THE HORSE’S MOUTH
The discussion of the subject of the horse’s mouth has been prompted by observing the thoughtlessness and carelessness of otherwise good horsemen and lovers of horseflesh with regard to the horse’s mouth. If a horse has a sore mouth he manifests it in some way unpleasant to his driver or rider, but it is rarely that an examination of that organ is made in order to determine the nature and extent of the trouble. Such an examination is not difficult to make by one at all accustomed to the handling of horses, and can be made as follows: Take the horse into a place in which the light is good. To examine the near side of the mouth, pass the left hand into the off side of it, grasp the tongue gently, and pull it a little to one side—it is not necessary to pull it out of the mouth—in order to expose the branch of the lower jaw, or bar, as it is sometimes called. The thumb of the right hand should be placed in the roof of the mouth so as to separate the jaws, when the part that the mouthpiece of the bit presses on can be easily scrutinized. The other side can be examined in the same manner by using the hands in the opposite way.
The soreness, however, is not always confined to the bars of the lower jaw, the result of the pressure of the bit, for it is not infrequently found that the lining membrane of the cheeks is excoriated by the bit forcibly pressing the cheeks against the anterior grinders. This form of injury is seldom found in a horse that readily bends his head upon his neck or “gets his nose in,” as it is often expressed, unless it is from the use of tight pulley-bridoon bearing reins, which is almost certain to cause it, particularly if a horse bores on it. In the majority of instances it is where a jointed or snaffle bit is used, when a horse “takes hold,” and in the case of one not inclined to “bend,” that the lining of the cheeks is injured. It can be readily understood, where a jointed bit is used on a horse that does not get his nose in, that when force is exerted upon the reins, it presses the cheeks directly against the teeth, and we can at once realize the great liability to injury of the soft and sensitive cheeks when pressed between two hard bodies, such as an iron bit and unyielding teeth, which frequently have sharp projecting hooks and angles at the very point at which pressure is brought to bear. Horses driven with tight over-checks are particularly subject to this form of injury to the mouth, as can be understood from the explanation already given. In horses that cannot be made to get their noses in, in riding or driving, and which show evidence of soreness of the mouth in the lining of the cheeks, the front grinders should be kept as smooth as possible. It is impossible for a horse to have a pleasant responsive mouth when the pressure comes upon the cheeks. Nature evidently intended the yielding lower jaw to bear the pressure of the bit, with the soft and elastic tongue to aid in avoiding injury to the sensitive structure which covers the branches of that jaw. Many horses which do not bend their heads upon their necks, when used with a snaffle bit can be made to get their noses in with a curb, which is consequently, when rationally used, the more humane and also the much more effectual in promoting style and action. Occasionally, however, one finds that a horse goes better in a snaffle than in any other kind of bit unless it is one with a smooth and slightly curved, unjointed mouthpiece.
In addition to those already referred to there are many other ill-results from sore mouths, and among the more serious of these are the restless and irritable habits horses develop when being ridden or driven out of the stable, such as going off with a rush, rearing, plunging and balking. A great deal depends upon the sensitiveness of the individual as to the manner in which he shows his restiveness and irritability when with a sore mouth again facing the bit. A horse of a good, mild temperament may do nothing but show a hesitation in going into the bit and if in double harness hang back for a time, or he will not go up with his mate. Others will go sideways, cross their jaws, press on one side of the bit, or toss their heads in an irritable manner that makes it almost impossible to guide them. High-strung, nervous, determined horses may show their irritability in the more dangerous manner of rushing, plunging or rearing. Drivers of horses are sometimes very much astonished to find a previously well-mannered horse go off with a rush, rear or plunge, but it is remarkable how seldom they think of looking to the mouth to find out the cause for the unexpected display of ill-manners, when in the majority of instances it is to be found there. Even when the lips are tinged with blood from the injured lining membrane it is seldom that an examination is made to determine the extent of the injury. Frequently when an injury to the mouth is pointed out to an owner it is thought lightly of, the extreme sensitiveness of that organ not being realized.
Pinches, abrasions and cracks about the commissures of the lips usually attract attention because they are easily observed, but they really, as a rule, do not cause nearly the amount of irritation and pain that an internal injury to the mouth does, and they are easily prevented by the use of a circular leather cheek piece on the bit. Some horses that show a disinclination to go into the bit for the first mile or two, after a time begin to pull, and the farther they are driven the more they pull. This is usually the result of a sore mouth, and veterinarians frequently have to remove small portions of bone which have been detached from the jaw by the extreme pressure of the bit. Bad “side-liners” are caused by a chipped jaw or else an extensive excoriation of the soft tissues on one side of the mouth where the bit exerts its pressure. In the healing up of such injuries the tissue with which nature repairs the breach seldom seems to attain the ability to stand the pressure of the bit to the same extent that one not so severely injured does. The fact that such permanent ill-effects are apt to follow injuries to the mouth from the bit should cause the exercise of due care when there is any evidence of soreness. Certainly high-couraged, ambitious horses are predisposed to injuries of the mouth, but they can be largely guarded against by the exercise of care, and it is very important never to disregard “soreness,” however slight.
