TONGUE-TIES Their place in racing in 2014  The use and efficacy of tongue ties has spawned much debate and in 2009 veterinarians at the University of Edinburgh led by Safia Barakzai conducted extensive research, which was published in the Equine Veterinary Journal, to evaluate the use of tongue ties on racing performance in thoroughbred racehorses. A second study published in the same publication in 2013 from the University of Guelph in Ontario, Canada aimed to assess whether tongue-ties contribute to upper airway stability and therefore allow horses to breathe easier.  That horse is making a noise” is an expression when heard around an exercising horse that sends shivers up the spine of anyone connected to the individual concerned. Tongue-ties (strips of material passed through the horse's mouth over the tongue and tied under the jaw) have been used for generations on racehorses worldwide. The rider has utilized a tongue-tie as a method to keep a horse from putting its tongue over the bit and thus avoiding loss of control. Additionally, when tongue-ties are used in an attempt to prevent dorsal displacement of the soft palate (DDSP), anecdotal reports as well as some clinical research have indicated this procedure is effective on some horses and ineffective on others. Tongue ties or “attache-langues” in the lexicon of Longchamp and Deauville are used in training establishments in North America and Europe on a daily basis and this article aims to explore this common practice.  Welfare Concerns  Applying a tongue-tie involves pulling the tongue as forward as possible and tying it close to its base around the lower jaw with a nylon strap with the tongue then pulled out to the side of the horse’s mouth. This practice of tongue-tying, however, has led to significant welfare debates, and in some countries the practice is illegal during the winter months because of the risk of frostbite to the tongue. In Switzerland, tongue tying is illegal all year around. It must be stated that the practice of tongue tying does not appear to cause the horse stress or pain and stimulates little reaction from the horse while their tongue is being manipulated. Obviously common sense must apply and tongue ties must not be fitted in times of inclement weather but this decision should be left in the hands of the horse’s handlers and in my opinion does not warrant further regulation.  The Edinburgh Study  Records were obtained from the Racing Post online database for case horses, which were defined as those that had raced while wearing a tongue-tie, and control horses, those that had never raced while wearing a tongue-tie. The case horses had to meet the following criteria: have at least five race starts before wearing a tongue tie in a race; had not raced during the 18 months prior to August 1, 2008 so as to ensure that their training and racing careers were finished; and had not raced before January 1, 1999 because the use of tongue ties was not recorded before that date. Each case horse was matched by gender and age with one or two unexposed horses if such matches could be found. The lifetime record for each control horse was examined to ensure that it had never raced with a tongue-tie and had started in at least five races before the date when its matched exposed horse raced with a tongue- tie.  Performances of all the study horses were analysed in three groups. Group 1 was made up of all case horses that wore a tongue-tie at least once, plus their matched controls. Group 2 was made up only of case horses that ran with a tongue-tie in place for three or more consecutive races after the first race in which a tongue-tie was used, plus their matched controls. Group 3 was made up only of case horses that ran with a tongue-tie in place for five or more consecutive races after the first race in which a tongue-tie was used, plus their matched controls.  The researchers gathered data on the total number of lifetime starts before and after the date of the first race where a tongue tie was used as well as total race earnings for the five starts before and five starts after a tongue tie was introduced. Data collected included age, number of starts prior to the first race using a tongue-tie, number of starts within 12 months after beginning to use a tongue-tie, and lifetime starts after beginning to use a tongue-tie.  Case horses tended to have fewer race starts than control horses before the first race using a tongue-tie. After the date when a tongue-tie was first used, horses in each set had about the same number of starts. However, case horses in groups 2 and 3 had significantly more starts than control horses in the 12 months following the first race using a tongue-tie.  For group 1, case horses were 1.85 times more likely than control horses to have improved earnings in their next three races after the date when a tongue-tie was first used.    For group 2, case horses were 3.6 times more likely than matched control horses to have improved earnings in their next three races after the date when a tongue tie was first used.  For group 3, case horses were 4.24 times more likely than matched control horses to have improved earnings in their next three races after the date when a tongue-tie was used, and 5.05 times more likely than matched control horses to have improved earnings in their next five races after the date when a tongue tie was used.  What does this tell us about the use of tongue-ties in racing thoroughbreds? Though previous research has shown inconclusive results regarding the efficacy of tongue-ties, this study seemed to indicate an advantage when certain groups of horses wore the device. The authors state, "The data here appear to show that tongue tie use has a beneficial effect on racing performance in selected horses that are perceived by their trainer to be afflicted with DDSP or which are run with a tongue tie in place to improve jockey control, and that this beneficial effect on racing performance is particularly marked for horses that run in at least three or five consecutive races wearing a tongue tie."  No attempt was made in this study to distinguish between horses with suspected or confirmed DDSP and horses that had a training or control problem.  The authors commented that while use of a tongue-tie appeared to enhance performance in some horses, the results of the study should not be seen as a promotion of tongue-tie use for normal horses as a performance enhancing aid.  Nasal strips and tongue ties in the US  During California Chrome’s bid for Triple Crown immortality during the spring of 2014 his trainer Art Sherman contacted the NYRA Stewards in the build up to the Belmont Stakes requesting permission to use nasal strips on the horse whilst competing in the race. In a Stewards house rule, nasal strips had previously fallen under the broad catch-all of a non approved device and was thus banned from use in New York, in sharp contrast to the policy in California where nasal strips can be and are used commonly within the rules of racing.  