of small, black nodules in gray horses, and in one instance are believed
to have induced the condition known as stringhalt.
Fibrous tumors may develop within or from the meningeal structures of
the brain.
Gliomatous tumor is a variety of sarcoma very rarely found in the
structure of the cerebellum.
Treatment for tumors of the brain is impossible.
SPASMS, OR CRAMPS.
Spasm is a marked symptom in many diseases of the brain and of the
spinal cord. Spasms may result from irritation of the motor nerves as
conductors, or may result from irritation of any part of the sympathetic
nervous system, and they usually indicate an excessive action of the
reflex motor centers. Spasms may be induced by various medicinal agents
given in poisonous doses, or by effete materials in the circulation,
such as nux vomica or its alkaloid strychnia, lead preparations, or an
excess of the urea products in the circulation, etc. Spasms may be
divided into two classes: Tonic spasm, when the cramp is continuous or
results in persistent rigidity, as in tetanus; clonic spasm, when the
cramping is of short duration, or is alternated with relaxations. Spasms
may affect involuntary as well as the voluntary muscles, the muscles of
the glottis, intestines, and even the heart. They are always sudden in
their development.
_Spasm of the glottis._--This is manifested by a strangling respiration;
a wheezing noise is produced in the act of inspiration; extreme anxiety
and suffering for want of air. The head is extended, the body profusely
perspiring; pulse very rapid; soon great exhaustion becomes manifest;
the mucous membranes become turgid and very dark colored, and the animal
thus may suffocate in a short time.
_Spasm of the intestines._--(See "Cramp colic," p. 74.)
_Spasm of the neck of the bladder._--This may be due to spinal
irritation or a reflex from intestinal irritation, and is manifested by
frequent but ineffectual attempts to urinate.
_Spasm of the diaphragm, or thumps._--Spasmodic contraction of the
diaphragm, the principal muscle used in respiration, is generally
occasioned by extreme and prolonged speeding on the race track or road.
The severe strain thus put upon this muscle finally induces irritation
of the nerves controlling it, and the contractions become very forcible
and violent, giving the jerking character known among horsemen as
"thumps." This condition may be distinguished from violent beating of
the heart by feeling the pulse beat at the angle of the jaw, and at the
same time watching the jerking movement of the body, when it will be
discovered that the two bear no relation to each other. (See
"Palpitation of the heart," p. 259.)
_Spasm of the thigh, or cramp of a hind limb._--This is frequently
witnessed in horses that stand on sloping plank floors--generally in
cold weather--or it may come on soon after severe exercise. It is
probably due to an irritation of the nerves of the thigh. In cramps of
the hind leg the limb becomes perfectly rigid, and attempts to flex are
unsuccessful; the animal stands on the affected limb, but is unable to
move it; it is unnaturally cold; it does not, however, appear to cause
much suffering unless attempts are made to change position. This cramp
may be of short duration--a few minutes--or it may persist for several
days. This condition is often taken for a dislocation of the stifle
joint. In the latter the foot is extended backward, and the horse is
unable to advance it, but drags the limb. An examination of the joint
also reveals a change in form. Spasms may affect the eyelids, by closure
or by retraction. Spasm of the sterno-maxillaris muscle has been
witnessed, and the animal was unable to close the jaws until the muscle
became relaxed.
_Treatment of spasms._--An anodyne liniment, composed of chloroform 1
part and soap liniment 4 parts, applied to cramped muscles will usually
cause relaxation. This may be used when single external muscles are
affected. In spasms of the glottis, inhalation of sulphuric ether will
give quick relief. In spasm of the diaphragm, rest and the
administration of half an ounce of chloroform in 3 ounces of whisky,
with a pint of water added, will generally suffice to bring relief, or
if this fails give 5 grains of sulphate of morphia by hypodermic
injection. If spasms result from organic disease of the nervous system,
the latter should receive such treatment as its character demands. In
cramp of the leg, compulsory movement usually causes relaxation very
quickly; therefore the animal should be led out of the stable and be
forced to run or trot. Sudden, nervous excitement caused by a crack of
the whip or smart blow will often bring about immediate relief. Should
this fail, the anodyne liniment may be used along the inside of the
thigh, and chloroform, ether, or laudanum given internally. An ounce of
the chloral hydrate will certainly relieve the spasm when given
internally, but the cramp may return soon after the effect has passed
off, which in many cases it does very quickly.
