Reference Values and Association of Body Weight, Age, and Sex With Echocardiographic Measurements in Non-Athletic Quarter Horses.
Abstract: Echocardiographic reference intervals for Quarter Horses are infrequently reported. Objective: To provide standard echocardiographic measurements for sedentary Quarter Horses and evaluate the relationship between physical characteristics (body weight, age, sex) and echocardiographic measurements. Methods: Forty-one sedentary Quarter Horses, free of cardiac disease, from a university research herd. Methods: A cross-sectional study evaluating standardized echocardiograms performed on sedentary Quarter Horses (41) between 2020 and 2022. Reference intervals were calculated for raw and weight-corrected values. Multiple linear regression was performed to evaluate the relationship between the physical characteristics (body weight, age, sex) and echocardiographic variables. Results: Multiple linear regression showed that every 100 kg of body weight was associated with a 3 (95% CI 1-6) mm thicker left ventricular free wall in systole (p = 0.02), an 8 (95% CI 2-13) mm larger left atrial diameter (p < 0.01), and a 4 (95% CI 0-9) mm larger pulmonary artery diameter (p = 0.04). Every year in age was associated with a 0 (95% CI 0-1) mm larger left atrial diameter (p = 0.02), a 0 (95% CI 0-1) mm larger aortic diameter (p = 0.01), and a 0 (95% CI 0-1) mm larger pulmonary artery diameter (p = 0.01). Left atrial to left ventricular ratio was 1 (95% CI -1 to 0) mm smaller in geldings compared to mares (p = 0.03). Conclusions: This study provides echocardiographic reference intervals for a cohort of sedentary Quarter Horses and clarifies the association with body weight, age, and sex with these variables.
© 2025 The Author(s). Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.
Publication Date: 2025-09-11 PubMed ID: 40931454PubMed Central: PMC12423106DOI: 10.1111/jvim.70237Google 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
Cite This Article
APA
Selecky ME, Louie EW, Donnelly C, Finno CJ, Morgan JM.
(2025).
Reference Values and Association of Body Weight, Age, and Sex With Echocardiographic Measurements in Non-Athletic Quarter Horses.
J Vet Intern Med, 39(5), e70237.
https://doi.org/10.1111/jvim.70237 Publication
Researcher Affiliations
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
MeSH Terms
- Animals
- Horses / anatomy & histology
- Horses / physiology
- Echocardiography / veterinary
- Male
- Female
- Reference Values
- Cross-Sectional Studies
- Body Weight
- Age Factors
- Sex Factors
- Heart / anatomy & histology
- Heart / diagnostic imaging
Grant Funding
- D21EQ-050 / Morris Animal Foundation
- University of California, Davis Provost Undergraduate Fellowship
- UC Davis Center for Equine Health
Conflict of Interest Statement
Authors declare no off‐label use of antimicrobials. The authors declare no conflicts of interest.
References
This article includes 35 references
- Reef VB, Whittier M, Allam LG. Echocardiography. Clinical Techniques in Equine Practice 3, no. 3 (2005): 274–283.
- Al‐haidar A, Farnir F, Deleuze S. Effect of Breed, Sex, Age and Body Weight on Echocardiographic Measurements in the Equine Species. Research in Veterinary Science 95, no. 1 (2013): 255–260.
- Vernemmen I, Vera L, Van Steenkiste G, van Loon G, Decloedt A. Reference Values for 2‐Dimensional and M‐Mode Echocardiography in Friesian and Warmblood Horses. Journal of Veterinary Internal Medicine 34, no. 6 (2020): 2701–2709.
- Grüner Sveälv B, Fritzon G, Andersson B. Gender and Age Related Differences in Left Ventricular Function and Geometry With Focus on the Long Axis. European Journal of Echocardiography 7, no. 4 (2006): 298–307.
