When searching for answers as to why an equine athlete's performance has suddenly declined, many owners and trainers will look for problems from head to toe. But one place they sometimes neglect to check is the horse's mouth, where many dental issues can cause a performance horse to work at a less than optimum level.
During a presentation at the 2011 Rood & Riddle Equine Hospital Sport Horse Health Symposium, held Nov. 2 at the Kentucky Horse Park in Lexington, R. Brad Tanner, DVM, an equine practitioner and associate at Rood & Riddle, discussed the impact of dental health on the equine athlete.
Tanner began by discussing a few different indicators of equine mouth pain while a horse is working, such as:
- Opening the mouth;
- "Lugging out";
- Pinning the ears;
- Head tossing;
- Coming ahead or behind the bit; and
- Leaning on the bit.
Tanner explained that these signs can have a variety of causes from natural processes that just need some attention to problems brought on by ill-used or ill-fitting bits.
Bit Pain--With more than 1,200 different types of bit to choose from, Tanner noted, finding one that works perfectly in a horse's mouth is a challenge. When examining a performance horse, Tanner often evaluates how the bit the animal wears is impacting his mouth.
He explained that from a veterinarian's perspective, there are several considerations to make when evaluating how a bit functions in a horse's mouth including:
- Materials used in the mouth piece (such as steel, rubber, or different types of metal);
- The type of mouth piece (such as single jointed, double jointed, or mullen mouth); and
- Whether the bit encourages a wet or dry mouth ("For the horse to work properly, you've got to have a wet mouth and salivation," he said. "There are too many delicate tissues to have a dry mouth.").
"The bit has several pressure points including the tongue, hard palate (roof of the mouth), bars (area between the incisors and the grinding cheek teeth), lips, chin, nose, and poll," Tanner explained. When a bit is used and fitted properly, horses tolerate its pressure; when improperly used or fitted, however, excess pressure can cause several problems in the horse's mouth.
Excess pressure on any of the aforementioned pressure points can lead to sores, ulcers, or laceration, all of which will cause the horse discomfort. Additionally, bits can pinch the horse's cheeks with similar effects, he said.
Tanner also cautioned not to assume a seemingly gentle bit won't damage a horse's mouth. Accompanied by images of radiographs, Tanner explained one evaluation of three mild bits that revealed a single jointed loose ring snaffle yielded much less pressure on the tongue than did a double jointed loose ring or a double jointed D-ring snaffle when the same amount of tension was applied via the reins.
Tanner also noted that while bits with solid mouth pieces and a low port are often thought of as less severe than solid bits with high ports, those with very low ports actually cause more pressure on the tongue than do those with high ports. He warned that bits with very high ports have more risk of damaging the soft palate, however, so use caution when selecting a ported bit.
Physical Pain--He reminded attendees that, especially when working with young horses, nature could be playing a role in bit discomfort: "At two, remember, the baby teeth are coming out. This could cause tension or pain."
Retained caps and baby teeth can be a significant source pain in young horses between 2 and 6 years of age, he explained. These horses should be examined twice yearly to ensure the permanent teeth are erupting properly and that the deciduous (baby) teeth are being shed, he advised.
Additionally, as horses grow older, Tanner recommends having a veterinary dental practitioner create a bit seat (when the first upper and lower cheek teeth are slightly rounded) to reduce the potential for sharp points interfering with the bit.
Finally, he explained that proper poll flexion can only be achieved with properly floated teeth. Excess tooth growth interferes with the horse's top jaw moving forward, which is required for poll flexion; the long teeth become locked, making it impossible for the horse to flex properly.
Take-Home Message
Tanner emphasized the importance of dental health and proper bitting in keeping the performance horse working at his highest potential. The best thing to promote good dental health and to ensure that your equine athlete is oral pain-free is to have your veterinarian perform routine dental exams, he advised.
"Think about what's going on inside the horse's mouth if he's tossing his head," he said. "If you eliminate mouth pain, then you can start thinking about the whole body approach."
Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.