Part 16

Laryngeal paralysis and roaring often follow laryngitis in strangles.

Pulmonary Symptoms in Strangles. Tracheitis and bronchitis are forms of extension of strangles from the upper air passages, and pneumonia follows of virtual necessity. In many cases these are primarily dependent on the descent into the lungs of the infecting discharges, complicated in many cases by the inhalation of food materials. There are the usual symptoms of broncho-pneumonia complicating those of strangles and the percussion and auscultation signs usually imply circumscribed areas of congestion and consolidation with intervening areas of pervious lung. There may be at such points the blowing or mucous râles of bronchitis, the sibilant sounds of emphysema, the crepitation of congestion and the abnormal clearness of sounds carried from distant organs through the consolidated lung. On percussion there may be the non-resonance of the consolidated areas, and the excess of resonance over emphysematous portions or open gas-filled vomicæ. In these last cases there may be an amphoric sound on auscultation and a crack-pot sound on percussion. These pulmonary lesions are often fatal, or the recovery is slow on account of a succession of lobular congestions and abscesses.

Abdominal Symptoms in Strangles. The abdominal lesions in strangles are usually secondary, the infection reaching the part through the blood, or by the lymphatics from a castration or other wound, or from infection by coitus. The phlegmon and abscess may be in the mucosa, especially in the agminated or solitary glands, in the adjacent lymph glands at the connection with the mesentery and in those of the mesentery itself. The animal is dull, listless, with dry, staring coat, tympany and slight colicy pains after eating, costiveness, retracted, tender abdomen, insensible loins, and groaning when rising, when walking down a steep incline, or turning in a very narrow circle. These symptoms following an apparent or partial recovery from strangles are significant, and rectal examination may detect a hard, tender mass connected with the bowel or mesentery.

If rupture takes place into the peritoneum there is general infective inflammation of that structure with sudden access of fever, marked prostration and an early death. In more favorable cases its adhesion to the bowel or to the abdominal wall opens the way for rupture into the gut or externally and there may be a slow healing of the cavity by granulation. It may be a month or two before such an abscess opens and for a length of time thereafter the health is poor, and the animal lacking in condition and endurance.

When the abscess is formed in the liver there is high fever with shivering fits, irregularity of the bowels (bound up or loose), dusky or yellowish hue of the visible mucosæ, anorexia, followed by peritoneal infection or pyæmia (secondary abscesses).

Abscess of the pancreas or spleen is even less definite in symptoms. These may terminate in rupture and peritonitis, or the splenic abscess may become chronic and indolent and in a measure harmless.

Perirenal Abscess is betrayed by specially sensitive loins, stiffness and groaning in rising or in turning sharply on himself, drooping of the back under a load, and by albuminous urine. In a small animal the part may be reached and the tenderness ellicited by handling.

Cutaneous Symptoms in Strangles. Though by no means a common form, strangles sometimes attacks the skin, more particularly that of the face, head and neck, appearing in the form of pustules or small abscesses, or it may be of a rounded nodular elevation, which may disappear without forming either vesicle or pustule. The points of election are around the lips, nose and eyes, upon the mucosa inside the lips, along the line of the facial lymphatics running toward the submaxillary gland, and at points where there is special friction, as under the halter, collar, saddle, crupper, in the hollow of the heel, under the tail, on the perineum, in the groin and axilla. They may extend more or less up the limbs, or around the point of primary attack attended by more or less engorgement. When this engorgement has reached extensive dimensions and is mixed with sanguineous extravasation it is considered as having merged into petechial fever.

Symptoms of Coital Infection. From four to seven days after copulation there appear fever, dullness, stiffness, anorexia, swelling and heat of the lips of the vulva, a yellowish opaque discharge from its lower commissure, a deep dark red blush of the mucosa, with points of distinct infiltration and thickening, developing into vesicles and pustules. The perineum, the groin and mammæ often show an extension of the congestion and eruption. In exceptional cases deep abscesses form and Letard records a fatal case with extensive suppuration among the muscles of the hind limbs and the haunch, inside the pelvis and along the line of the aorta.

Symptoms of Nervous Lesions. The lesions of the brain and spinal cord are usually secondary and often appear when the less dangerous superficial manifestations, are tardy and indolent, when the exudates are indurated and indisposed to soften. There may be violent delirium, pushing of the head against the wall, movements of the limbs as if walking or trotting, roaring, plunging, striking with fore or hind feet, trismus or other muscular spasms. More frequently there is great dulness, prostration, debility, vertigo, drowsiness, amaurosis, paraplegia, general paralysis, coma. If the lesion is in the spinal cord the spastic or paralytic symptoms are likely to be confined to the hind parts.

