EDINBURGH VETERINARY REVIEW

AND

Annals of Comparative Pathology.

ORIGINAL COMMUNICATIONS AND CASES.

Soundness in Horses. By JOHN GAMGEE, Principal of the New Veterinary College, Edinburgh.

ARTICLE VI.

Disorders of the digestive organs continued.-Bots in the stomach.-Perforation of the stomach.-Relapsing colic due to organic disease of the intestine, or to calculi. Hernia. The French law as to intermittent hernia.-Diseases of the liver.Hæpatirrhoea. - Abscess. — Gall stones. - Diseases of the urinary organs.Nephritis. Hæmaturia.-Albuminuria.-Calculi.-Retention of Urine.- Diseases of the Respiratory Organs.

BOTS IN THE STOMACH.-The larvæ of oestrus œqui are often found in large numbers adherent to the left or cardiac end of the horse's stomach. Several hundreds are found attached by the two short, black hooks which pierce the mucous membrane. The eggs of oestri are carried into the horse's stomach in the months of July and August, and in warm countries as early as June, and as late as September. The larvæ then remain fixed in the stomach until the succeeding spring, and when in excessive quantities, prevent horses getting into good condition.

The question as to whether bots exercise a salutary influence or not on the animal whose stomach they inhabit, has been settled by my father, so as to leave no doubt that Bracy Clark's notion as to the bots stimulating the stomach into healthy action were erroneous. In connection, however, with veterinary jurisprudence, the question has been mooted whether an animal could be killed by bots in its stomach. The instances in which they have induced fatal injury are so rare, and the cases recorded have been so complicated, as to enable us to determine that the lives of horses in this country are not endangered from the attacks of bots. The cases of perforation of the stomach that have been recorded belong to that class recorded by John Hunter, in which there is a post-mortem digestion of the coats of the stomach by the gastric juice. Such perforations occur in animals of all kinds, and without parasites in their stomachs. We cannot attribute any importance to the observations of those who have declared that the stomach was perforated in five or six places by bots, because no satisVOL. V. No. XXXV. MARCH, 1863.

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factory evidence is adduced to show that the gastric juice did not soften and destroy the walls of the stomach. In fact, we know that the bot does not knaw and lacerate, but holds on by firm hooks. It has the power of changing situation, and this explains the occasional adhesion of bots in the external wall of a perforated stomach.

The aperture due to the solvent force of the gastric structures has been described as an irregular, ragged hole, with gelatinous pulpy margins of great tenuity, which break down under the slightest force, a condition often extending over almost the whole of the organ. Dr Brinton, in his interesting work on "Diseases of the Stomach," of this lesion that "there are no evidences of inflammation on the one hand, or putrefaction on the other; the antiseptic action of the gastric solvent remarkably controlling the latter decomposition in most cases, and, as a rule, little congestion is present; the process apparently occurring at a date prior to the ordinary hypostasis that follows death, and preventing this change by a specific effect on the vessels or their contents. Hence the whitish or yellowish-grey appearance of these softened and perforated stomachs is a character which aids to distinguish them from ordinary specimens. But in many cases, even the perforation of the stomach by no means ends this process of solution, which extends to other structures thus exposed to the action of the gastric contents, and softens and erodes the neighbouring liver, spleen, or diaphragm, or even the lung itself, after the perforation of this septum."

It is interesting to observe that, in man as in the lower animals, this process of perforation usually attacks the cardiac end of the stomach, and may destroy the coats of the organ in several places simultaneously.

It is very important, in connection with the subject of veterinary jurisprudence, to point out as established truths, Firstly, That bots abound in the stomachs of all horses exposed in the summer months to the attacks of the bot fly, by being turned out to grass. Secondly, That the bots have no tendency to induce organic disease of the coats of the stomach, though, when in excessive quantities, they may prevent a horse getting into good condition. Thirdly, Perforations of the stomach, occurring when bots abound in this organ, do not differ from the perforations frequently witnessed as the result of the action of the gastric juice on the cardiac walls.

RELAPSING COLIC.-Horses are not unfrequently sold when they have been unusually troublesome to their owners, from repeated attacks of colic, which threatened to end in death. Several cases of this description have come under my notice. They occur in cart horses as a rule, and most frequently amongst millers' horses, and are due to calculi, which consist either in solid masses of excrement, or in phosphatic deposits around bits of metal, grit, &c., or in spheri

1 My father's experience on this point is most valuable. See Edinburgh Veterinary Review for July, 1858.

cal masses of undigested oat hairs, deposited in stratified layers. Lastly, There are concretions of a mixed character.

