Researcher Profiles

Dr. Heather J. Chalmers

Heather Chalmers

"As a veterinary clinical researcher, I advance understanding and diagnostic capability in equine upper airway diseases, both for the benefit of veterinary medicine and as a model of human disease. My long term vision is to advance the use of ultrasound as a non-invasive marker of muscle atrophy in veterinary and human disease. Towards this goal, my current project, which forms part of my PhD thesis, is aimed at detecting roaring in horses prior to the onset of clinical disease."

YouTube logo Dr. Chalmers discusses her research in our special feature

Education: BSc (Hons) and DVM Univeristy of Guelph

Residency: Cornell University, Ithaca, NY

Specialty: American College of Veterinary Radiology


Significant research accomplishments:

  • Originated the equine laryngeal ultrasound technique, which has found broad clinical application in equine hospitals throughout North America and around the world.
  • Discovered a conformational difference in horses with dorsal displacement of the soft palate (DDSP). This was the first report that successfully differentiated affected horses from unaffected horses at rest and has led to advanced understanding of the pathogenesis of DDSP in addition to ameliorating the diagnostic process for DDSP.
  • Proved the efficacy of a tongue tie in favourably altering laryngo-hyoid conformation in horses, providing the first ever evidence that this commonly applied and controversial piece of racing tack may positively contribute to upper airway stability.

Degrees: BSc, DVM, Dipl. ACVR

Position: Assistant Professor, Department of Clinical Studies, Ontario Veterinary College, University of Guelph

Original research papers: (*indicates primary investigator)

1. Chalmers HJ, Dykes NL, Lust G, Farese J, Burton-Wurster NI, Williams AJ, Todhunter RJ*. Assessment of bone mineral density of the femoral head in dogs with early osteoarthritis. American Journal of Veterinary Research, 2006;67(5).

2. Chalmers HJ, Scrivani PV, Dykes NL*, Hubble L, Hobbs J, Erb HN. Identifying removable radioactivity on the surface of hospitalized cats during the first week after I131 treatment. Veterinary Radiology and Ultrasound 2006;47(5).

3. Chalmers HJ, Cheetham J, Yeager AE, Ducharme NG*. Ultrasonography of the equine larynx. Veterinary Radiology and Ultrasound 2006;47(5).

4. Chalmers HJ, Dykes NL*, Erb HN, Hubble L, Scrivani PV. Agreement between two survey meters for measuring radioactivity in cats after iodine 131 treatment. American Journal of Veterinary Research, 2007;68(4).

5. Strand E*, Fjordbakk CT, Holcombe SJ, Reisberd A, Chalmers HJ. Effect of poll flexion and dynamic laryngeal collapse on tracheal pressure in Norwegian Coldblooded Trotter racehorses. Equine Veterinary Journal; 2009 41(1).

6. Chalmers HJ*, Yeager AE, Ducharme NG. Ultrasonographic assessment of laryngohyoid position as a predictor of dorsal displacement of the soft palate in horses. Veterinary Radiology and Ultrasound, 2009; 50(1):91-96.

7. Rioja E, McDonell WN, Kerr CL*, Dobson H, Konyer NB, Poma R, Chalmers HJ, Noseworthy MD. Effects of hypercapnia, hypocamnia, and hyperoxemia on brain morphometrics determined by use of MRI in isofluorane anesthetized dogs. American Journal of Veterinary Research 2010; 71(9);1011-1018.

8. Grimmett SG, Chalmers HJ, Wolf JC, Bowser PR*. Spinal deformity in triploid grass carp Ctenopharyngodon idella (Valenciennes). Journal of Fish Diseases 2010; 34(3):217-25.

9. Volk GF, Wystub N, Pantel M, Kim JH, Chalmers HJ, Guntinas-Lichius O*. Functional sonography of the muscles in facial nerve paralysis, Klinische Neurophysiologie, 2011; 1, 42: 37-90.

10. Rioja E, Sinclair M*, Chalmers H, Foster RA, Monteith G. Comparison of three techniques for paravertebral brachial plexus blockade in dogs. Veterinary Anaesthesia and Analgesia. 2012; 39(3).

11. Fjordbakk CT, Holcombe SJ, Fintl C, Chalmers HJ, Strand E*. A novel treatment for dynamic laryngeal collapse associated with poll flexion: the modified checkrein. Equine Veterinary Journal; 2012; 44(2).

12. Lerer A, Nykamp SG, Chalmers HJ*. The OVC Hip Certification Program – repeatability and comparison to the Orthopedic Foundation for Animals. Candian Veterinary Journal, accepted for publication, April, 2012.

13. Chalmers HJ*, Farberman A, Allossery A, Viel L. Use of a tongue tie alters laryngo-hyoid position in the standing horses. Equine Veterinary Journal, accepted for publication, June 2012.

See Dr. Chalmers as she discusses her current research in our special feature REPORT ON RESEARCH