- Hacker TA, McKiernan SH, Douglas PS, Wanagat J, Aiken JM. Age‐Related Changes in Cardiac Structure and Function in Fischer 344 X Brown Norway Hybrid Rats. American Journal of Physiology. Heart and Circulatory Physiology 290, no. 1 (2006): H304–H311.
- Durando MM. Cardiovascular Causes of Poor Performance and Exercise Intolerance and Assessment of Safety in the Equine Athlete. Veterinary Clinics of North America. Equine Practice 35 (2019): 175–190.
- Buhl R, Ersbøll AK, Eriksen L, Koch J. Changes Over Time in Echocardiographic Measurements in Young Standardbred Racehorses Undergoing Training and Racing and Association With Racing Performance. Journal of the American Veterinary Medical Association 226, no. 11 (2005): 1881–1887.
- Berthoud D, Schwarzwald CC. Echocardiographic Assessment of Left Ventricular Size and Systolic Function in Warmblood Horses Using Linear Measurements, Area‐Based Indices, and Volume Estimates: A Retrospective Database Analysis. Journal of Veterinary Internal Medicine 35, no. 1 (2021): 504–520.
- Patteson MW, Gibbs C, Wotton PR, Cripps PJ. Echocardiographic Measurements of Cardiac Dimensions and Indices of Cardiac Function in Normal Adult Thoroughbred Horses. Equine Veterinary Journal Suppl 27, no. 19 (1995): 18–27.
- Zucca E, Ferrucci F, Croci C, Di Fabio V, Zaninelli M, Ferro E. Echocardiographic Measurements of Cardiac Dimensions in Normal Standardbred Racehorses. Journal of Veterinary Cardiology 10, no. 1 (2008): 45–51.
- Navas de Solis C, Sampson SN, McKay T, Whitfield‐Cargile C. Standardised Exercise Testing in 17 Reining Horses: Musculoskeletal, Respiratory, Cardiac and Clinicopathological Findings. Equine Veterinary Education 30, no. 5 (2018): 262–267.
- Bonomo CCM, Michima LES, Miyashiro P, Fernandes WR. Quantitative Echocardiography of Athletic Quarter Horses/Ecocardiografia quantitativa de equinos atletas da raça Quarto de Milha. Ars Veterinaria 27, no. 4 (2011): 220–225.
- Beaumier A, Dixon CE, Robinson N, Rush JE, Bedenice D. Primary Cardiac Hemangiosarcoma in a Horse: Echocardiographic and Necropsy Findings. Journal of Veterinary Cardiology 32, no. 1 (2020): 66–72.
- Brinkman EL, Weed BC, Patnaik SS. Cardiac Findings in Quarter Horses With Heritable Equine Regional Dermal Asthenia. Journal of the American Veterinary Medical Association 250, no. 5 (2017): 538–547.
- Kohnken R, Schober K, Godman J. Double Outlet Right Ventricle With Subpulmonary Ventricular Septal Defect (Taussig‐Bing Anomaly) and Other Complex Congenital Cardiac Malformations in an American Quarter Horse Foal. Journal of Veterinary Cardiology 20, no. 1 (2018): 64–72.
- Nissen SD, Saljic A, Kjeldsen ST, Jespersen T, Hopster‐Iversen C, Buhl R. Cartilaginous Intrusion of the Atrioventricular Node in a Quarter Horse With a High Burden of Second‐Degree AV Block and Collapse: A Case Report. Animals 12, no. 21 (2022): 2915.
- Marr CM, Patteson M. Echocardiography. in Cardiology of the Horse (Elsevier Inc, 2010), 105–126.
- Long KJ, Bonagura JD, Darke PGG. Standardised Imaging Technique for Guided M‐Mode and Doppler Echocardiography in the Horse. Equine Veterinary Journal 24, no. 3 (1992): 226–235.
- Schwarzwald CC. Equine Echocardiography. Veterinary Clinics of North America. Equine Practice 35, no. 1 (2019): 43–64.
