Special Report on Diseases of Cattle - Part 16
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Part 16

[See discussion of this disease in chapter on "Infectious diseases," p.

358.]

LIGHTNING STROKE (ASPHYXIA ELECTRICA).

When an animal is struck by lightning the shock is instantaneously expended on the nervous system, and as a rule death occurs immediately; but when the shock is not fatal animation is suspended to a greater or less extent, as evidenced by prostration, unconsciousness, and paralysis.

_Symptoms._--When not fatal, the symptoms vary much, according to the severity of the shock. The animal usually falls, as from an apoplectic attack, and, as a matter of course, the symptoms are such as are generally manifested in connection with concussion of the brain. The muscular system may be completely relaxed; the legs limber; the muscles flabby and soft to the touch; or there may be convulsions, spasms, and twitching of the muscles. The breathing is generally labored, irregular, or interrupted, and slower than normal. In most instances the electrical fluid leaves its mark by singeing the hair, or by inflicting wounds, burns, or blisters.

_Treatment._--So long as the beating of the heart is perceptible the endeavor to resuscitate the animal should be continued. Dash cold water over the head and body; rub the body and legs; smartly whip the body with wet towels or switches. Mustard, mixed with water, should be well rubbed over the legs and back of the head on each side of the neck. Inject into the r.e.c.t.u.m 4 drams of stronger liquor ammonia, or 1-1/2 ounces of hartshorn diluted with a quart of warm water. Cautiously hold an uncorked bottle of hartshorn to the nostrils, so that some of it is inhaled, but care should be taken that too much is not suddenly inhaled. If the animal is unconscious, hypodermic injections of stimulants are indicated, such as 6 drams of camphorated oil in one dose, subcutaneously, or 20 grains of caffein or 1/2 grain of strychnin, also subcutaneously.

When the animal revives sufficiently to be able to swallow, 4 drams of the stronger liquor ammonia, diluted with a quart of cold water, should be given as a drench, and the dose should be repeated in an hour. One and one-half ounces of ordinary hartshorn may be used instead of the stronger liquor ammonia, but, like the latter, it should be diluted with a quart or more of water, and even then care should be exercised in drenching.

In cases where the shock has not caused complete insensibility recovery may be hastened by the ammonia and water drench, or 4 ounces of brandy diluted with a quart of water, or 8 ounces of whisky diluted with a quart of water.

These doses may be given every three or four hours if necessary. After recovery from the more serious symptoms 2 drams of sulphate of quinin should be given twice a day until health is restored. If any paralysis remains 1-1/2 drams of pulverized nux vomica should be given twice a day with the quinin.

The foregoing treatment is also applicable when the electrical shock is given by telephone, electric car, or electric-light wires, etc. The wounds, burns, or blisters should be treated according to the antiseptic method of treating wounds.

TUMORS IN THE BRAIN, ETC.

Tumors of different kinds have been found within the cranial cavity, and in many cases there have been no well-marked symptoms exhibited during the life of the animal to lead one to suspect their existence. Cases are recorded where bony tumors have been found in the brain of cattle that died suddenly, but during life no signs of disease were manifested. Post-mortem examinations have disclosed tubercles in the membranes of the brain. (See "Tuberculosis," p. 407.) Abscesses, usually the result of inflammation of the brain, have been found post-mortem. For the description of hydrocephalus, or dropsy of the brain, of calves the reader is referred to the section on parturition. (See "Water in the head," p. 179.)

Ch.o.r.ea, constant twitching and irregular spasmodic movements of the muscles, has been noticed in connection with or as a sequel to other affections, as, for example, parturient apoplexy.

Various diseases, the description of which will be found in other sections of this work, affect the nervous system to a greater or less extent--for example, ergotism, lead poisoning, uremia, parturient apoplexy, colic, and other affections a.s.sociated with cramps, or spasms, etc. Disease of the ovaries or of the spinal cord, by reflex irritation, may cause estromania (see "Excess of venereal desire," p. 148, constant desire for the bull).

DISEASES OF THE URINARY ORGANS.

