2014 Mar;8(3):431-9.
    doi: 10.1017/S1751731113002309pmc: PMC3942816pubmed: 24387835google scholar: lookup
  46. Unruh D, Srinivasan R, Benson T, Haigh S, Coyle D, Batra N, Keil R, Sturm R, Blanco V, Palascak M, Franco RS, Tong W, Chatterjee T, Hui DY, Davidson WS, Aronow BJ, Kalfa T, Manka D, Peairs A, Blomkalns A, Fulton DJ, Brittain JE, Weintraub NL, Bogdanov VY. Red Blood Cell Dysfunction Induced by High-Fat Diet: Potential Implications for Obesity-Related Atherosclerosis.. Circulation 2015 Nov 17;132(20):1898-908.
  47. Westervelt, R. G. , Stouffer, J. R. , Hintz, H. F. , & Schryver, H. F. (1976). Estimating fatness in horses and ponies. Journal of Animal Science, 43, 781u2013785. 10.2527/jas1976.434781x.
    doi: 10.2527/jas1976.434781xgoogle scholar: lookup
  48. WorldFengur (2020). The studbook of origin for the Icelandic horse. https://www.worldfengur.com/freezone.jsp?c=GB.

Citations

This article has been cited 3 times.
  1. Pratt-Phillips S, Munjizun A. Impacts of Adiposity on Exercise Performance in Horses.. Animals (Basel) 2023 Feb 14;13(4).
    doi: 10.3390/ani13040666pubmed: 36830453google scholar: lookup
  2. Sardeli AV, Castro A, Gadelha VB, Santos WMD, Lord JM, Cavaglieri CR, Chacon-Mikahil MPT. Metabolomic Response throughout 16 Weeks of Combined Aerobic and Resistance Exercise Training in Older Women with Metabolic Syndrome.. Metabolites 2022 Oct 30;12(11).
    doi: 10.3390/metabo12111041pubmed: 36355124google scholar: lookup
  3. Kang H, Zsoldos RR, Skinner JE, Gaughan JB, Mellor VA, Sole-Guitart A. The Use of Percutaneous Thermal Sensing Microchips to Measure Body Temperature in Horses during and after Exercise Using Three Different Cool-Down Methods.. Animals (Basel) 2022 May 14;12(10).
    doi: 10.3390/ani12101267pubmed: 35625113google scholar: lookup