rather frequent syndrome. A hyperemia that on autopsy proves to be well-marked may have been associated with very slight disturbances of consciousness. On the other hand, a slight hyperemia such as one may find on posting a bovine that has died of malignant head catarrh, may have been associated with a paralysis and loss of consciousness that finally become complete. Hyperemia alone does not cause a fever. Possibly attacks of abdominal vertigo" ("stomach staggers ") depend on circulatory disturbances in the meninges. Circulatory changes occurring in the central nervous system as a partial condition in the terminal stages of any fatal diseases may cause symptoms of deranged consciousness, motor irritation, and paralysis.

INTOXICATIONS

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In addition to the specific forage poisoning known as botulism it is possible that other similar intoxications exist. In certain parts of the Eastern United States cases of apparent intoxication affecting to some extent the central nervous system are common in the fall and spring. These show normal temperature, anorexia, icteric mucosae, respiration and pulse normal, general paresis, slight clonic spasms of many of the skeletal muscles, and a paralysis of the facial or some other cranial nerve. Following a laxative a horse may recover in less than a week.

INTOXICATION - EQUINES

In other cases the horse appears normal to the owner, and is found lying flat and unable to rise an hour later. In this case the penis may be paralyzed and hanging out of the prepuce; the next patient may be paretic for 12 to 24 hours before falling and fail to show paralysis of any particular peripheral nerve. Horses that go down usually die in about a week. They may be able to chew and swallow food, though constipation is present. The sensorium appears bright.

In one of the more severe forms of this type presenting a normal consciousness, normal temperature, congested mucosae, slight orthotonus, inability to rise, fair appetite and normal passage of urine and feces, the autopsy findings after slaughter by bleeding were as follows: serosanguineous exudate in the abdominal cavity and pericardial sac. Cerebro-spinal fluid contains a hemorrhagic fibrinous exudate. Cortex of the cerebrum and cerebellum are covered with hemorrhages. The spinal fluid has a deep cherry color. Dr. Goldberg reports that on histological section of the brain substance no lesions are found. This may be properly termed a cerebrospinal meningitis.

INTOXICATION - COWS

A mild and transient form in cows may manifest motor irritation (plunging forward in the stanchion, frequent urination, nervous switching of the tail) and an irritative disturbance of consciousness (excitement).

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After a laxative the condition may soon return to normal. more severe forms orthotonus is present at the onset and may persist for days, paresis develops, the gait becomes uncertain, anu there may be a weaving of the head. There are either no febrile symptoms, or a slight rise of the pulse, respiration and temperature. Recovery may be only partial. In others there is a slight degree of excitement. Neurai paralysis may cause blindness and sinking of one eye, or paralysis of the pharynx.

To judge from the symptoms the chief lesions do not appear to be cerebral. A moderate amount of hyperemia is sufficient to account for the disturbance of consciousness, as well as the milder forms of motor irritation. Paresthesia is occasionally observed. It is manifested by constant rubbing of the buttocks against the wall and violent licking of the fetlock region. That bacterial intoxication may induce this series of symptoms is proven by observations in cases of acute metritis wherein a thorough uterine douche has led to prompt recovery. For want of more complete information those cases associated with indigestion, or occurring together at a season when acute digestive affections are frequent, are termed food intoxication.

The more severe types of this group die. As in horses, after they are once down and flatly recumbent on the side, recovery has not occurred. The course is from three days to a week, even ten days. Autopsy shows a serosanguineous fluid beneath the meninges.

Parturient paresis in cows presents the characteristic symptoms of an intoxication: absence of fever; deranged consciousness (excitement followed by depression and loss of consciousness); motor irritation (slight clonic spasms to convulsions at the onset); and finally paralysis.

ACUTE MENINGO-ENCEPHALITIS

When of umbilical origin in the new-born, this may show tetanic contractions (orthotonus), and a high degree of motor irritation (convulsions). Lambs may live for two weeks and then gradually lose control of the hind legs, lie on the side unable to rise, paddle with the limbs, eat and appear to show a normal consciousness. Autopsy shows a purulent inflammation of the meninges of the cord and cerebellum.

Pyemic purulent meningitis sometimes follows docking and castration of lambs. They show depression and lateral recumbency (paralysis). Motor irritation is marked: trembling, orthotonus, contraction of the extensor muscles of the legs and back, convulsions induced by handling, contracture of the fetlock joint, causing the animal to walk on the toes, rotation of the eyeballs. Others show paralysis of the extremities (dangling of one front leg below the carpus).

When meningo-encephalitis in cows is well marked it may be ushered in with convulsions. In two or three days attacks become more frequent, until at the end of a week or ten days general

tetanic contractions exist for hours at a time. Apparently such conditions may be the result of a traumatic gastritis.

Purulent meningitis affecting the cerebrum occurs in cows as a pyemic complication of septic metritis, and in some cases there is no external evidence of the metritis. The symptoms are marked dullness; various degrees of motor irritation (unilateral contraction of the cervical muscles, orthotonus, clonic spasms); paralysis affecting certain cranial nerves (one ear dropped, ptosis of an eye-lid); finally paralysis.

Cerebral

ENCEPHALITIS

Tuberculous encephalitis in bovines may present marked cerebral excitement, even mania, the attitude being similar to that of rabies. Tetanic contractions (orthotonus) are not infrequent. Finally, paralysis supervenes and becomes complete. All the symptoms are marked.

Cerebellar.- Degenerations cause symptoms that vary in intensity and kind according to the degree of injury. Motor irritation may be observed at first in the form of slight stiffness of the muscles of the neck and legs. The pulse, respiration and temperature usually remain normal. Finally tetanic contractions develop (orthotonus), the animal lies in an unnatural position, and is unable to rise. The condition may then improve for a few days. Consciousness and sensation remain normal. As the lesion progresses motor irritation becomes still more marked, even to the extent of rotation backwards around the transverse axis. On turning the head quickly to one side or the other the animal may fall and appear in distress.

EPILEPTIFORM ATTACKS

Etiology unknown. Characterized by convulsions and loss of consciousness. Possibly these are due to cholesteatoma. The attacks are brought on by hard work. One case has been reported in a cow.

TUMORS

Cholesteatomas in the horse cause a variety of symptoms. Usually the case is diagnosed as "dummies. The animal may show alternating periods of excitement and dullness, does not respond to the bit and drives entirely on the line. The course may be prolonged and develop the characteristic symptoms of "dummies or an epileptiform attack with excitement and mania may terminate in sudden death.

SPINAL PARALYSIS

This often occurs in animals a few weeks old from abscess formation in the region of the vertebrae.

At first the hind legs seem weak or stiff. Shortly there is inability to raise the hind parts; in recumbency the hind legs are

stretched away from the body where they remain in an extended flaccid condition. The sensorium is normal. In cows it is to be differentiated from paraplegia, after parturition and slipping, due to subluxation of the hip joints.

POISONING

Lead.- Motor irritation is manifested by circling in one direction and pressing the head against objects. Blindness develops early in calves. Tetanic contractions may occur, followed by convulsions and bellowing. The outstanding symptoms reflect brain lesions and autopsy shows marked hyperemia of the meninges, choroid plexus and ventricles.

The foregoing discussion on the interpretation of nervous symptoms in domestic animals lacks much in completeness and accuracy. Veterinary literature is wanting in a harmonious description of symptomatology and pathology of affections of the central nervous system. The average clinician has little opportunity to obtain information on the pathological lesions of his patients, and the research investigator seems to have taken little or no interest in recording the symptomatology of his subjects. The described symptoms are taken from patients treated in the ambulatory clinic, and where it has been possible to follow them up and obtain an autopsy the evidence is conclusive. One is impressed by the degree of inflammation that may occur in the meninges of animals without causing a corresponding disturbance of, the consciousness.

The dividing line between the affections of the central nervous system is not definite, and in cases that do not come to autopsy a positive diagnosis is often difficult.

SURGICAL DISEASES OF THE UDDER

J. N. FROST

Department of Surgery

Cow-Pox

This is a common disease of dairy cattle but the organism causing it is unknown. The pustular stage is often overlooked by the herdsman and not much attention is paid to the disease until the pustules have ruptured and a dry scab formed. Several pustules which may have formed close together may rupture at one time, forming a large sized scab.

Frequently mastitis develops as a result of cow-pox, either by metastasis or up the teat canal, with a cow-pox or secondary organism which may be present in this disease.

In preventing the spread of this disease the cow should be milked by a separate milker or else milked last. The hands of the milker should be washed before and after milking each animal and the stall of each thoroughly disinfected.

In treating the disease the scabs are removed and the pits treated with equal parts of tincture of iodine and glycerine.

There are a number of diseases similar to cow-pox which cause trouble with the udder. One of these which has been quite common in our locality is caused by a streptococcus and affects the skin of the udder but not the teats.

It spreads rapidly through the herd and while it produces mastitis in only a small per cent of cases, it does cause a very sore udder. It appears first as a moist area on the skin from one to two inches in diameter. Later the skin becomes dry and necrotic and sloughs with a core leaving a deep pit which heals slowly.

In treating we have had good results by swabbing the wound with tincture of iodine and using an autogenous bacterin on the whole herd.

DERMATITIS

When the udder of the cow is exposed to cold and moisture the skin frequently becomes inflamed and fissured. Wet milking, particularly in the winter, may produce the same condition.

Dermatitis is also produced in the fresh cow by the enlarged and inflamed udder rubbing against the thigh or coming in contact with a damp, cold floor. When the teats become fissured as a result of dermatitis, milking causes bleeding and considerable pain to the cow so that she may be made a kicker.

Hownot contain water. equal parts of zinc enough tincture of

Dermatitis usually responds to the use of antiseptics. ever, it is better to use antiseptics which do The antiseptic we have found most useful is oxide and glycerine, sometimes adding just iodine to give it a little color.