There is probably no animal in which a bad habit is more apt to become confirmed than the horse, and the restless, irritable habits he is liable to develop on leaving the stable are among the most disagreeable. Some horses do not what is called “settle down” when first driven out, but either prance, hop or canter for a varying distance. This is generally accounted for by the owner as being evidence that the animal in question is “feeling too well,” or, in other words, is suffering from an exuberance of spirits. This may be the cause, but in the large majority of cases it is attributable to uneasiness in connection with the mouth. Sometimes this discomfort may not be the result of absolute soreness, as a change of bit may cause it. It may be noticed in an otherwise well broken horse where a curb bit is first substituted for a snaffle, particularly if it is placed too low in the mouth and if, as very often happens, the tongue is put over it, in which case a horse is very unlikely to go steadily, and his mouth is almost sure to get sore in a very short time.
The placing of the bit in a horse’s mouth is a very important matter in influencing his manner of going. Some horsemen say there is one proper position for a bit in a horse’s mouth and that it should always be placed in that position. My experience is that this is best determined by experiment with each individual, and one can tell, by driving or riding a horse a few minutes, as to where the bit should be placed in his mouth. It is usually best to place it rather high at first, particularly when changing to a curb bit, but if he keeps his tongue under it and does not respond readily to pressure, lower it as much as he will stand without showing restlessness. The lower the bit in the mouth, within certain limits, the better, provided the horse will keep his tongue under it and not fuss with it, and face it with a reasonable degree of firmness.
How frequently we see horses go off their feet when going well within their speed at the trot. Sometimes this is the result of excitability, but in nine cases out of ten it is due to a feeling of discomfort or want of confidence in connection with the mouth. Very often this is caused by the arrangement of the curb in giving too much leverage, especially if the hands of the driver are not good. Some horses that go unsteadily with the reins in the bar will go much better in the half-check, or it may be in the plain check, but very often the breaking at the trot is due to an injured mouth. Horse owners sometimes endeavor to overcome this tendency to breaking by giving long drives, and fatigue will temporarily overcome it as a rule, but there are horses that go unsteadily when almost jaded. This tendency can usually be overcome in a moderately worked horse if the bitting is made comfortable for him and the soreness of the mouth relieved.
Soreness of the mouth is by no means an uncommon one among the exciting causes of “interfering” and may frequently be observed even in well broken horses when a change of bit, particularly a change to a severe one, has produced some injury to the mouth. Fatigue, bad shoeing, rough or slippery roads, and the swaying of a heavy two-wheeler are all exciting causes of “striking,” and the awkwardness arising from an imperfectly made (not thoroughly bitted) mouth, with the incidental soreness, is an important factor.
Driving green horses in double harness is a very fertile cause of sore mouths. There are undoubted advantages in handling green horses in double harness, particularly shy, nervous ones, as the break horse inspires confidence in the green one and he is more easily controlled if badly frightened; but one can make more rapid progress in making a mouth in single harness, or in the saddle, than in double harness, for the opportunity of humoring it is better, and there is only one temper to consider. Trainers of green horses usually change the side horses are driven on every day, which is a good plan, as it tends to make them drive straight; but it is a tacit acknowledgment that there is more or less soreness of the mouth.
If the mouth is bruised or excoriated on the portion of the bars of the lower jaw where the bit presses, keep the bit out of it, if possible, until it heals. This need not prevent the horse being exercised, for if a suitable place is available, he can be lunged a sufficient time daily to keep him in condition and under control. The lunging line can be buckled in the noseband of the halter, and no bit need be used. If a suitable place for lunging is not available and it is necessary to lead the horse alongside of another that is ridden, it can be done without the use of a bit by using a tightly applied standing martingale, made with a headpiece and attached to a girth that is kept in its place by a crupper. The headline should be attached to the noseband of the headstall. In some instances changing to a bit that exerts its pressure so as not to interfere with the sore part will answer, as, for instance, the substitution of a snaffle for a Liverpool; but in most instances it is better to keep the bit out of the mouth altogether until it heals. When the mouth is sufficiently healed to stand the pressure of the bit again it is a very necessary precaution before driving for the first few times to take the sharp edge off the spirit of the horse by lunging him so that the sore part will not be so likely to be reinjured by the animal’s “taking hold.”
It is well to emphasize what has already been stated, that the front grinders should be kept in condition, so that they can inflict no injury to the cheeks, by having them thoroughly beveled or rounded off with the tooth rasp. This does no harm, provided it is done in a rational way, and is frequently of much benefit in preventing injury to the lining of the cheeks.