Treatment. The prophylactics and therapeutics of vertigo will vary with the cause. The diagnosis of the cause is therefore the most important step. In pampered, overfed, idle horses a reduced ration and daily exercise or work will often suffice. It is usually desirable, however, to remove intestinal irritants and deplete the vascular system by an active purgative. If the attacks appear only in Spring this care should be especially given at such seasons. A tight or badly fitting collar should be corrected, also a position of the breast strap which causes it to press on the jugular veins. A short bearing rein causing undue flexion of the head must be lengthened or abandoned. A too dark stable should be avoided, also the sudden exposure to white, dusty roads and, still more so, to the glare of snow, ice, or water. A short, overdraw check rein, turning the eyes up directly into the sun’s rays, or blinds with a glistening inner surface may require correction. It may be better to abandon blinds altogether, or to cover the eyes by a piece of leather, 2 to 4 inches wide, extending across the forehead from one eye to the other; or a sunshade attached to the headstall may be worn so as to protect the eyes. Horses which become seasick or carsick may sometimes be helped by covering the eyes. Other indications would be to treat any existing trouble which interferes with a normal circulation in the brain (pulmonary congestion, aneurisms, tumors pressing on carotids or jugulars, phlebitis, etc.), and such as affect the ear (disease of the pharynx, guttural pouches, adjacent glands, petrous temporal bone, membrana tympani, external ear). Indurated wax, insects or insect larvæ may be removed by careful irrigation with warm water, and perhaps by chloroform. Nasal parasites must be washed out or destroyed by benzine, and any hyperæsthesia of the nasal mucosa may be met by covering the nostril with a net, or radically by cutting the facial branch of the 5th nerve as it emerges from the infra-orbital foramen.
When attacked the horse should be at once stopped and put under the shadow of a roof or tree, or in their absence a blanket or lap robe may be used to cover his eyes. If there is danger of falling remove the harness, and secure a soft piece of ground, free from stones or other hard bodies. Cold water applied to the head will sometimes check. A common practice is to bleed from the palate, and in plethoric cases especially, and in such as are dependent on congestion, tumors or other lesion of the brain it is to be commended. The action will be rendered more prompt and effective if the blood is taken from the jugular. A laxative diet, and carefully regulated work are desirable to obviate the tendency to the affection, and this may often be accomplished by a run at pasture. Otherwise daily small doses of Glauber salts in the feed may suffice. Bromides may be used to calm nervous excitement.
In cases of gastric vertigo an active cathartic, followed by smaller laxative doses or a laxative diet and a course of bitters may prove useful. Such cases should never be worked on a full stomach but should be left at rest for at least an hour after a meal.
In aural vertigo special attention must be given to the throat, and external ear. Bromides may often be useful, and sometimes benefit may be derived from an occasional blister or light firing back of the ear.
In cœnurus cerebralis in sheep the only resort is to trephine and remove the parasite.
CONCUSSION OF THE BRAIN.
Definition. Causes: leaps, trips, falls, blows. Symptoms: fall, insensibility, flaccidity, suspended respiration, tumors, vomiting, recovery, signs of cerebral congestion. Pathology: anæmia followed by congestion. Diagnosis: from fracture, epilepsy. Treatment: quiet, rubbing of limbs, ammonia, cold to head, or heat; for congestion, bromides, depletion, ice pack, derivatives.
Definition. Concussion is the condition produced by mechanical jar or shock of the cerebral mass, and manifested by modification of the brain functions of any grade from a simple dazed condition to that of complete unconsciousness.
Causes. The most familiar cause is the stroke of the butcher’s pole axe, producing sudden and absolute insensibility. A horse in leaping, trips and falls on his head or running against a wall sustains a concussion, which leaves him for some seconds without any signs of life. The same will happen to other animals, but above all to rams which in their combats, back for a number of yards and running together meet with a shock from the effect of which even their thick skulls cannot save them. Other blows upon the head operate to the same end.
Symptoms. Concussion is manifested by different grades of symptoms. At first there is usually a fall with complete insensibility. The animal lies flaccid, utterly insensible to external irritation and there is suspension of respiration. The heart continues to beat and a frequent weak pulse may be often detected. In slight cases, breathing may be reestablished at the end of a minute or two, with muscular tremors and movements of the limbs; then the animal rises, shakes his head, neighs, and walks at first unsteadily and afterward with greater and greater firmness. In vomiting animals, emesis occurs.