Diseases of the Horse's Foot Part 29

With regard to the wisdom of the latter proceeding, opinion seems to be divided. Personally, we hold an open mind concerning it. This much is certain: in many cases of laminitis--those cases which have their origin in overfeeding with an irritating food--there is already a strong predisposition to enteritis. The administration of aloes in this case is extremely apt to induce a fatal super-purgation. Aloes is, again, contra-indicated when the laminitis is a result of excessively long journeys, and the patient is already greatly exhausted. Neither can it be advocated in the laminitis occurring as a sequel to septic metritis or to pneumonia.

On the other hand, when the disease has occurred as a result of long standing in the stable and an overloaded condition of the bowels, or where one full meal of some constipating food, such as whole wheat, pea or bean meal, wheat or barley meal, has occasioned the attack, then a dose of aloes at the commencement of the treatment is productive of good.

Suitable febrifuges are found in pota.s.sium nitrate, pota.s.sium chlorate, sodium sulphate, or magnesium sulphate, either of which or a mixture of two or more of them, the animal will readily take in his drinking-water.

The administration of sedatives is also indicated. In this connection aconite will be found most useful. More especially in the early stages of the disease, when pain is excessive and the temperature high, will its good effects be noticed. This also the animal will often take in his drinking-water. We have been in the habit of so prescribing the B.P.

tincture in 1/2-dram doses three times daily. By its use the temperature is rapidly lowered, the pulse reduced in number and in fulness, and the pain in some instances perceptibly diminished. With others hypodermic injections of morphia and atropine have given equally satisfactory results.

Needless to say, good nursing is a _sine qua non_. During the first stages of the fever a light and easily digested diet should be allowed--bran-mashes, roots and gra.s.s when obtainable, and a carefully regulated supply of water. The animal should be warmly clothed and the box well ventilated, even to the opening of the doors and windows. Only in this way is pneumonia as a sequel sometimes prevented. The patient's comfort should be attended to in providing him with a suitable bed. Anything in the shape of long litter should be avoided. When nothing else is at hand, litter that has already been broken and shortened by previous use is best.

With this the box floor should be thickly covered, and matting of the material prevented by constant turning. A good bed for the horse with laminitis is peat-moss mixed with short straw. This, without being dragged into irregular heaps, remains springy and elastic with but little attention. Better than all, however, especially with good weather, is an open crewyard. Here the animal has an abundance of fresh air, has a bed that is always soft, and has plenty of room in which to get up and down with some degree of ease.

Leaving the dietetic and medicinal, we may consider other treatments of laminitis that come more particularly under the heading of operative.

The first matter that here demands our attention is that of allowing the exudate to escape at the sole. If after the expiration of three or four days pain and other symptoms of distress continue, then it may be judged that the inflammatory exudate has made its appearance. Operative measures allowing of its escape, though not giving absolute ease, do undoubtedly relieve the more marked expressions of suffering, and should be at once determined on. To do this completely it is necessary to cast the animal.

The sole is then thinned at the toe with the drawing-knife until the sensitive structures are reached. A flow of yellow and sometimes blood-stained discharge is immediately obtained, and the sole itself found to be underrun to a considerable extent. An opening sufficiently large to admit of free drainage (about the size of a half a crown-piece) is made, the wounds antiseptically dressed, and the hobbles removed.

If showing an inclination to do so, the animal should then be allowed to remain and rest. In one instance in which we so operated (a case of laminitis in the hind-feet alone), the relief given was at once manifested.

For three days previously the animal had remained standing in agonizing pain. On the fourth he was cast, and the discharge--partly inflammatory exudate, and partly a sanious foetid pus--liberated. The hobbles were removed, and the animal allowed to remain down while our attention was drawn to another case. This attended to, we walked back to the field where, our first patient was lying. His breathing, but a short time before distressedly short and catching, was now so slow and deeply regular that for one brief moment the thought flashed across our mind that he was dead.

He was in a _profound_ sleep.

Other operators sometimes give the exudate escape while making the grooves in what is now known as 'Smith's Operation.'

In this operation the hoof is so grooved as to allow of its expansion, so relieving the pressure on the sensitive structures within it. Incidentally, the inflammatory exudate is given exit.

[Ill.u.s.tration: FIG. 120.--DIAGRAM OF HOOF SHOWING THE POSITION OF THE THREE GROOVES MADE IN THE TREATMENT OF LAMINITIS.]