_Convulsions._--Although there is no disease of the nervous system which
can be properly termed convulsive, or justify the use of the word
convulsion to indicate any particular disease, yet it is often such a
prominent symptom that a few words may not be out of place. General,
irregular muscular contractions of various parts of the body, with
unconsciousness, characterize what we regard as convulsions, and like
ordinary spasms are dependent upon some disease or irritation of the
nervous structures, chiefly of the brain. No treatment is required; in
fact, a general convulsion must necessarily be self-limited in its
duration. Suspending, as it does, respiratory movements, checking the
oxygenation and decarbonization of the blood, the rapid accumulation of
carbonic-acid gas in the blood and the exclusion of oxygen quickly puts
the blood in a condition to produce the most reliable and speedy
sedative effect upon the nerve excitability that could be found, and
consequently furnishes its own remedy so far as the continuance of the
convulsive paroxysm is concerned. Whatever treatment is instituted must
be directed toward a removal of the cause of the convulsive paroxysm.
CHOREA, OR ST. VITUS'S DANCE.
Chorea is characterized by involuntary contractions of voluntary
muscles. This disease is an obscure disorder, which may be from pressure
upon a nerve, cerebral or spinal sclerosis, small aneurisms in the
brain, etc. Choreic symptoms have been produced by injecting granules of
starch into the arteries entering the brain. Epilepsy and other forms of
convulsions simulate chorea in appearance.
Stringhalt is by some termed "chorea." This is manifested by a sudden
jerking up of one or both hind legs when the animal is walking. This
symptom may be very slight in some horses, but has a tendency to
increase with age. In some the catching up of the affected leg is very
violent, and when it is lowered to the ground the motion is equally
sudden and forcible, striking the foot to the ground like a pile driver.
Very rarely chorea may be found to affect one of the fore legs, or the
muscles of one side of the neck or the upper part of the neck.
Involuntary jerking of the muscles of the hip or thigh is seen
occasionally, and is termed "shivering" by horsemen.
Chorea is often associated with a nervous disposition, and is not so
frequent in animals with a sluggish temperament. The involuntary
muscular contractions cause no pain, and do not appear to produce much
exhaustion of the affected muscles, although the jerking may be regular
and persistent whenever the animal is in motion.
_Treatment._--In a few cases, early in the appearance of this affection,
general nerve tonics may be of benefit, viz, iodid of iron, 1 dram;
pulverized nux vomica, 1 dram; pulverized scutellaria (skull-cap), 1
ounce. Mix and give in the feed once a day for two weeks. Arsenic in the
form of Fowler's solution is often beneficial. If the cause is connected
with organic brain lesions, treatment is usually unsuccessful.
EPILEPSY, OR FALLING FITS.
The cause of epilepsy is seldom traceable to any special brain lesions.
In a few cases it accompanies disease of the pituitary body, which is
located in the under surface of the brain. Softening of the brain may
give rise to this affection. Attacks may occur only once or twice a year
or they may be of frequent recurrence.
_Symptoms._--No premonitory symptoms precede an epileptic fit. The
animal suddenly staggers; the muscles become cramped; the jaws may be
spasmodically opened and closed, and the tongue become lacerated between
the teeth; the animal foams at the mouth and falls in a spasm. The urine
flows involuntarily, and the breathing may be temporarily arrested. The
paroxysm soon passes off, and the animal gets on its feet in a few
minutes after the return of consciousness.
_Treatment._--Dashing cold water on the head during the paroxysm. After
the recovery 1 dram of oxid of zinc may be given in the feed twice a day
for several weeks, or benefit may be derived from the tonic prescribed
for chorea.
PARALYSIS, OR PALSY.
Paralysis is a weakness or cessation of the muscular contraction by
diminution of loss of the conducting power or stimulation of the motor
nerves. Paralytic affections are of two kinds, the complete and the
incomplete. The former includes those in which both motion and
sensibility are affected; the latter those in which only one or the
other is lost or diminished. Paralysis may be general or partial. The
latter is divided into hemiplegia and paraplegia. When only a small
portion of the body is affected, as the face, a limb, the tail, it is
designated by the term local paralysis. When the irritation extends from
the periphery of the center it is termed reflex paralysis.