Fulminant or Septicæmic Form. Bigoteau describes a rapidly fatal, septicæmic form, with sudden onset, anorexia, extreme prostration, uncertain stumbling gait, a deep blue color and ecchymosis of the visible mucosæ, violent heart action, pulse weak and small, hurried breathing (45 per minute) temperature 102° to 106° F., often inability to rise and death from asphyxia in from two to five days.

Diagnosis. In mild and regular cases this is easy. The attack in rapid succession of all the young, and still susceptible horses in a stable or locality, and the uniform coincidence of a profuse nasal catarrh, and the formation between the branches of the lower jaw, of a diffuse, hot, painful swelling rapidly advancing to suppuration and discharge are virtually conclusive. Simple catarrhs even if infective and attacking all young horses do not cause phlegmon of the submaxillary lymph glands as occurs in the great majority of cases of strangles. Glanders which is attended by both nasal discharge and submaxillary swelling, is slower in its onset, usually with little or no fever, has usually a more adhesive discharge, ragged, unhealthy ulcers on the nasal mucosa with a disposition to extend, often it shows cord-like thickening of the lymphatics on the side of the face, and the submaxillary swelling is smaller, made up of a number of small, hard, insensible rounded nodules which show virtually no tendency to suppurate. (See diagnosis of glanders). In cases of doubt it may be advisable to inoculate a Guinea-pig and a white mouse. The Guinea-pig resists a small dose, while the mouse forms abscess in the seat of inoculation in the dependent lymph glands. The Guinea-pig is very susceptible to glanders, and the white mouse immune. Or mallein may be used.

Prognosis. The mild type of strangles almost invariably terminates favorably. In the irregular types with internal abscess the prospect is grave in ratio with the size and multiplicity of the foci and the vital importance of the organ invaded. In 15,421 cases collected by Friedberger and Fröhner, and representing the total in a series of outbreaks, but 3 per cent proved fatal. Much, however, depends on the special potency of the germ. Horses contracting this in a particular year or from a given stable in the same year convey the disease to others in a malignant form, while others that contracted it in another year or a different stable infect with the mild form only.

Prevention. In the older countries horsemen too often accept strangles as inevitable. They expect that all horses will have it sooner or later, and it is not worth while to guard against it. The too absolute doctrine of the identity of the germ with the microbe of erysipelas, puerperal fever, contagious pneumonia, influenza, of the suppurations of the limbs and feet in sheep and cattle, and other streptococcic infections seems to corroborate this view. But on the other hand the absence of strangles from given countries like Iceland where erysipelas and its coadjutors are common, its absence from secluded breeding farms and districts in America, though prevailing all around them, the rapidity of its spread when introduced in a sick colt, and the entire failure to extend in the same way from an erysipelatous man to susceptible young horses with which he comes in contact show that preventive measures may be successfully applied for its restriction and extinction. The conceded family resemblance of the microbes and the experimental production, by their inoculation, of lesions showing many points of similitude leave them still sufficiently distinct in their pathogenesis to warrant measures for the suppression of the variety which produces strangles.

Precautions for the private owner. During the existence of strangles in the district, exclude strange horses, asses or mules from the farm or stable. Keep young susceptible horses from public stables or yards (livery, feeding, training, fair, market, and above all, dealers’ and sale stables) and even from public drinking troughs and buckets used in common. Provide against their contact with manure from strange or infected stables, or with pastures, fields and wagons on which this has been put, also against the use around the stable or on fodder of forks or other implements that have been used for such manure. Avoid hay or other fodder or litter from a strange barn or one that is open to any suspicion of infection. Avoid running water that has drained land, stables, or yards where strange horses have been, or those open to suspicion. In shipping by car or other public conveyance disinfect the latter before the animal is loaded. If a second hand wagon, shafts, pole, harness, blanket or other object is brought on the place or used, disinfect the same before using.

Measures for Sanitary Police. Make it compulsory to report, under penalty for failure, all cases of strangles, or of horses with nasal discharge, or submaxillary swelling. Forbid removal from the stable, or secluded enclosure, of all horses, etc., suffering in this way or which have been pronounced by the official veterinarian to have strangles. Provide for exclusion of all other solipeds from such stables, or from contact or dangerous proximity to animals held in them, also from infected yards, parks, cars, boats, etc. Close public drinking troughs during an epizoötic; let each owner use his own bucket. Circumstances may demand closure of public feeding stables as well. Forbid, under penalty, sale, exposure or movement on any public highway or unfenced place of any infected (diseased or exposed) soliped. Enjoin certificate of sanitary conditions of stable and stud with each animal sold. Close dealers’ stables, or forbid any sale from them until all infection has ceased and the buildings have been thoroughly disinfected. Compel thorough disinfection of stables, yards, cars, boats and other public conveyances that may be open to reasonable suspicion of infection.