The animal is cast, the shoes removed, and three vertical grooves made in the wall. The first is cut down the centre of toe, extending from the coronet to the ground surface. The second is made to the right of this, and the third to the left, each following the direction of the horn fibres, and each distant about 2 inches from the first (see 1, 2, and 3, Fig. 120).

Each of the grooves must run completely from the coronary margin to the ground surface, and each should be carried through the substance of the horn until the h.o.r.n.y laminae are reached. This done, the underneath surface of the foot is grooved at the white line (see curved groove 4, Fig. 121) in such a manner as to entirely isolate the two pieces of horn _a_ and _b_ from the remainder of the hoof.

Expansion of the h.o.r.n.y box is thus brought about, while at the same time the semicircular groove at the toe is made deep enough to allow of the escape of the exudate.

If thought wise by the operator, the two pieces of horn _a_ and _b_ may be isolated, and the exudate given exit by making the fourth groove in the position of the dotted lines in Fig. 120--that is to say, at the lowermost portion of the sensitive structures. By this means the sole will be left intact.

[Ill.u.s.tration: FIG. 121.--LOWER SURFACE OF FOOT SHOWING POSITION OF THE GROOVES MADE IN THE TREATMENT OF LAMINITIS.]

Fuller instruction for making the grooves and the instruments required will be found described in Section C of Chapter X.

The animal should be afterwards shod, and the bearing on the portions _a_ and _b_ of the wall removed. Almost immediate relief is afforded the patient.

_Recorded Cases_.--1. 'On the evening of September 28 last, I was called rather hurriedly to attend a posting-horse which had just arrived from a twenty-one miles' journey, and was said to be "very ill." I lost no time in proceeding to the spot, and found my patient "very ill" indeed. No need for long consideration as to diagnosis; the symptoms showed at once that I had an uncommonly severe case of acute founder before me. On examination I found the pulse was 120, the respirations 100, and the thermometer 106 F.

The poor brute could not move, the fore-legs were well out before, and the hind-legs thrown back behind; in fact, he was, as one might say, propping himself up with his four legs!

'On examining his feet, I discovered what I had never either seen or heard of before--namely, _blood freely oozing out_ at the coronet of all four feet; if anything, the hind-feet were the worst, and, showing that this b.l.o.o.d.y discharge at coronets had commenced during progression and before he was stabled, the inside of the thighs were all shotted over with blood, which had been thrown up by his feet while he was trotting or walking. He was completely soaked all over with perspiration.

'My prognosis could not well be otherwise than unsatisfactory. I resolved, however, to do all I could to relieve the poor suffering brute. As a matter of course, jugular phlebotomy was utterly impracticable; so, to relieve the pressure in the feet, I had him (after, with extreme difficulty, removing the shoes) bled, or rather opened, at all four toes, and hot poultices applied. On opening the off-side toe, in both hind and fore feet, I found an escape of very dark-coloured blood, with a great many bubbles of gas, thus showing that the destructive process was fairly established in the two bony extremities mentioned. The near fore and near hind feet showed no signs of gas-bubbles on being opened at the toe.

'I gave a laxative in combination with a diffusible stimulant, and ordered doses of aconite and pota.s.sium iodide; I also applied strong sinapisms to each side, immediately behind the shoulders. After three hours I found my patient rather easier; respiration about 90, and temperature 104; willing to take a little water, and even attempted to take some hay. Ordered continued applications of hot water to the poultices at feet, and clothed him up for the night. Next morning there was little improvement; respirations over 80, and temperature 103.5. Continue same treatment.

Second morning, horse apparently easier; temperature 102.5, but very difficult respiration; laxative had operated during the night; ordered diffusible stimulants. About two hours and a half after my last visit, the horse turned round in his stall and dropped down dead!

'_History of the Horse_.--He belonged to an extensive horse-hiring establishment; was purchased a short time before for 60--a long price for a post-horse--had recently suffered and been off work from some "severe cold"; was taken out, and did forty-seven miles of a journey the day _before_ I saw him; on forenoon of the day on which he was attacked he did two or three short turns, and then twenty-one miles of a journey in the afternoon, during which he became so ill as scarcely to be able to conclude the twenty-one miles; this was the last turn he was to do. He was a grand stepper, and no doubt was pushed a little during this final journey, as the driver intended, after a short rest, to finish off with the twenty-six miles between this and home. With the short turns on the second forenoon, this would have been over 100 miles in less than two days, with a horse just out of a _severe cold_.'[A]

[Footnote A: _Veterinary Journal_, vol. xvii., p. 314 (A.E. Macgillivray).]

2. 'Whilst attending a patient on a farm on September 5 last my attention was called to a cart-horse, five years of age, that had been castrated in the standing position by a travelling castrator about ten days previously.