By JAMES LAW, F. R. C. V. S.,

_Formerly Professor of Veterinary Science, etc., in Cornell University._

Of the materials that have served their purpose in building up the animal body or in sustaining the body temperature, and that are now to be thrown out as waste, the greater part is expelled from the system through the lungs and the kidneys, but the agents that pa.s.s out by either of these two channels differ in the main from those pa.s.sing by the other. Thus from the lungs in the form of dioxid of carbon--the same gas that comes from burning of coal or oil--there escapes most of the waste material resulting from the destruction in the system of fats, sugars, starch, and such other foods as are wanting in the element nitrogen, and do not form fibrous tissues, but go mainly to support animal heat or maintain functional activity. From the kidneys, on the other hand, are thrown out the waste products resulting from the destruction of the foods and tissues containing nitrogen--of, for instance, alb.u.min, fibrin, gluten, casein, gelatin, woody tissue, etc.

While much of the waste material containing nitrogen leaves the body by the bowels, this is virtually only such of the alb.u.minoid food as has failed to be fully digested and absorbed; this has never formed a true const.i.tuent part of the body itself or of the blood, but is so much waste food, like that which has come to the table and again carried away unused. If the alb.u.minoid food element has entered the blood, whether or not it has been built up into a const.i.tuent part of the structure of the body, its waste products, which contain nitrogen, are in the main expelled through the kidneys, so that the latter become the princ.i.p.al channels for the expulsion of all nitrogen-containing waste.

It would be an error, however, to infer that all nitrogenous food, when once digested and absorbed into the blood, must necessarily leave the system in the urine. On the contrary, in the young and growing animal, all increase of the fibrous structures of the body is gained through the building up of those flesh-forming const.i.tuents into their substance; in the pregnant animal the growth of the offspring and its envelopes has a similar origin, and in the dairy cow the casein or curd of the milk is a means of constant elimination of these nitrogen-containing agents. Thus, in the breeding cow and, above all, in the milking cow, the womb or udder carries on a work in one sense equivalent to that otherwise performed by the kidneys. Not only are these organs alike channels for the excretion of alb.u.minous products, but they are also related to each other structurally and by nervous sympathy, so that suffering in the one is liable to induce some measure of disorder in the other.

As in the case of other mammals, this nitrogenous waste matter is mainly present in the urine of cattle in the form of urea, but also, to some extent, as hippuric acid, a derivative of vegetable food which, in the herbivora, replaces the uric acid found in the urine of man and carnivora.

Uric acid is, however, found in the urine of sucking calves which have practically an animal diet, and it may also appear in the adult in case of absolute, prolonged starvation, and in diseases attended with complete loss of appet.i.te and rapid wasting of the body. In such cases the animal lives on its own substance, and the product is that of the wasting flesh.

The other products containing nitrogen are present in only small quant.i.ties and need not be specially referred to. The urine of cattle contains much less of carbonates than that of the horse, and effervesces less on the addition of an acid. As the carbonates form a large proportion of the solid deposits (gravel, stone) from the horse's urine, the ox may thus be held less liable, yet even in the ox the carbonates become abundant or scanty, according to the nature of the feed, and therefore gravel, formed by carbonate of lime, is not infrequent in cattle. When fed on beets, clover hay, or bean straw carbonates are present in large quant.i.ties, these aliments being rich in organic acids and alkaline carbonates; whereas upon oat straw, barley straw, and, above all, wheat straw, they are in small amount. In calves fed on milk alone no carbonates are found in the urine.

Phosphates, usually in combination with lime, are, as a rule, present only in traces in the urine of cattle; however, on a dietary of wheat, bran, or other aliment rich in phosphates, these may be present in large amount, so that they render the liquid cloudy or are deposited in solid crystals. The liquid is rendered transparent by nitric acid.

The cow's urine, on a diet of hay and potatoes, contained:

Parts.

Urea 18.5 Pota.s.sic hippurate 16.5 Alkaline lactates 17.2 Pota.s.sium bicarbonate 16.1 Magnesium carbonate 4.7 Lime carbonate 0.6 Pota.s.sium sulphate 3.6 Common salt 1.5 Silica Trace Phosphates 0.0 Water and undetermined substances 921.3 _______ Total 1,000.0

The following table after Tereg[1] gives the different conditions of the urine, and especially the amount of urea and hippuric acid under different rations. The subjects were two oxen, weighing, respectively, 1,260 pounds and 1,060 pounds:

--------------+------+-----+-----+-----+-----+-----+------+-----+-----+---- Food per day.|Water.