- Le Boedec K. Reference Interval Estimation of Small Sample Sizes: A Methodologic Comparison Using a Computer‐Simulation Study. Veterinary Clinical Pathology 48, no. 2 (2019): 335–346.
- Friedrichs KR, Harr KE, Freeman KP. ASVCP Reference Interval Guidelines: Determination of de Novo Reference Intervals in Veterinary Species and Other Related Topics. Veterinary Clinical Pathology 41, no. 4 (2012): 441–453.
- Fintl C, Krontveit R, Risberg H‐OS, Slack J. Two‐dimensional, M‐Mode and Left Atrial Velocity Echocardiographic Measurements in Healthy Norwegian‐Swedish Coldblooded Trotters. Journal of Veterinary Cardiology 1, no. 29 (2020): 60–73.
- Al‐Haidar A, Moula N, Leroux A. Reference Values of Two‐Dimensional and M‐Mode Echocardiographic Measurements as a Function of Body Size in Various Equine Breeds and in Ponies. Journal of Veterinary Cardiology 19, no. 6 (2017): 492–501.
- Huesler IM, Mitchell KJ, Schwarzwald CC. Echocardiographic Assessment of Left Atrial Size and Function in Warmblood Horses: Reference Intervals, Allometric Scaling, and Agreement of Different Echocardiographic Variables. Journal of Veterinary Internal Medicine 30, no. 4 (2016): 1241–1252.
- Navas de Solis C. Exercising Arrhythmias and Sudden Cardiac Death in Horses: Review of the Literature and Comparative Aspects. Equine Veterinary Journal 48 (2016): 406–413.
- Binda MB, Teixeira FA, Carvalho RS. Effects of 3‐Barrel Racing Exercise on Electrocardiographic and on Blood Parameters of Quarter Horses. Journal of Equine Veterinary Science 47, no. 1 (2016): 71–76.
- Williams TM, Bengtson P, Steller DL, Croll DA, Davis RW. The Healthy Heart: Lessons From Nature's Elite Athletes. Physiology 30 (2015): 349–357.
- Shave R, Howatson G, Dickson D, Young L. Exercise‐Induced Cardiac Remodeling: Lessons From Humans, Horses, and Dogs. in Exercise‐Induced Cardiac Remodeling: Lessons From Humans, Horses, and Dogs, vol. 4 (MDPI Multidisciplinary Digital Publishing Institute, 2017), 9.
- Maron BJ, Pelliccia A. The Heart of Trained Athletes: Cardiac Remodeling and the Risks of Sports, Including Sudden Death. Circulation 114 (2006): 1633–1644.
- Young LE, Rogers K, Wood JLN. Left Ventricular Size and Systolic Function in Thoroughbred Racehorses and Their Relationships to Race Performance. Journal of Applied Physiology 99, no. 4 (2005): 1278–1285.
- Young L E. Cardiac Responses to Training in 2‐Year‐Old Thoroughbreds: An Echocardiographic Study. Equine Veterinary Journal 30 (1999): 195–198.
- Buhl R. A Review of Structural Features of the Equine Athlete's Heart: Is a Large Heart an Advantage for Racing Success?. 2008.
- Trachsel D S, Giraudet A, Maso D. Relationships Between Body Dimensions, Body Weight, Age, Gender, Breed and Echocardiographic Dimensions in Young Endurance Horses. BMC Veterinary Research 12, no. 1 (2016): 226.
- Cornell C C, Kittleson M D, Torre P D. Allometric Scaling of M‐Mode Cardiac Measurements in Normal Adult Dogs. Journal of Veterinary Internal Medicine 18, no. 3 (2004): 311–321.
- Al‐Haidar A, Leroux A, Borde L. Relationship Between Echocardiographic Measurements and Body Size in Horses. Journal of Equine Veterinary Science 33, no. 2 (2013): 107–114.
Citations
This article has been cited 0 times.Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists