The following articles and studies have been compiled from various sources to help educate the TWH owner and rider about the breed. While perhaps not breed specific, these articles address issues that TWH owners might come across when looking for information backed up by both experience and scientific fact. In keeping with the mission of this website, we hope our readers will learn about more positive methods for training and riding the TWHs, the effects of extreme shoeing and soring on the TWH, and physical and mental issues that relate to the health and longevity of the TWH. Feel free to contact us if you have any questions.
The Ranger Piece: Timing and Rate of Skeletal Maturation in Horses, With Comments on Starting Young Horses and the State of the Industry.
Dr. Deb Bennett, Ph.D., copyright 2008.
Quite possibly the most comprehensive study on bone growth in horses. This article explains how research shows that horses need to physically mature before being ridden and that riding horses at two years old can possibly be detrimental to their health.
Linda O'Leary: Hind End Veterinary Management. Since the hind end is the source for impulsion in the gaited horse, this article can help diagnose hind end issues and exercises to use to help them. While this article is not particular to gaited horses, the principles are the same and the exercises work for any breed.
The Energetic and Kinematic Consequences of Weighting the Distal Limb.
Equine Research Center and the Departments of Animal and Veterinary Science and Biology
California State Polytechnic Univesity, Pomona, California
McPhail Equine Performance Center, Michigan State University, Michigan
This study was performed to find out if adding weight to the horse's limbs would cause him to lift his feet higher and to what degree. As quoted from the article: "The results from this study emphasize the substantial energetic costs associated with alterations in the distal limb mass—an order of magnitude above the costs of placing that on the back of the horse. Changes in the inertial properties of the limbs also alter the kinematics and kinetics of the limbs. In order to control the movement of limbs with greater inertia, more energy must be generated and absorbed to control both flexion and extension throughout swing. Failing that, muscles and tendons may be exposed to excessive stretching leading to injury."
Gait Analysis: Opening Doors to Understanding the Gaited Horse.
Dr. Molly C. Nicodemus, Gaited Locomotive Research Program
Animal & Dairy Sciences, Mississippi State University, 2000
Click the blue Next button to read the entire presentation. Dr. Nicodemus with the Gaited Locomotive Research Program performed scientific analysis of the gaits, including timing of the footfalls and variations within the movement of each gait. She specifically focuses on the TWH and specifically studied the effects of the chain on the horse's pastern to see if it makes any difference in the height of the horse's step (slide 23). The study proved that wearing anything under a 10-ounce chain does nothing to enhance the front leg action of the horse. “Use of heavy weights (10 oz or 283 g) pastern chain weights significantly increased stride duration at the walk, but lower weights or pastern straps did not. Additional changes in hoof flight arc and head displacements were associated with heavy weights.” This means that the restricted size to the six-ounce chain that is used in the show ring does not affect the gait by itself. Therefore, we can deduce that chemicals must be being used on the horse’s pasterns for the chain to cause pain to force the horse to react.
NEW! Genetic key for smooth gaits discovered.
EQ Medical Front by Christine Barakat and Mick McCluskey, BVSc, MACVSc, Equus Issue 424
New research shows that the same genetic mutation is responsible for the tölt, the running walk and several other ambling gaits. See link below titled "Mutations in DMRT3 affect locomotion in horses and spinal circuit function in mice" for the research publication. Transcribed from Equus magazine (my apologies to the editors).
The Pernicious Effects of Extreme Shoeing, Soring, and Riding on the Horse and His Feet
Jamie Jackson, Sound Horse Conference 2010
Jamie Jackson, professional hoof care practitioner since 1975, was asked to talk about the effects of extreme shoeing and soring on the Tennessee Walking Horse. This comprehensive study explains how extreme shoeing, soring and the rider's position work and why they are a detriment to the horse. These images are of the PowerPoint presentation and his notes as included on each slide. (Click the blue Next button to scroll through the slides.)
NEW! Mutations in DMRT3 affect locomotion in horses and spinal circuit function in mice
Various authors, Nature 488, 642–646, 30 August 2012
New research shows that the ambling gaits in gaited horses is caused by a specific gene mutation. See above for the article from Equus titled "Genetic key for smooth gaits discovered" for their publication concerning this research.