(pounds) | |Urine | |Pa.s.sed.

| | |Density.

| | | |Solids | | | |in urine.

| | | | |Hippuric | | | | |acid.

| | | | | |Urea.

| | | | | | |Nitrogen | | | | | | |in hippuric | | | | | | |acid and | | | | | | |urea.

| | | | | | | |Total | | | | | | | |nitrogen.

| | | | | | | | |Urea | | | | | | | | |per day.

| | | | | | | | | |Hip- | | | | | | | | | |puric | | | | | | | | | |acid | | | | | | | | | |per | | | | | | | | | |week --------------+------+-----+-----+-----+-----+-----+-----+-----+-----+----- |_Lbs._|_Lbs_| |_Pct_|_Pct_|_Pct_|_Pct_|_Pct_|_Ozs_|_Ozs_ 16.90 wheat | | | | | | | | | | straw, and | 46.46| 7.40|1,036| 8.41| 2.66| 1.33| 0.83| 0.94| 1.63|3.23 1.30 bean | | | | | | | | | | meal | | | | | | | | | | | | | | | | | | | | 14.70 oat | | | | | | | | | | straw, and | 61.10|15.26|1,039| 6.93| 2.09| 0.84| 0.55| 0.49| 2.2 |5.3 2.30 bean | | | | | | | | | | meal | | | | | | | | | | | | | | | | | | | | 10.4 wheat | | | | | | | | | | straw, 10.4 | 71.76|12.36|1,043| 8.05| 0.95| 1.85| 0.93| 0.94| 3.83|1.96 clover hay, | | | | | | | | | | 0.6 bean | | | | | | | | | | meal, and | | | | | | | | | | 2.6 starch | | | | | | | | | | | | | | | | | | | | 10.4 wheat | | | | | | | | | | straw, 10.4 | 80.54|12.46|1,044| 8.29| 8.07| 2.41| 1.19| 1.11| 5.8 |2.1 clover hay, | | | | | | | | | | 2.7 bean | | | | | | | | | | meal, 1.4 | | | | | | | | | | starch, and | | | | | | | | | | 0.8 sugar | | | | | | | | | | | | | | | | | | | | 10.4 wheat | | | | | | | | | | straw, 10.4 | 78.96|17.62|1,043| 8.41| 0.74| 3.12| 1.45| 1.24| 9.17|2.17 clover hay, | | | | | | | | | | 5 bean meal, | | | | | | | | | | and 0.8 sugar | | | | | | | | | | | | | | | | | | | | 10 wheat | | | | | | | | | | straw, 10 |110.12|25.86|1,038| 7.00| 0.31| 2.49| 1.19| 1.25|10.9 |1.33 clover hay, | | | | | | | | | | 6.4 bean | | | | | | | | | | meal, 1.7 | | | | | | | | | | starch, 4 | | | | | | | | | | sugar, and | | | | | | | | | | 0.4 rape oil | | | | | | | | | | | | | | | | | | | | 10 wheat | | | | | | | | | | straw, 10 |101.80|27.04|1,037| 7.14| 0.20| 2.95| 1.39| 1.58|13.3 |0.9 clover hay, | | | | | | | | | | 9.4 bean | | | | | | | | | | meal, 3.1 | | | | | | | | | | sugar, and | | | | | | | | | | 0.4 rape oil | | | | | | | | | | | | | | | | | | | | 10 wheat | | | | | | | | | | straw, 10 |119.00|23.20|1,038| 7.74| 0.21| 4.06| 1.91| 1.69|15.4 |0.8 clover hay, | | | | | | | | | | 11.7 bean | | | | | | | | | | meal, 2.8 | | | | | | | | | | starch, and | | | | | | | | | | 0.5 rape oil | | | | | | | | | | | | | | | | | | | | 17.86 bean | | | | | | | | | | straw, and | 54.84|12.60|1,043| 7.06| 0.40| 2.53| 1.21| 1.15| 5.3 |0.83 1.6 bean meal | | | | | | | | | | | | | | | | | | | | 14.88 bean | | | | | | | | | | straw | 55.76|16.34|1,036| 5.45| 0.11| 1.41| 0.67| 0.64| 3.83|0.3 | | | | | | | | | | 16.90 meadow | | | | | | | | | | hay | 36.26|15.14|1,042| 7.91| 1.30| 1.73| 0.91| 0.92| 4.37|3.3 --------------+------+-----+-----+-----+-----+-----+-----+-----+-----+-----

The varying quant.i.ty of urea (from 1.6 to 15.4 ounces) is most suggestive as to the action of the more or less nitrogenous feed and the resulting concentration of the urine and blood. Hippuric acid, on the other hand, is most abundant when the animal is fed on hay and straw.

