The principal lines of treatment are preventive measures and careful nursing. This is one of the diseases that can be largely prevented by observing all possible sanitary precautions in caring for animals. It is admitted by writers that the greater majority of cases of inflammation of the brain and its coverings are caused by infection. Proper stable construction, ventilation and disposal of the manure, an occasional disinfection of the stable, cleaning and disinfecting the drinking places and water tanks, and the necessary attention to the ration greatly reduce the loss from this disease.
The animal should be gotten into a dark, quiet, roomy stall that is well bedded. A swing may be placed under a large animal if it is able to support any of its weight, and there is no evidence of nervous excitement. We should do nothing to disturb it. If possible, the position of the animal that is unable to get up should be changed, and the bed kept clean and dry. Cold in the form of wet or ice packs should be applied to the head during the acute stage. Symptoms of excitement must be overcome by large doses of sedatives. Iodide of potassium and strychnine may help in overcoming the paralysis. The bowels should be emptied by giving an occasional physic. A very light, easily digested diet should be fed.
PARTIAL OR COMPLETE PARALYSIS OF THE POSTERIOR PORTION OF THE BODY.—This disorder is especially common in the small animals. The hog is most frequently affected.
The following causes may be mentioned: Inflammation of the spinal cord commonly occurs in influenza, strangles and mixed infections; constipation brought on by improper feeding and insufficient exercise is a predisposing cause; injuries such as strains and blows in the region of the back may also cause it; compression of the spinal cord by the vertebrae is no doubt a very common cause; dislocation, enlargement of the disks between the vertebrae, bony enlargements resulting from strains and injuries, rickets, tuberculosis and actinomycosis and tumors commonly cause compression of the cord. It is rarely caused by parasites. Young, fat animals are especially prone to injuries in the region of the back. Such animals may suffer from malnutrition of the bones, and complete fractures of the thigh bones may occur. Extreme heat from the sun's rays and close, hot quarters are probable causes.
The symptom that is most prominent is the partial or complete loss of control over the movements of the hind parts. The appetite may be little interfered with. The animal may sit on the haunches, with the limbs projecting forward, or swing the hind quarters from side to side in walking or trotting. Irregularity in the animal's movements is especially noticeable when turning or backing. In case the animal suffers pain, the spine is held rigid or arched, and when forced to move, marked evidence of pain occurs. There may be a decrease or increase in the sensibility of the part. The increase in sensibility is noticed on striking the muscles with the hand or rubbing the hair the wrong way. Spasmodic twitching or contractions in the muscles sometimes occur. There is frequent elevation of temperature. The animal is unable to pass urine or faeces, or there may be an involuntary passage of the body excretions.
The outcome of this disease is unfavorable. Acute inflammation of the covering of the cord may subside within a few days. Cases that do not recover within a few weeks should be destroyed. Paralysis of the hind parts should not be confused with rheumatism, azoturia and other disorders that may interfere with the movements of the posterior portion of the body.
The treatment is largely along preventive lines. A predisposition toward rickets, and injuries, may be prevented by feeding a proper ration, and permitting the animal to take exercise. The quarters and the attendant are frequently responsible for injuries. If this is the case, the rough handling of the animals should be immediately corrected, and any condition of the quarters that favors the crowding or piling up of animals should be changed. Large animals may be placed in swings if they are able to support a part of their weight on the hind limbs. This is especially indicated at the very beginning of the disorder. Small animals should be given a good bed. A very light, easily digested ration should be fed. An occasional physic should be administered. Strychnine and iodide of potassium may be given. Cold applications to the back are indicated.
QUESTIONS
1. What organs comprise the central portion of the nervous system? Peripheral portion?
2. Give a general description of the brain.