Causes are much varied. Most of the acute affections of the brain and
spinal cord may lead to paralysis. Injuries, tumors, disease of the
blood vessels of the brain, etc., all have a tendency to produce
suspension of the conducting motive power to the muscular structures.
Pressure upon, or the severing of, a nerve causes a paralysis of the
parts to which such a nerve is distributed. Apoplexy may be termed a
general paralysis, and in nonfatal attacks is a frequent cause of the
various forms of palsy.
GENERAL PARALYSIS.--This can not take place without producing immediate
death. The term is, however, usually applied to paralysis of the four
extremities, whether any other portions of the body are involved or not.
This form of palsy is due to compression of the brain by congestion of
its vessels, large clot formation in apoplexy, concussion, or shock, or
any disease in which the whole brain structure is involved in functional
disturbance.
HEMIPLEGIA (PARALYSIS OF ONE SIDE OR HALF OF THE BODY).--Hemiplegia is
frequently the result of a tumor in the lateral ventricles of the brain,
softening of one hemisphere of the cerebrum, pressure from extravasated
blood, fracture of the cranium, or it may be due to poisons in the blood
or to reflex origin. When hemiplegia is due to or the result of a prior
disease of the brain, especially of an inflammatory character, it is
seldom complete; it may affect only one limb and one side of the head,
neck, or muscles along the back, and may pass off in a few days after
the disappearance of all the other evidences of the primary affection.
In most cases, however, hemiplegia arises from emboli obstructing one or
more blood vessels of the brain, or the rupture of some vessel the wall
of which had become weakened by degeneration and the extravasation of
blood. Sensibility in most cases is not impaired, but in some there is a
loss of sensibility as well as of motion. In some cases the bladder and
rectum are involved in the paralysis.
_Symptoms._--In hemiplegia the attack may be very sudden, and the animal
fall, powerless to move one side of the body; one side of the lips will
be relaxed; the tongue may hang out on one side of the mouth; the tail
curved around sideways; an inability to swallow feed or water may be
present, and often the urine dribbles away as fast as it collects in the
bladder. Sensibility of the affected side may be entirely lost or only
partial; the limbs may be cold and sometimes unnaturally warm. In cases
wherein the attack is not so severe the animal may be able to maintain
the standing position, but will have great difficulty in moving the
affected side. In such cases the animal may recover from the disability.
In the more severe, in which there is complete loss of power of
movement, recoveries are rare.
PARAPLEGIA (TRANSVERSE PARALYSIS OF THE HIND EXTREMITIES).--Paralysis of
the hind extremities is usually due to some injury or inflammation
affecting the spinal cord. (See "Spinal meningitis," p. 232, and
"Myelitis," p. 233.) It may also be due to a reflex irritation from
disease of peripheral nerves, to spinal irritation or congestion caused
by blood poisons, etc.
_Symptoms._--When due to mechanical injury of the spinal cord, from a
broken back or spinal hemorrhage, it is generally progressive in its
character, although it may be sudden. When it is caused by agents in the
blood, it may be intermittent or recurrent.
Paraplegia is not difficult to recognize, for it is characterized by a
weakness and imperfect control of the hind legs and powerless tail. The
urine usually dribbles away as it is formed and the manure is pushed
out, ball by ball, without any voluntary effort, or the passages may
cease entirety. When paraplegia is complete, large and ill-conditioned
sores soon form on the hips and thighs from chafing and bruising, which
have a tendency quickly to weaken the animal and necessitate his
destruction.
LOCOMOTOR ATAXIA, OR INCOORDINATION OF MOVEMENT.--This is characterized
by an inability to control properly the movement of the limbs. The
animal appears usually perfectly healthy, but when he is led out of his
stall his legs have a wobbly movement and he will stumble or stagger,
especially in turning. When this is confined to the hind parts it may be
termed a modified form of paraplegia, but often it may be seen to affect
nearly all the voluntary muscles when they are called into play, and
must be attributed to some pressure exerted on the base of the brain.
LOCAL PARALYSIS.--This is frequently met with in horses. It may affect
many parts of the body, even vital organs, and it is very frequently
overlooked in diagnosis.
FACIAL PARALYSIS.--This is a frequent type of local paralysis, and is
due to impairment of function of the motor nerve of the facial muscles,
the portio dura. The cause may exist at the base of the brain,
compression along its course after it leaves the medulla oblongata, or
to a bruise after it spreads out on the great masseter muscle.
_Symptoms._--A flaccid condition of the cheek muscles, pendulous lips,
inability to grasp the feed, often a slow and weak movement in chewing,
and difficulty and slowness in drinking.
LARYNGISMUS PARALYTICUS, OR ROARING.--This condition is characterized by
roaring, and is usually caused by an inflamed or hypertrophied bronchial
gland pressing against the left recurrent laryngeal nerve, which
interferes with its conducting power. A similar condition is
occasionally induced in acute pleurisy, when the recurrent nerve becomes
involved in the diseased process or compressed by plastic exudation.
PARALYSIS OF THE RECTUM AND TAIL.--This is generally the result of a
blow or fall on the rump, which causes a fracture of the sacrum bone and
injury to the nerves supplying the tail and part of the rectum and
muscles belonging thereto. This fracture would not be suspected were it
not for the loss of motion of the tail.
INTESTINAL PARALYSIS.--Characterized by persistent constipation;
frequently the strongest purgatives have no effect whatever on the
movement of the bowels. In the absence of symptoms of indigestion, or
special diseases implicating the intestinal canal, torpor of the bowels
must be attributed to deficient innervation. This condition may depend
upon brain affections or be due to reflex paralysis. Sudden checks of
perspiration may induce excessive action of the bowels or paralysis.
PARALYSIS OF THE BLADDER.--This usually affects the neck of the bladder,
and is characterized by incontinence of urine; the urine dribbles away
as fast as it is secreted. The cause may be of reflex origin, disease
of the rectum, tumors growing within the pelvic cavity, injury to the
spinal cord, etc.
PARALYSIS OF THE OPTIC NERVE (AMAUROSIS).--A paralysis of eyesight may
occur very suddenly from rupture of a blood vessel in the brain, acute
local congestion of the brain, the administration of excessive doses of
belladonna or its alkaloid atropia, etc. In amaurosis the pupil is
dilated to its full extent; the eye looks clear, but does not respond to
light.
Paralysis of hearing, of the external ear, of the eyelid, partial
paralysis of the heart and organs of respiration, of the blood vessels
from injury to the vasomotor nerves of the esophagus, or loss of
deglutition, palsy of the stomach, all may be manifested when the supply
of nervous influence is impaired or suspended.
TREATMENT FOR PARALYSIS.--In all paralytic affections there may be
anesthesia, or impairment of sensibility, in addition to the loss of
motion, or there may be hyperesthesia, or increased sensibility, in
connection with the loss of motion. These conditions may call for
special treatment in addition to that for loss of motion. If
hyperesthesia is well marked local anodynes may be needed to relieve
suffering. Chloroform liniment or hypodermic injections of from 3 to 5
grains of sulphate of morphia will allay local pain. If there is marked
anesthesia, or loss of sensibility, it may become necessary to secure
the animal in such way that he can not suffer serious injury from
accidents which he can not avoid or feel. In the treatment of any form
of paralysis we must always refer to the cause, and attempt its removal
if it can be discovered. In cases in which the cause can not be
determined we have to rely solely upon a general external and internal
treatment. Externally, fly blisters or strong, irritant liniments may be
applied to the paralyzed parts. In hemiplegia they should be applied
along the bony part of the side of the neck; in paraplegia, across the
loins. In, some cases hot-water cloths will be beneficial. Internally,
it is well to administer 1 dram of powdered nux vomica or 2 grains of
sulphate of strychnia twice a day until twitching of some of the
voluntary muscles occurs; then discontinue it for several days, and then
commence again with a smaller dose, gradually increasing it until
twitching recurs. Iodid of potassium in 1 to 2 dram doses two or three
times daily may be used with the hope that it will favor the absorption
of the clot or obstruction to the nervous current. In some cases
Fowler's solution of arsenic in teaspoonful doses twice a day in the
drinking water proves beneficial. Occasionally benefit may be derived
from the application of the electric current, especially in cases of
roaring, facial paralysis, paralysis of the eyelid, etc. Nutritious but
not too bulky feed, good ventilation, clean stabling, moderate exercise
if the animal is capable of taking it, good grooming, etc., should be
observed in all cases.
SPINAL MENINGITIS, OR INFLAMMATION OF THE MEMBRANES ENVELOPING THE
SPINAL CORD.
This may be induced by the irritant properties of blood poisons,
exhaustion and exposure, spinal concussion, all forms of injury to the
spine, tumors, caries of the vertebrae, rheumatism, etc.
_Symptoms._--A chill may be the precursor, a rise in temperature, or a
general weakness and shifting of the legs. Soon a painful, convulsive
twitching of the muscles sets in, followed by muscular rigidity along
the spine, in which condition the animal will move very stiffly and
evince great pain in turning. Evidences of paralysis or paraplegia
develop, retention or incontinence of urine, and oftentimes sexual
excitement is present. The presence of marked fever at the beginning of
the attack, associated with spinal symptoms, should lead us to suspect
spinal meningitis or myelitis. These two conditions usually appear
together, or myelitis follows inflammation of the meninges so closely
that it is almost impossible to separate the two; practically it does
not matter much, for the treatment will be about the same in both cases.
Spinal meningitis generally becomes chronic, and is then marked
principally by paralysis of that portion, or parts of it, posterior to
the seat of the disease.
_Pathology._--In spinal meningitis we find essentially the same
condition as in cerebral meningitis; there is an effusion of serum
between the membranes, and often a plastic exudation firmly adherent to
the pia mater serves to maintain a state of paralysis for a long time
after the acute symptoms have disappeared by compressing the cord.
Finally, atrophy, softening, and even abscess may develop within the
cord. Unlike in man, it is usually found localized in horses.
_Treatment._--Bags filled with ice should be applied along the spine, to
be followed later by strong blisters. The fever should be controlled as
early as possible by giving 20 drops of Norwood's tincture of veratrum
viride every hour until the desired result is obtained. One dram of the
fluid extract of belladonna, to control pain and vascular excitement of
the spinal cord, may be given every five or six hours until the pupils
of the eyes become pretty well dilated. If the pain is very intense 5
grains of sulphate of morphia should be injected hypodermically. The
animal must be kept as free from excitement as possible. If the urine is
retained in the bladder it must be drawn off every four or six hours. In
very acute attacks the disease generally proves fatal in a few days. If,
however, the animal grows better, some form of paralysis is liable to
remain for a long time, and the treatment will have to be directed then
toward a removal of the exudative products and a strengthening of the
system and stimulation of the nervous functions. To induce absorption,
iodid of potassium in 2-dram doses, dissolved in the drinking water, may
be given twice a day. To strengthen the system, iodid of iron 1 dram
twice a day and 1 dram of nux vomica once a day may be given in the
feed. Electricity to the paralyzed and weakened muscles is advisable;
the current should be weak, but be continued for half an hour two or
three times daily. If the disease is due to a broken back, caries of the
vertebrae, or some other irremediable cause, the animal should be
destroyed at once.
MYELITIS, OR INFLAMMATION OF THE SUBSTANCE OF THE SPINAL CORD.
This is a rare disease, except as a secondary result of spinal
meningitis or injuries to the spine. Poisoning by lead, arsenic,
mercury, phosphorus, carbonic-acid gas, etc., has been known to produce
it. Myelitis may be confined to a small spot in the cord or may involve
the whole for a variable distance. It may lead to softening abscess or
degeneration.
_Symptoms._--The attack may begin with a chill or convulsion; the
muscles twitch or become cramped very early in the disease, and the
bladder usually is affected at the outset, in which there may be either
retention or incontinence of urine. These conditions are followed by
complete or partial paralysis of the muscles posterior to the locality
of the inflamed cord, and the muscles begin to waste away rapidly. The
paralyzed limb becomes cold and dry, due to the suspension of proper
circulation; the joints may swell and become edematous; vesicular
eruptions appear on the skin; and frequently gangrenous sloughs form on
the paralyzed parts. It is exceedingly seldom that recovery takes place.
In a few instances it may assume a chronic type, when all the symptoms
become mitigated, and thus continue for some time, until septicemia,
pyemia, or exhaustion causes death.