As the debate intensified, eminent North American veterinarian Dr. Scott Palmer was quoted “I recommend that the stewards at State- based thoroughbred racetracks discontinue their ban on equine nasal strips. Equine nasal strips do not enhance equine performance nor do they pose a risk to equine health or safety and as such do not need to be regulated.  “While there is research to indicate that equine nasal strips decrease airway resistance in horses and may decrease the amount of bleeding associated with EIPH to some degree, I am unfamiliar with any research indicating that equine nasal strips enable a horse to run faster with nasal strips than without them.  “In other words, there is no evidence they have a performance enhancing effect. Equine nasal strips do not pose a welfare or safety risk to the horse. They are applied to the top of the nose and anyone can see their use prior to a race. If improperly applied, equine nasal strips cannot interfere with performance. In my opinion equine nasal strips fall into the same category as tongue-ties.” The stewards considered Dr. Palmer’s advice and thus determined to allow the unregulated use of the nasal strips. It is clear that for ease of regulation that tongue ties and nasal strips were grouped together, however, they are very different devices and have no direct relationship with one another. Barakzai’s study showed that tongue-ties could have a performance enhancing effect on the racehorse, most likely in undiagnosed cases of palatial instability whereas the effect on performance of nasal strips is not scientifically proven to date.  The Canadian Study  Dr. Chalmers, Professor of Radiology at the University of Guelph, and her colleagues investigated 12 standardbred racehorses with and without tongue ties at rest. The team applied the tongue ties using a standard industry procedure, and then acquired ultrasound images of five different regions of the upper respiratory tract, including the positions of several bones and cartilages responsible for supporting the upper airway, attaching the windpipe to the back of the throat, and joining the tongue to the skull.  They measured these structures' positions and their relationship to each other using an ultrasound technique that Chalmers developed in earlier work. The study showed that when the horses' tongues were tied, the upper respiratory structures' positions were more compatible with upper airway stability and previous research by Chalmers and others suggests that the structural positions achieved by tongue-tying allow the horse to breathe better.  Better diagnostics, better results?  The key to improving the performance of our racehorses regardless of what device is used is an accurate diagnosis of the horse’s respiratory function. A study published in 2011 by Swiss surgeon Stefan Witte concluded that diagnosis of upper respiratory conditions based on owner-reported noise and performance history may result in an incomplete diagnosis.  This fact and the development of a technology which is non invasive, safe for both rider and horse, and highly informative, has led to the rapid increase in the amount of horses undergoing overground dynamic endoscopic examination as part of a complete evaluation of a horse’s upper respiratory tract. The dynamic overground endoscope involves a tiny camera that is inserted into the horse’s throat via his nose and the accompanying mechanism, which fits inside the horse’s bridle and saddle pad and transmits readings to a remote tablet. The equipment is lightweight, relatively unobtrusive and allows the use of the horse’s own tack making it quick and easy to fit to the patient.  Overground endoscopy is a highly useful tool as the relationship between the standard endoscopic examination of the horse at rest and how the horse’s larynx performs at exercise holds many variables. Many horses will show some laryngeal abnormalities on an endoscopic examination at rest but during exercise will have normal function and other conditions of the equine larynx only become apparent when the horse is fatigued and there is a change in exercise intensity, factors that can only be created while the horse is being examined while exercising.  In March 2013, the Equine Veterinary Journal published the results of a study conducted by the University of Glasgow in collaboration with a large thoroughbred training centre in the UK comparing the results of resting and dynamic endoscopy on a group of yearlings. Resting (pre- and post exercise) and exercising endoscopy was performed on 57 thoroughbred yearlings at a single training yard. Their conclusions were that there were significant variations in the results of endoscopy at rest and during exercise, which shows in an evidence based evaluation that resting endoscopy may not be sufficient to predict the occurrence of pathology during exercise.  Respiratory conditions that may be accurately diagnosed by dynamic endoscopy include dorsal displacement of the soft palate, laryngeal hemiplegia, aryepiglottal fold impingement and a plethora of other conditions, which may produce similar respiratory noises and are therefore typically difficult to differentiate by a traditional endoscopic examination. Performing exercising overground endoscopy examination in horses must also be viewed as a more cost effective option in comparison to treating a horse incorrectly without an accurate diagnosis. Dr Brett Woodie, of Rood and Riddle Equine Hospital in Kentucky and a world recognized expert in respiratory surgery, was recently quoted at the Annual American Surgery Convention stating that “more diagnoses are missed by not looking than not knowing” and thankfully with the development of over- ground endoscopy and its ease of use there is no longer reason for this to be the case.  Conclusion  The work done by veterinary scientists in Europe and North America has validated the long held view of horsemen that the application of a tongue-tie can improve racing performance in some cases. However, as with all medical conditions which are performance limiting and impact upon the health of the racehorse, an accurate diagnosis is crucial in ensuring our athletes are performing at their optimal level.  Thankfully with the development of a safe, non-invasive method of examining a horse’s wind, while it performs the discipline over which it will compete, trainers and veterinarians can allow our racehorses to fulfill their athletic potential by using the latest technology and research to practice evidence based medicine in appropriately selected cases.