The specific gravity of the urine of cattle varies from 1,030 to 1,060 in health, water being 1,000. It is transparent, with a yellowish tinge, and has a characteristic, musky smell. The chemical reaction is alkaline, turning red litmus paper blue. The quant.i.ty pa.s.sed in twenty-four hours varies greatly, increasing not only with the water drunk, but with the alb.u.minoids taken in with the feed and the urea produced. If a solution of urea is injected into the veins the secretion of urine is greatly augmented. Similarly the excess of salts like carbonate of potash in the feed, or of sugar, increases the action of the kidneys. Only about 20 per cent of the water swallowed escapes in the urine, the remaining 80 per cent pa.s.sing mostly from the lungs, and to a slight extent by the bowels. The skin of the ox does not perspire so readily nor so freely as that of the horse; hence the kidneys and lungs are called upon for extra work. The influence of an excess of water in the feed is most remarkable in swill-fed distillery cattle, which urinate profusely and frequently, yet thrive and fatten rapidly.

Among the other conditions that increase the flow of urine is overfilling of (internal pressure in) the blood vessels of the kidneys; hence the contraction of the blood vessels of the skin by cold drives the blood inward, tends to dilate the blood vessels of the kidneys, and to increase the secretion of urine. Nervous disorders, such as excitement, fear, congestions, or structural injuries to the back part of the base of the brain, have a similar result, hence, doubtless, the action of certain fungi growing in musty hay or oats in producing profuse flow of urine, whereas other forms of musty fodder cause stupor, delirium, or paralysis. Bacteria and their products are mainly expelled by the kidneys, and become sources of local infection, irritation, and disease.

The quant.i.ty of urine pa.s.sed daily by an ox on dry feeding averages 7 to 12 pints, but this may be increased enormously on a watery diet.

The mutual influence of the kidneys and other important organs tends to explain the way in which disease in one part supervenes on preexisting disorder in another. The introduction of alb.u.minoids in excess into the blood means the formation of an excess of urea, and a more profuse secretion of urine, of a higher specific gravity, and with a greater tendency to deposit its solid const.i.tuents, as gravel, in the kidneys or bladder. A torpid action of the liver, leaving the alb.u.minoids in transition forms, less soluble than the urea into which they should have been changed, favors the onset of rheumatism or of nervous disorder, the deposit of such alb.u.minoid products in the kidneys, the formation of a deep-brown or reddish urine, and congestion of the kidneys. Any abnormal activity of the liver in the production of sugar--more than can be burned up in the circulation--overstimulates the kidneys and produces increased flow of a heavy urine with a sweetish taste. This increased production of sugar may be primarily due to disease of the brain, which, in its turn, determines the disorder of the liver. Disease of the right side of the heart or of the lungs, by obstructing the onward flow of blood from the veins, increases the blood pressure in the kidneys and produces disorder and excessive secretion. Inactivity of the kidneys determines an increase in the blood of waste products, which become irritating to different parts, producing skin eruptions, itching, dropsies, and nervous disorders. Sprains of the loins produce bleeding from the kidneys and disease of the spinal cord, and sometimes determine alb.u.minous or milky looking urine.

The kidney of the ox (Pl. IX, fig. 1) is a compound organ made up of 15 to 25 separate lobules like so many separate kidneys, but all pouring their secretion into one common pouch (pelvis) situated in an excavation in the center of the lower surface. While the ox is the only domesticated quadruped which maintains this divided condition of the kidney after birth, this condition is common to all while at an early stage of development in the womb. The cl.u.s.ter of lobules making up a single kidney forms an ovoid ma.s.s flattened from above downward, and extending from the last rib backward beneath the loins and to one side of the solid chain of the backbone. The right is more firmly attached to the loins and extends farther backward than the left. Deeply covered in a ma.s.s of suet, each kidney has a strong outer, white, fibrous covering, and inside this two successive layers of kidney substance, of which the outer is that in which the urine is mainly separated from the blood and poured into the fine, microscopic urinary ducts. (Pl. X, fig. 1) These latter, together with blood vessels, lymph vessels, and nerves, make up the second, or internal, layer. The outer layer is mainly composed of minute globular cl.u.s.ters of microscopic, intercommunicating blood vessels (Malpighian bodies), each of which is furnished with a fibrous capsule that is nothing else than the dilated commencement of a urine tube. These practically microscopic tubes follow at first a winding course through the outer layer (Ferrein's tubes), then form a long loop (doubling on itself) in the inner layer (Henle's loop), and finally pa.s.s back through the inner layer (Bellini's tubes) to open through a conical process into the common pouch (pelvis) on the lower surface of the organ. (Pl. X, figs. 1, 2, 3.)

