Part 10

The inveterate cases may usually be subdued and rendered controllable for a time by one of the methods of subjugation employed by the professional tamers, but unless they are thereafter kept in good hands they are liable to relapse into the old habit. Among the more effective methods are the Rarey mode of throwing which may be repeated again and again until the animal is thoroughly impressed with a sense of the domination of man and the futility of resistance; the resort of tying the head and tail closely together and letting the animal weary and daze himself by turning in a circle, first to the one side and then to the other; the application of the Comanche bridle made of a small rope, one loop of which is passed through the mouth and back of the ears and drawn tightly, then another loop is made to encircle the lower jaw, and the chin is drawn in against the trachea by passing the free end of the rope round the upper part of the neck and again through the loop encircling the lower jaw and drawing it tight; or a similar small rope is passed a number of times through the mouth and back of the ears and drawn tightly so as to compress the medulla and stupify the animal. This is supposed to be rendered more effective by passing one turn each between the upper lip and gums and between the lower lip and the gums.

CATALEPSY.

Definition. Tetanic and paralytic forms. Balance of flexors and extensors Cataleptoid. No constant lesion. Hysterical. Hypnotic. Subjects: horse, ox, wolf, cat, chicken, Guineapig, snake, frog, crayfish. Causes: strong mental impression, indigestion, etc., in susceptible system. Lesion: inconstant, muscular degeneration, etc. Symptoms: wax-like retention of position given, voluntary movement in abeyance, mental functions impaired, secretions altered. Duration and frequency variable. Treatment: shock; cold; ammonia, pepper, snuff, electricity, amyle nitrite, nitro-glycerine, apomorphine, bromides, purgatives, bitters, iron, zinc, silver, open air exercise.

Definition. This is a functional nervous disorder, characterized by paroxysms of impaired or perverted consciousness, diminished sensibility, and above all a condition of muscular rigidity, by means of which the whole body, or it may be but one or more limbs retain any position in which they may be placed.

Laycock describes two forms in man—the catochus or tetanic form, and the paralytic form. Mills would restrict the name catalepsy to cases in which the muscular tone is such that the affected part may be bent or moulded like wax or a leaden pipe, and will not vary from this when left alone. Other forms in which this waxen flexibility (flexibilitas cerea) is absent or imperfect he would designate as cataleptoid.

The disease is not associated with any constant cerebral lesion, though it may supervene in the course of other nervous disorders, and therefore may own an exciting cause in existing lesions of the brain. The immediate cause must however be held to be functional, and this is in keeping with its most common form in man (hysterical), and with the hypnotic form which is observed both in man and animals. This latter may be looked on as a form of induced or hypnotic sleep, in which the retention of the position given to a limb or part is the most prominent symptom. In all cases there is an impaired condition of the sensory functions of the cerebral convolutions, and an insusceptibility of the motor centres to the control of the will, or the reflex stimulus.

Hering has recorded the disease in the horse, Landel in the ox, and Leisering in the prairie wolf. The hypnotic form has been shown in cats, chickens, and Guinea pigs. The serpent charming of the Indian dervishes and similar effects on frogs and crayfish have been attributed to hypnotic catalepsy.

Causes. Strong mental emotions and diseases which profoundly affect the nervous system have been adduced as causes (fear, excitement, chills). Indigestible food has even been charged with causing it. There is undoubtedly, to begin with, a specially susceptible nervous system, and hence it is liable to prove hereditary, and in man to appear as a form of hysteria, or to alternate in the same family with epilepsy, chorea, alcoholism, opium addiction and other neurosis.

Hypnotism as a cause is claimed by various writers. Azam says that in the fairs in the South of France, jugglers hypnotize cocks by placing the bill on a board, on which they trace a black line passing between the two feet of the bird. Cadeac adds that Father Kircher, in the 17th century, employed a similar method to put fowls to sleep. Alix put cats to sleep by securing them firmly, and then looking steadily into their eyes. The condition attained varies according to the degree of the sleep, the will being dominated first, and later, consciousness of external objects is lost. Hypnotism, however, appears to be difficult and uncertain in the lower animals, in keeping with the limited development of intelligence and will, as compared with the human being. Cadeac states that the very old and the very young are completely refractory to hypnotizing influences.

Lesions. No constant pathological changes are found, though different nervous lesions may serve to rouse the disease in a predisposed subject. Fröhner found in the affected muscles granular swelling, fatty degeneration, hæmorrhages, and waxy (amyloid) degeneration of the cardiac muscles, corresponding to what has been found in tetanus; also hæmorrhages on the stomach and intestines.

Symptoms. The leading objective symptom is the tonic condition of the muscles by which a perfect balance is established and maintained between the flexors and extensors so that the affected part maintains the same position which it had when the attack began, or any other position which may be given to it during the progress of the paroxysm. The position is only changed when the muscles involved have become completely exhausted. During the attack the affected muscles are swollen and firm, so that their outline may often be traced through the skin, later as the attack subsides they become soft and flaccid. Voluntary movement of the affected muscles is impossible until after the paroxysm. The attack usually comes on suddenly and in this respect resembles epilepsy; at other times there are premonitory symptoms of nervous anxiety, excitement or irritability. There is usually considerable impairment of consciousness, intelligence, common sensation, and even of the special senses. In a cataleptic dog Fröhner noted mental and motor troubles, considerable anæsthesia, and loss of sight, smell, and hearing. The eyes are fixed, the pupils either contracted or dilated, and the urine passed may be albuminous or even icteric.

Course, Duration. Like other functional nervous disorders this is extremely uncertain in its progress. There may be but one attack or a succession; they may last from a few minutes, to 7 days (Fröhner), or even several weeks (Hertwig); they may end in recovery or less frequently they may prove fatal usually by inanition.

Treatment. During a seizure a sudden shock will sometimes cut short the attack, douching with cold water, an inhalation of ammonia, of capsicum or of snuff, or the application of electricity in an interrupted current through the spine and affected muscles. Ether anæsthesia will not always relax (Sinkler). Inhalation of a few drops of nitrite of amyle has proved effective in man, as has also the injection subcutem of three drops of a 1 per cent solution of nitro-glycerine, apomorphine hypodermically is usually effective (Sinkler). Bromide of potassium has also been advised, and in case of coldness of the surface, a warm bath.

When there is overloaded stomach and gastric indigestion an emetic is indicated, and in constipation a purgative (for speedy action chloride of barium or physostigma subcutem).

In the intervals between attacks tonics and general hygiene should be invoked to build up the weakened nervous system. Quinine, and salts of iron, zinc or silver with a nourishing diet and out door exercise are especially indicated.

INSOLATION. HEAT EXHAUSTION. SUNSTROKE. THERMIC FEVER.

Definition: two forms. =Heat exhaustion.= Causes: prolonged heat, and moisture, overexertion. Impaired vaso-motor centre. Failing heart. Carbon dioxide poisoning. Symptoms: weak, fluttering pulse, perspiration, muscles flaccid, prostration, no hyperthermia. Treatment: stimulant, digitalis, digitalin, subcutem, nitro-glycerine, warm baths. =Thermic fever.= Hyperthermia excessive. Causes: insolation, prolonged heat and impure air, furnace heat, moist and dry heat, electric tension, overwork, muscular exhaustion, coagulation of myosin, constant heat on one part (head), excess of carbon dioxide, stiffening of bodies when killed in hot weather, debility, weakness, fatigue, chest constriction, tight girths or collars, short bearing reins, plethora, obesity, open cars and yards, fever, privation of water, heavy fleece. Lesions: right heart and systemic veins full, blood black fluid or diffluent, left ventricle empty, congested meninges, effusions in or on brain, or hæmorrhages. Symptoms: =horse=: dull, stupid, stubs toes, sways quarters, droops head, hangs on bit, props on feet, breathes rapidly, pants, stertor, dilated nostrils, gasping, fixed eyes, dilated pupils, tumultuous heartbeats, gorged veins, epistaxis, perspiration, convulsions: =ox=: parallel symptoms: =sheep=: open mouth, stertor, fixed eyes, pupils dilated, panting, swaying, fall, convulsions: =dog=: dull, prostrate, pants, congested veins and mucosæ, weakness, spasms, syncope, speedy rigor mortis. Overheating. Diagnosis: early excessive hyperthermia, venous congestion, shallow panting breathing, violent heart action, loss of sensory and motor functions, convulsions. Prevention: avoid violent, prolonged heat, and exertion, especially in case of fat animals or those new to hot climate, keep emunctories acting, shade head, water on head and to drink, protect fat cattle, shear sheep, water. Treatment: shade and laxatives; if severe, cold water from hose, ice bags to poll, rub legs, acetanilid subcutem, stimulant enemata, later mineral tonics, iron or zinc.

Definition. A morbid condition produced by the exposure to extreme heat, and marked by profound disorder of the vaso-motor and heat centres.

The single term of sun-stroke or heat-stroke has been replaced by two,—=heat exhaustion= and =sun-stroke=, indicating two distinct conditions, brought about by exposure to heat and manifested by different states of the body and distinctive symptoms.

Heat Exhaustion.

This appears as an exaggerated form of the general sense of relaxation, weakness and languor which follows on prolonged violent exertion in a hot atmosphere. There is more or less impairment of the vaso-motor nerve centre in the medulla, relaxation of the capillary system, and flagging of the heart’s action, which loses its customary stimulus, by reason of the defective supply of blood returned by the veins. This may become so extreme that the patient dies by syncope. In other cases the paresis is mainly shown in the vaso-motor system, and its centres in the medulla, the blood is delayed in the distended capillaries and veins, it becomes overcharged with carbon dioxide, the heart’s action is accelerated and feeble, the pulse rapid, weak and fluttering, perspiration breaks out on the skin, and the temperature is normal or subnormal. The muscular weakness, the flaccid condition of the facial muscles, and general depression suggest a state of collapse. This condition is not necessarily due to exposure to the intensity of the sun’s rays, but may come on in animals subjected for a length of time to artificial heat, and especially if the air is impure, and if the subject has to undergo severe physical exertion.

Treatment. In slight cases of this kind a stimulant is usually desirable and ammonium carbonate in bolus or solution will usually serve a good purpose. In its absence alcohol or spirits of nitrous ether may be given. Digitalis is of great value in sustaining the flagging action of the heart and has the advantage that as digitalin it can be given hypodermically when it is impossible to give ammonia, alcohol or ether by the mouth. For the same reason nitro-glycerine may be resorted to, or even atropia as a vaso-motor stimulant. Active friction of the body and limbs will aid circulation and indirectly stimulate the heart, and in case of subnormal temperature it may be supplemented by a warm bath in the smaller animals, kept up until the normal temperature in the rectum has been restored.

Thermic Fever. Sun-stroke.

This is readily distinguished from heat exhaustion by the predominance of the hyperthermia. While in =heat exhaustion= the temperature is usually subnormal, in =sun-stroke= it is excessive, (108°–113° F.).

Causes. The immediate cause of sun-stroke is exposure to undue heat, but this need not be the heat of the sun’s rays direct. A large proportion of cases in the human subject are attacked during the night, and again at sea where an attack in a passenger is practically unknown, it is terribly common among stokers working in a close atmosphere of 100° to 150° F.

The attendant conditions have much influence in determining an attack, thus it is generally held that heat with excess of moisture is the most injurious, yet in Cincinnati, statistics showed a greater number of cases in man when the air was dry. The suppression of perspiration and the arrest of cooling by evaporation in the latter case would tend to a rapid increase of the body temperature, and the condition would be aggravated by the electric tension usually present with the dry air. With the hot, moist air perspiration might continue, but evaporation would be hindered, and there would be arrest of the cooling process and an extreme relaxation of the system.

Again, if is usually found that seizures take place during or after hard muscular exertion in a hot period, and much importance is attached to the attendant exhaustion, the excess of muscular waste, and the alteration of the myosin, which latter coagulates at a lower temperature in the overworked animal. But on the other hand, experiment shows that the animal confined to absolute inactivity in the hot sunshine or in a high temperature (at 90°), dies in a few hours, whereas another animal left at liberty in the same temperature does not suffer materially. The explanation appears to be that the dog, kept absolutely still, has the continuous action of the heat on the same parts and on the same blood, for the capillaries dilate, and the blood is delayed, overheated, and surcharged with carbon dioxide, and the result is either syncope from heart failure, or asphyxia from excessive carbonization of the blood. Back of these and concurring with them is the paralysis of the vaso-motor and heat generating nerve centres, from the high temperature or the condition of the blood.

The excessive carbonization of the blood deserves another word. The prolonged contact of the blood and air in the lungs is essential to the free interchange of oxygen and carbon dioxide. Vierordt showed that with sixty respirations per minute the expired air became charged with but 2.4 per cent. of this gas, whereas with fourteen respirations it contained 4.34 per cent. Therefore, with violent muscular work (which charges the blood with carbon dioxide) and rapid breathing (which fails to secure its elimination), the overdriven animal soon perishes from asphyxia. Under a high temperature of the external air, this condition is aggravated since the rarefied air contains just so much the less oxygen, the absorption of which is the measure of the exhalation of carbon dioxide.