As a rule, the calculi are single, and may attain a very large size. Sometimes there are several calculi in the large intestine, and the veterinary surgeon is aided in his diagnosis by the discharge of a calculus per ano. The discharged calculi are usually of the phosphatic kind, requiring a long time to form. It is generally possible to determine if the calculus expelled has been the only one formed, for wherever the concretions are multiple they lose their spherical form by attrition against each other, and the calculus is seen flattened on one or more sides.

In the event of a horse discharging such a concretion, and suffering from attacks of colic, it is important to determine the length of time that the calculi take to form. That their formation is slow cannot be doubted. Sometimes the stercoral concretions, may attain great firmness in two or three months. Phosphatic calculi are much more slowly formed, but Fürstenberg has calculated that one of these concretions, weighing 14 pounds, could be formed in twelve months. is evident, that when a veterinary surgeon is called upon to give evidence as to the length of time an animal must have had a concretion in its intestine, it behoves him to inquire carefully into the history of the case, as well as taking into consideration the size, number, and character of the intestinal concretions.

It

When an animal dies of colic shortly after purchase, our attention is turned to the condition of the abdominal organs, with a view to determine if, from the existence of concretions in the intestine, or from some chronic organic lesion, we can obtain a clue as to the animal's unsoundness at the time of sale.

Some remarkable organic lesions have been found after death in cases of apparently simple colic. The only interest attaching to these cases in connection with the question of soundness, depends on the possibility of an animal being sold as a perfectly healthy one, and turning out the reverse. Several cases have been recorded in which the epiploic appendices have increased in size, and been transformed into pedunculated tumours, which have been coiled round the intestine, and have led to fatal obstruction. The annexed engraving (Fig. 1) is réproduced from one published in 1829, by Mr Goodwin. A good illustration of the difficulty experienced in determining the condition of internal organs in animals is afforded by a case which occurred in the Alfort College. An animal was killed for the purposes of the dissecting room, and after death an old-standing invagination was discovered. The annexed cut (Fig. 2) is a reduction of a drawing I made in Paris, and shows the portion of the coecum in the large colon.

a.-The strangulated knuckle of intestines which, from stricture and obstructed circulation, had become green and gangrenous.

b. The continuation of the portions of the ileum.

cc, dd.-Continuous portions of the same intestine (the ileum), also included within the stricture.

e. The chord which formed the stricture.

f. The fatty tumour hanging from the chord, which was in fact a hypertrophied epiploic appendix.

I have, in the next place, to notice a lesion which is much spoken of in France, where many entire horses are worked, and which in that country constitutes a defect, rendering an animal liable to be returned. It is

INTERMITTENT INGUINAL HERNIA.-This lesion consists in the temporary descent of a portion of small intestine into the scrotum. Such herniæ are reducible with a large opening, through which the intestine occasionally recedes. Huzard pointed out the fact, that inguinal hernia, having a tendency to disappear and recur, was very rare, and he considered that all small ruptures which would elude observation at purchase should constitute redhibitory vices. Galisset and Mignon, in their treatise on "Veterinary Jurisprudence," state that inguinal hernia which totally disappears, without direct reduction, must be very rare, but even by the French law an animal may be returned in which there is a hernia of long standing, that is apt to vary considerably in size at different times from change in the volume of its contents. The object of the law is to prevent fraud on the part of dealers who can resort to tricks, such as the reduction of a hernia, and sell a horse as sound.

Inguinal hernia occurs in geldings as well as stallions, but far more rarely. I remember seeing a case in Edinburgh in 1856, in which the hernia had to be reduced to relieve the severe symptoms of colic dependent on strangulation.

In examining entire horses, it is the duty of the veterinary surgeon to look at the scrotum, which is found large and tense in cases of hernia. The form of the included intestine is sometimes observed through the scrotum, and the opacity of the tumor, as well as the thickness of its neck, distinguishes the case from one of hydrocele.

Animals affected with hernia are apt to be seized with symptoms of strangulation when at work. The principal point of difficulty met with, in cases of intermittent hernia, has been to fix the date of the first appearance of the lesion to a period antecedent to the sale of the animal. In France the law is, that if an animal is seized with violent colic, and is recognised as having hernia within nine days after sale, it can be returned to the seller, and in the event of the animal dying, the purchaser claims the value. Although it is often impossible to declare that a hernia has pre-existed the time of sale, it is sometimes difficult to determine if a hernia is at all chronic, owing to the heat and engorgement, indeed, the symptoms of acute derangement which occur in connection with strangulation.

It is a rule which should especially be attended to in cases of colic in stallions newly purchased, that the inguinal rings are to be felt per rectum, so as to determine the existence or not of an inguinal hernia.

DISEASE OF THE LIVER.-Disputes have arisen from horses dying shortly after purchase, and the liver found much larger than natural. In one case, the liver weighed 32 lbs., or nearly three times its normal weight. Professor Dick has stated in a court of law, that he had