The tube that conveys the urine from the kidney to the bladder is like a white, round cord, about the size of a goose quill, prolonged from the pouch on the lower surface of the kidney backward beneath the loins, then inward, supported by a fold of thin membrane, to open into the bladder just in front of its neck. The ca.n.a.l pa.s.ses first through the middle (muscular) coat of the bladder, and then advances perceptibly between that and the internal (mucous) coat, through which it finally opens. By this arrangement in overfilling the bladder this opening is closed like a valve by the pressure of the urine, and the return of liquid to the kidney is prevented.

The bladder (Pl. IX, fig. 2) is a dilatable, egg-shaped pouch, closed behind by a strong ring of muscular fibers encircling its neck, and enveloped by looped, muscular fibers extending on all sides around its body and closed anterior end. Stimulated by the presence of urine, these last contract and expel contents through the neck into the urethra. This last is the tube leading backward along the floor of the pelvic bones and downward through the p.e.n.i.s. In the bull this ca.n.a.l of the urethra is remarkable for its small caliber and for the S-shaped bend which it describes in the s.p.a.ce between the thighs and just above the s.c.r.o.t.u.m. This bend is attributable to the fact that the retractor muscles are attached to the p.e.n.i.s at this point, and in withdrawing that organ within its sheath they double it upon itself. The small size of the ca.n.a.l and this S-shaped bend are serious obstacles to the pa.s.sing of a catheter to draw the urine, yet by extending the p.e.n.i.s out of its sheath the bend is effaced, and a small, gum-elastic catheter, not more than one-fourth of an inch in diameter, may with care be pa.s.sed into the bladder. In the cow the urethra is very short, opening in the median line on the floor of the v.u.l.v.a about 4 inches in front of its external orifice. Even in her, however, the pa.s.sing of a catheter is a matter of no little difficulty, the opening of the urethra being very narrow and encircled by the projecting membranous and rigid margins, and on each side of the opening is a blind pouch (ca.n.a.l of Gartner) into which the catheter will almost invariably find its way. In both male and female, therefore, the pa.s.sing of a catheter is an operation which demands special skill.

_General symptoms of urinary disorders._--These are not so prominent in cattle as in horses, yet they are of a similar kind. There is a stiff or straddling gait with the hind legs and some difficulty in turning or in lying down and rising, the act causing a groan. The frequent pa.s.sage of urine in driblets, its continuous escape in drops, the sudden arrest of the flow when in full stream, the rhythmic contraction of the muscles under the a.n.u.s without any flow resulting, the swelling of the sheath, the collection of hard, gritty ma.s.ses on the hair surrounding the orifice of the sheath, the occurrence of dropsies in the limbs under the chest or belly, or in either of these cavities, and finally the appearance of nervous stupor, may indicate serious disorder of the urinary organs. The condition of the urine pa.s.sed may likewise lead to suspicion. It may be white, from crystallized carbonate of lime; brown, red, or even black, from the presence of blood or blood-coloring matter; yellow, from biliary coloring matter; frothy, from contained alb.u.min; cloudy, from phosphates; glairy, from pus; it may also show gritty ma.s.ses from gravel. In many cases of urinary disorder in the ox, however, the symptoms are by no means prominent, and unless special examination is made of the loins, the bladder, and the urine the true nature of the malady may be overlooked.

DIURESIS (POLYURIA, DIABETES INSIPIDUS, EXCESSIVE SECRETION OF URINE).

A secretion of urine in excess of the normal amount may be looked on as disease, even if the result does not lead to immediate loss of condition.