Immunization. An attack renders the subject immune, but this may be early overcome by marked change of location, and exposure to a virus of greater intensity or modified quality. Besides the crude and reckless Russian method already referred to, direct inoculation of the virulent products has been often resorted to from the time of Gohier onward, in the different countries of Europe. By selecting the matter from the abscesses or nasal discharge of a mild epizoötic, and preserving the inoculated subjects in clean, dry, pure aired stables, on nourishing diet, and under the best conditions of hygiene, a fair measure of immunity was conferred with absolutely no loss. The same as after casual cases, second attacks will sometimes be shown, but even in severe outbreaks, of a less violent type. The pus from the abscess, or the preceding exudate in the swelling may be simply rubbed on the nasal mucosa, or injected subcutem in another part of the body. In many cases there follows merely a local cellulitis, while in others the general infection leads to the nasal discharge, with or without the submaxillary abscess.

This method is open to the individual owner where no concerted effort is made to stamp out the infection. When, however, police measures for suppression are in force, it must be strictly prohibited, or adopted only under official control, and with absolute seclusion and thorough disinfection.

Treatment. In mild regular cases hygienic measures only are demanded. Cleanliness, dry stalls, pure air, warmth (a sunny exposure if available), nourishing, easily digested food, (grass, green corn stalks, bran mashes, roots, carrots, turnips, apples, potatoes, ensilage, scalded oats or hay) and pure water, or linseed tea, grooming and, in cold weather, blanketing may suffice. Rest is indispensable, though exercise may be allowed in a sheltered or sunny field or yard in fine weather.

Castrations and all other surgical operations are forbidden.

For costiveness or tardy action of the bowels 1, 2 or 3 ozs. of sulphate of soda may be allowed daily in the drinking water.

To soothe the inflamed air-passages it is well to steam them with the vapor of hot water to which has been added an antiseptic such as oil of tar, tar, phenic acid, or creolin. This may be placed in a bucket, and a bag with its bottom cut so as to form a tube drawn over the bucket and nose of the horse. It may be continued an hour or more at a time, or a nasal douche of creolin (1:100) may be employed. In case of tardy softening of the submaxillary swelling it may be assiduously fomented, or covered with a linseed meal or other poultice to which a little antiseptic (carbolic acid, creolin) has been added. It may be applied on a cotton hood having holes for eyes and ears and furnished with ends to tie back of the ears and down the middle of the face. If still indolent the swelling may be rubbed with soap liniment or smeared with soft soap, or finally a cantharides blister may be applied.

As soon as any indication of softening or fluctuation is detected a free incision should be made to allow the exit of the pus. This further tends to hasten the liquefaction and removal of the adjacent exudate. If the pus lies near to the surface, with little more than skin to penetrate, it may be freely incised with one thrust of the knife, but if there is intervening glandular or other tissue, the skin only should be first incised, and the connective tissue bored through with the finger nail, or the point of a sterilized director, or of closed scissors. In this way the important vessels, nerves and salivary ducts are pushed aside and troublesome bleeding and saliva fistula alike avoided.

Fever usually subsides on the opening of the abscess, but if it fails to do so, or if it reappears from slight absorption of septic matters it may be desirable to favor elimination by small doses of sodium bicarbonate, ammonium chloride, or potassium nitrate. In extreme cases a few doses of acetanilid may be given, or full doses of quinia.

When the discharge from nose or abscess threatens to persist, such agents as sulphur, yellow or black sulphide of antimony, are given with bitters, but a more prompt effect can usually be had from injections of weak solutions of creolin, cresyl, lysol, etc. When the cough is troublesome it may be quieted by belladonna, or, in case of weakness of the heart, by digitalis.

The various complications require treatment appropriate to their nature. Collections of pus in the nasal sinuses may demand trephining and antiseptic injections. Swellings about the throat threatening asphyxia and which cannot be relieved by evacuation of pus may necessitate tracheotomy until suppuration occurs. The cutaneous pustules and abscesses are dealt with by pricking the collections and washing daily or oftener with astringent antiseptics (phenic acid and alum). Bronchitis and broncho-pneumonia may be benefited by sinapisms applied to the sides of the chest, the internal administration of potassium iodide, ammonium chloride, sodium hyposulphite, terpene or terpinol; or by inhalation of weak sulphur fumes, or tar vapor.

For abscesses in the bronchial or mesenteric glands, the brain, spinal cord, or other internal organ, little can usually be done but to sustain the patient and await the course of events. If the abscess can be accurately located it may be aspirated and then injected with an antiseptic; if in the encephalon, trephining may be resorted to; death is certain in such a case in the absence of treatment.

During convalescence it is very important to avoid overexertion and chill, which are very liable to bring on petechial fever. Also, to feed nourishing food, give pure air and water, and to see that no suspension of action of bowels, or kidneys threatens to shut up toxins and waste products in the system. Apropos of impure water Williams quotes the case of a foul stream near Bradford, England, on the banks of which every case of strangles did badly.