Pedal Bone Rotation as a Prognostic Sign in Laminitis of Horses
John A. Stick DVM, Henry W. Jann DVM, MS, Edward A. Scott, DVM, MS,
N. Edward Robinson B Vet Med MRCVS Ph.D., 1982.
Research study that found pedal rotation in the hoof of more than 11.5 degrees causes loss of usefulness as a performance horse. It also focuses on this being a cause for laminitis. This study's findings are of major concern to the TWH breed since stacked TWHs are forced to stand on packages that force the pedal bone to point downward and there are more instances of laminitis in stacked horses than in flat shod horses. Although this study did not include TWHs, it did include Standardbreds, Morgans and Thoroughbreds, all foundations to the TWH breed; however, all equines share the same anatomy as far as leg and bone formation.
The Quest to Conquer Laminitis
Christy M. West, May 1, 2007
In this article, written after the Bluegrass Laminitis Symposium January 25 through 28, 2007, the author explores the use of venograms and how to read radiographs, the current methods being used to treat laminitis, and how to better the treatments. Most clearly is that the information in this article concerning the causes and symptoms of laminitis are some of the same issues that we find in gaited horses, particularly ones that have worn stacks or heavy shoes. The accompanying photograph shows how putting a horse's hoof at the type of angle required for the horse to wear stacks actually causes problems with the blood flow in the hoof. Click here for a larger view of the photo. (Please note: a membership to TheHorse.com is required to read this article. Membership is free and does not involve spam.)
NEW! Study: Underrun Heels Impair Horses' Hoof Loading Ability
By Alexandra Beckstett, The Horse Managing Editor Nov 28, 2013
Collapsed or underrun heels are a problem that manifests itself in poorly shod horses, racing horses, and horses wearing stacks and heavy shoes. The Auburn Study cover letter indicated that the veterinarians saw more instances of underrun heels in stacked horses. This study "recently examined the relationship between collapsed heels and hoof deformation."
Bitting: the Inside Story
Study examines bit action and its effects on the horse's mouth
Hilary M. Clayton, BVMS, PhD, MRCVS, December 2005
A comprehensive study, including x-rays, of the science of how bits fit in a horse's mouth and how they work. Different types of brands and mouthpieces were studied.
Bitting Actions and Reactions
Part 2 of a study on the science of bitting
Hilary M. Clayton, BVMS, PhD, MRCVS, May 2006
To follow the above study, this portion studies the evaluation of the movement of the horse's tongue and jaw in response to the presence of the bit, including x-rays. This also gives an interesting way to see how a bit should be positioned in the horse's mouth.
Saddle Fitting Guides
The Icelandic Horse Connection has done the hard work for us: found great guides online that help explain how to fit a saddle to your horse. The fit of your saddle is of utmost important to ensure safety of both horse and rider, to avoid back injuries of the horse, and to make sure your ride is comfortable for both you and your horse. It doesn't matter what breed you own; it's important to be sure your saddle fits.
Thermography in Diagnosis of Inflammatory Processes in Horses in Response to Various Chemical and Physical Factors.
Dr. Ram C. Purohit, Associate Professor
Department of Large Animal Surgery and Medicine
School of Veterinary Medicine, Auburn University, Alabama, 1978-1982.
Also known as "The Auburn Study," this study was performed to study the effects of chemical irritants and how they are affected by different sized chains. Due to this study, the chain weight limit in the show ring is now 6 ounces. Veterinarians who participated in the study did find more instances of laminitis, thrush, contracted heels, sheered heels, and quarter cracks in horses that are on stacks, as detailed in this cover letter. Click here for our comprehensive look at the Auburn Study.
The Role of Thermography in the Management of Equine Lameness.
Al Eddy, LM, Van Hoogmoed and JR Snyder, 2001.
Research study done at UC Davis Veterinary School at the UC of Davis in California. The use of thermography has been used in detecting soring by the USDA's VMOs at TWH shows throughout the country. Thermography detects changes in heat of the target surroundings, indicating inflammation and/or soreness. It has been questioned as to the reliability in this detection by the stacked TWH industry.
Mechanical nociceptive thresholds within the pastern region of Tennessee Walking Horses
K.K. Haussler, T.H. Behre, and A.E. Hill, 2008.
Research study done in order to test the use of an aglometer, which registers the amount of pressure placed on a surface. The test studied how much pressure it would take to elicit a pain response and then how much pressure should be used to digitally palpate a TWH's pastern to test for sensitivity. This device could become the standard for testing for sensitivity during the DQP inspection process so as to eliminate human error using digital palpation. The TWH industry has since rejected the use of the algometer.