Cattle fed on distillery swill are striking examples of such excess caused by the enormous consumption of a liquid feed, which nourishes and fattens in spite of the diuresis; the condition is unwholesome, and cattle that have pa.s.sed four or five months in a swill stable have fatty livers and kidneys, and never again do well on ordinary feed. Diuresis may further occur from increase of blood pressure in the kidneys (diseases of the heart or lungs which hinder the onward pa.s.sage of the blood, the eating of digitalis, English broom, the contraction of the blood vessels on the surface of the body in cold weather, etc.); also from acrid or diuretic plants taken with the feed (dandelion, burdock, colchic.u.m, digitalis, savin, resinous shoots, etc.); from excess of sugar in the feed (beets, turnips, ripe sorghum); also from the use of frozen feed (frosted turnip tops and other vegetables), and from the growths of certain molds in fodder (musty hay, mow-burnt hay, moldy oats, moldy bread, etc.). Finally, alkaline waters and alkaline incrustations on the soil may be active causes. In some of these cases the result is beneficial rather than injurious, as when cattle affected with gravel in the kidneys are entirely freed from this condition by a run at gra.s.s, or by an exclusive diet of roots or swill. In other cases, however, the health and condition suffer, and even inflammation of the kidneys may occur.

_Treatment._--The treatment is mainly in the change of diet to a more solid aliment dest.i.tute of the special, offensive ingredient. Boiled flaxseed is often the best diet or addition to the wholesome dry food, and, by way of medicine, doses of 2 drams each of sulphate of iron and iodid of pota.s.sium may be given twice daily. In obstinate cases 2 drams ergot of rye or of catechu may be added.

b.l.o.o.d.y URINE (RED WATER, MOOR ILL, WOOD ILL, HEMATURIA, HEMAGLOBINURIA).

This is a common affection among cattle in certain localities, above all on damp, undrained lands and under a backward agriculture. It is simply b.l.o.o.d.y urine or hematuria when the blood is found in clots, or when under the microscope the blood globules can be detected as distinctly rounded, flattened disks. It is smoky urine--hemaglobinuria--when neither such distinct clots nor blood disks can be found, but merely a general browning, reddening, or blackening of the urine by the presence of dissolved, blood-coloring matter. The b.l.o.o.d.y urine is the more direct result of structural disease of the kidneys or urinary pa.s.sages (inflammation, stone, gravel, tumors, hydatids, kidney worms, sprains of the loins), while the stained urine (hemaglobinuria) is usually the result of some general or more distinct disorder in which the globules are destroyed in the circulating blood and the coloring matter dissolved in and diffused through the whole ma.s.s of the blood and of the urine secreted from it. As in the two forms, blood and the elements of blood escape into the urine, alb.u.min is always present, so that there is alb.u.minuria with blood-coloring matter superadded. If from stone or gravel, gritty particles are usually pa.s.sed, and may be detected in the bottom of a dish in which the liquid is caught.

If from fracture or severe sprain of the loins, it is liable to be a.s.sociated not only with some loss of control of the hind limbs and with staggering behind but also with a more or less perfect paralysis of the tail. The bloodstained urine without red globules results from specific diseases--Texas fever (Pl. XLVII, fig. 3), anthrax, spirillosis, and from eating irritant plants (broom, savin, mercury, h.e.l.lebore, ranunculus, convolvulus, colchic.u.m, oak shoots, ash privet, hazel, hornbeam, and other astringent, acrid, or resinous plants, etc.). The Maybug or Spanish fly taken with the feed or spread over a great extent of skin as a blister has a similar action. Frosted turnips or other roots will bring on the affection in some subjects. Among conditions which act by the direct destruction of the globules in the circulating blood may be named an excess of water in that fluid; the use of water from soils rich in decomposing vegetable matter and containing alkaline salts, particularly nitrites; and the presence in the water and feed of the ptomaines of bacteria growth; hence the prevalence of "red water" in marshy districts and on clayey and other impervious soils, and the occurrence of b.l.o.o.d.y urine in the advanced stages of several contagious diseases. Some mineral poisons--such as iodin, a.r.s.enic, and phosphorus taken to excess--may cause hematuria, and finally the symptoms may be merely the result of a const.i.tutional predisposition of the individual or family to bleeding. In some predisposed subjects, exposure of the body to cold or wet will cause the affection.