by Dr Shannon Lee, BVScIn order to digest their feed horses must first pick it up (prehension, done by the lips and front teeth) and chew it (mastication, done by the back teeth). Any problem with either of these steps affects the efficiency of the entire process. To use an analogy cars in a queue can only go as fast as the slowest moving car.
But speed is not the only issue here in order for proper digestion to occur feed must be reduced to a certain size before reaching the gut, food that is not reduced enough will not be properly digested and will be passed out in to the paddock.
The condition of the cheek teeth of a horse determines this size. The reduction in absorption of feed can be as much as thirty percent. So for this reason alone it is vitally important that all horses receive regular professional dental exams and treatment.
So what affects these two steps and what can be done about it?
Four things commonly affect prehension and mastication:
Pain - Any problem in the horse's mouth that causes pain will lead them to alter the way they eat and the speed at which they eat.
Trauma - As you are no doubt aware horses love to hurt themselves and other horses and the mouth is no different from any other part of the body, horse's frequently injure their teeth, tongue, skull and gums.
Disease - Diseases of the mouth such as gingivitis and periodontal disease are common in the horse and if untreated lead to premature loss of teeth and the potential for diseases of the vital organs such as the heart and kidneys.
Genetic disorders - Several genetic disorders occur commonly in the horse, the most common being parrot mouth or an underbite if left untreated parrot mouth leads to alterations in the wear of the back teeth and thus problems with both prehension and mastication.
Entire chapters of text books have been written on each of the headings above so obviously there are a lot of details that we don't have room to cover here but I will give a brief outline of some the conditions that occur.
There are numerous sources of pain in the horse's mouth. Some of the more common ones include ulcers to the cheeks and tongue caused by sharp enamel points, incorrect use of the bit, gingivitis and periodontal disease, fractures or loose teeth, bit contact with wolf teeth, impacted teeth and lacerations to the tongue.
There is not enough room to cover the treatment of these conditions, but what is essential is a thorough exam of the whole horse. Followed by an external exam of the head and then a complete oral exam with a good light source, a full mouth speculum, a mirror and probe and possibly other tools such as x-rays. Only then can a diagnosis be made and treatment started.
Trauma can basically be divided into recent and long term as well as major and minor, recent trauma can often be treated while long term trauma is usually managed.
Major trauma may require immediate surgery while minor trauma might be treated with pain relief and monitoring. Examples of major trauma include jaw fractures, avulsion of teeth and severe cuts to the tongue or cheeks. Minor trauma includes bumps and scratches and chipping of teeth
Some oral diseases are extremely common such as periodontal disease (disease of the structures anchoring the tooth) while others like neoplasia (cancer) are relatively rare, however none can be diagnosed and treated without a proper oral exam.
Genetic disorders like parrot mouth can often be corrected and certainly need to be managed throughout a horse's life, but require a diagnosis at or soon after birth for the best outcome. So dental checks for foals are recommended.
With the current high feed prices and the severe pain and suffering caused to horse's through dental conditions I encourage all horse owners to take responsibility to ensure their horse's receive the best possible dental care and maintain optimal digestive function.