'I found the animal presenting the following symptoms: Head down, blowing hard, very dull, and disinclined to move, temperature 105 F., hard, rapid, slightly irregular pulse, membranes injected, appet.i.te lost; s.c.r.o.t.u.m, sheath, and p.e.n.i.s tremendously swollen, castration wounds unhealthy, and exuding a thin, reddish-brown discharge of a most foetid odour.

'The next day well-marked symptoms of laminitis were present. I finally ceased attending him about the middle of October, and at the end of that month he was turned out for the winter.'[A]

[Footnote A: _Veterinary Record_, vol. xiv., p. 649 (Charles A. Powell).]

3. 'On July 8 an interesting case of laminitis came under my notice. The subject was a mare, eight years old, which had been running on the common here for some months, and was taken up on the night of July 2 by a boy, who did not observe anything amiss with her. The following morning, on the owner going to the stable, he found the animal in great pain, and at once sent for me. I discovered her to be suffering from laminitis, and saw her again in the evening, when she was much worse. The attack proved to be a most severe one.

'The owner informed me that she had not been allowed any corn for two months, and that she had no distance to travel on the road from the common.

'Though on such a poor pasture, the mare was very fat; she had never been unwell before this attack.

'This is the first case I have seen of laminitis occurring when the animal was on gra.s.s.'[A]

[Footnote A: _Veterinary Journal_, vol. ix., p. 176 (W. Stanley Carless).]

B. CHRONIC.

1. CHRONIC LAMINITIS.

_Definition_.--A low and persisting type of inflammation of the sensitive structures of the foot, characterized by changes in the form of the hoof, and incurable pathological alterations within it.

_Causes_.--Chronic laminitis more often than not is a sequel to the acute form we have just described. With an attack of acute laminitis that defies treatment, and does not end in resolution in from ten days to a fortnight, then the chronic form may be expected.

The brittle horn, convex sole, and other changes we have described under Pumiced Foot may, however, be regarded as a chronic laminitis, and this condition, as we have already indicated in Chapter VI., may run a course slow and insidious from the onset.

_Symptoms_.--When the disease arises without previous acute symptoms, the first thing noticeable is an alteration in the gait. The animal begins to go feelingly, especially when first moved out from the stable. Our opinion is asked as to the cause of the lameness, and an inspection is made. With the changes in the form of the hoof as yet wanting, we have nothing to guide us, and other causes for the lameness suggest themselves, probably corns. Evidence of these is not forthcoming, and we in all probability withhold our opinion until a later visit. On the second or a subsequent call we are perhaps lucky enough to find our patient down. Diagnosis is then rendered easier. Made to rise, the animal stands in the att.i.tude we have described as indicative of laminitis. We have him walked and trotted out. The symptoms of tenderness disappear, and the animal soon goes fairly sound. He is, in fact, workable--that is, by anyone who is careless as to the comfort of his beast.

When following an acute attack, we have the most marked symptoms of pain and distress, somewhat abating after the second or third week. The walk, however, is still painful, and, for a short time after rising from the ground, even difficult.

In short, in both cases we have the horse going on his heels, with a walk that is painful, and with symptoms of pain that are most apparent when moved on after a rest.

Later, the changes in the form of the hoof begin to appear. It seems to have lost its elasticity, and is seen to be dry and chippy, and to have become denuded of its varnish-like outer covering.

In addition, it is of largely altered shape. The toe, by reason of the animal walking on his heels, and by reason of an increased growth of horn, becomes elevated, so that the front of the wall, instead of forming an obtuse angle with the ground, comes to run very nearly horizontal with it. The horn of the heels, as compared with that of the toe, takes on an increased growth. The same thing we have already indicated as happening at the toe, though in lesser degree. Taken together, this increased growth of horn at the toe and at the heels has the result of lengthening the diameter of the foot from before backwards, the transverse diameter remaining more or less normal. The hoof thus loses its circular build, and comes to approach nearer an elongated oval.

[FIG. 122.--FOOT BADLY DEFORMED AS A RESULT OF CHRONIC LAMINITIS.]

At this stage, too, the pathological 'ribbing' of the hoof is observable.

The outer surface of the wall becomes marked with a series of ridges encircling the hoof from heel to heel (see Fig. 81, which ill.u.s.trates a moderate deformity of the hoof occurring after laminitis). In the badly laminitic hoof, however, this deformity is largely increased, until in some cases the shapeless ma.s.s can hardly be likened to a foot at all (see Fig.

122).