This disease is not only peculiar to the cow, but it may be said to be virtually confined to the improved and plethoric cow. It further occurs only at or near the time of calving. Indeed, these two factors, calving and plethora, may be set apart as preeminently the causes of this disease. It is the disease of cows that have been improved in the direction of early maturity, power of rapid fattening, or a heavy yield of milk, and hence it is characteristic of those having great appet.i.tes and extraordinary power of digestion. The heavy milking breeds are especially its victims, as in them the demand for the daily yield of 50 to 100 pounds of milk means even more than a daily increase of 2 to 3 pounds of body weight, mainly fat. The victims are not always fat when attacked, but they are cows having enormous powers of digestion, and which have been fed heavily at the time. Hence the stall-fed, city-dairy cow, and the farm cow on a rich clover pasture in June or July are especially subject. The condition of the blood globules in the suffering cow attests the extreme richness and density of the blood, yet this peculiarity appears to have entirely escaped the notice of veterinary writers. I have never examined the blood of a victim of this disease without finding the red-blood globules reduced to little more than one-half their usual size. Now, these globules expand or contract according to the density of the liquid in which they float. If we dilute the blood with water they will expand until they burst, whereas if solids, such as salt or alb.u.min, are added they shrink to a large extent. Their small size, therefore, in parturition fever indicates the extreme richness of the blood, or, in other words, plethora.

Confinement in the stall is an accessory cause, partly because stabled cattle are highly fed, partly because the air is hotter and fouler, and partly because there is no expenditure by exercise of the rich products of digestion.

High temperature is conducive to the malady, though the extreme colds of winter are no protection against it. Heat, however, conduces to fever, and fever means lessened secretion, which means a plethoric state of the circulation. The heats of summer are, however, often only a coincidence of the real cause, the mature rich pastures, and especially the clover ones, being the greater.

Electrical disturbances have an influence of a similar kind, disturbing the functions of the body and favoring sudden variations in the circulation. A succession of cases of the malady often accompany or precede a change of weather from dry to wet, from a low to a high barometric pressure.

Costiveness, which is the usual concomitant of fever, may in a case of this kind become an accessory cause, the retention in the blood of what should have pa.s.sed off by the bowels tending to increase the fullness of the blood vessels and the density of the blood.

Mature age is a very strong accessory cause. The disease never occurs with the first parturition, and rarely with the second. It appears with the third, fourth, fifth, or sixth--after the growth of the cow has ceased and when all her powers are devoted to the production of milk.

Calving is an essential condition, as the disturbance of the circulation consequent on the contraction of the womb and the expulsion into the general circulation of the enormous ma.s.s of blood hitherto circulating in the walls of the womb fills to repletion the vessels of the rest of the body and very greatly intensifies the already existing plethora. If this is not speedily counterbalanced by a free secretion from the udder, kidneys, bowels, and other excretory organs, the most dire results may ensue.

Calving may thus be held to be an exciting cause, and yet the labor and fatigue of the act are not active factors. It is after the easy calving, when there has been little expenditure of muscular or nervous energy and no loss of blood, that the malady is seen. Difficult parturitions may be followed by metritis, but they are rarely connected with parturition fever.

All these factors coincide in intensifying the one condition of plethora and point to that as a most essential cause of the affection. It is needless to enter here into the much-debated question as to the mode in which the plethora brings about the characteristic symptoms and results. As the results show disorder or suspension of the nervous functions mainly, it may suffice to say that this condition of the blood and blood vessels is incompatible with the normal functional activity of the nerve centers. How much is due to congestion of the brain and how much to bloodlessness may well be debated, yet in a closed box like the cranium, in which the absolute contents can not be appreciably increased or diminished, it is evident that, apart from dropsical effusion or inflammatory exudation, there can be only a given amount of blood; therefore, if one portion of the brain is congested, another must be proportionately bloodless; and as congestion of the eyes and head generally and great heat of the head are most prominent features of the disease, congestion of the brain must be accepted. This, of course, implies a lack of blood in certain other parts or blood vessels.

The latest developments of treatment indicate very clearly that the main cause is the production of poisonous, metabolic products (leucomains and toxins) by secreting cells of the follicles of the udder, acting on the susceptible nerve centers of the plethoric, calving cow. Less fatal examples of udder poisons are found in the first milk (colostrum), which is distinctly irritant and purgative, and in the toxic qualities of the first milk drawn from an animal which has been subjected to violent overexertion or excitement. Still more conclusive as to the production of such poisons is the fact that the full distention of the milk ducts and follicles, and the consequent driving of the blood out of the udder and arrest of the formation of depraved products, determines a speedy and complete recovery from the disease. This does not exclude the other causes above named, nor the influence of a reflex nervous derangement proceeding from the udder to the brain.

_Symptoms._--It may be said that there are two extreme types of this disease, with intervening grades. In both forms there is the characteristic plethora and more or less sudden loss of voluntary movement and sensation, indicating a sudden collapse of nervous power; in one, however, there is such prominent evidence of congestion of head and brain that it may be called the congestive form par excellence, without thereby intimating that the torpid form is independent of congestion.

In the congestive form there is sudden dullness, languor, hanging back in the stall, or drooping the head, uneasy movements of the hind limbs or tail; if the cow is moved, she steps unsteadily, or even staggers; she no longer notices her calf or her feed; the eyes appear red and their pupils dilated; the weakness increases and the cow lies down or falls and after that is unable to rise. At this time the pulse is usually full, bounding, and the temperature raised, though not invariably so, the head, horns, and ears being especially hot and the veins of the head full, while the visible mucous membranes of nose and eyes are deeply congested.

The cow may lie on her breastbone with her feet beneath the body and her head turned sleepily round, with the nose resting on the right flank; or, if worse, she may be stretched full on her side, with even the head extended, though at times it is suddenly raised and again dashed back on the ground. At such times the legs, fore and hind, struggle convulsively, evidently through unconscious nervous spasm. By this time the unconsciousness is usually complete; the eyes are glazed, their pupils widely dilated, and their lids are not moved when the ball of the eye is touched with the finger. p.r.i.c.king the skin with a pin also fails to bring any wincing or other response. The pulse, at first from 50 to 70 a minute, becomes weaker and more accelerated as the disease advances. The breathing is quickened, becoming more and more so with the violence of the symptoms, and at first a.s.sociated with moaning (in exceptional cases, bellowing), it may, before death, become slow, deep, sighing, or rattling (stertorous).

The temperature, at first usually raised, tends to become lower as stupor and utter insensibility and coma supervene. The bowels, which may have moved at the onset of the attack, become torpid or completely paralyzed, and, unless in case of improvement, they are not likely to operate again.

Yet this is the result of paralysis and not of induration of the feces, as often shown by the semiliquid, pultaceous condition of the contents after death. The bladder, too, is paralyzed and fails to expel its contents. A free action of either bladder or bowels, or of both, is always a favorable symptom. The urine contains sugar, in quant.i.ty proportionate to the severity of the attack.

In nearly all cases the torpor of the digestive organs results in gastric disorder; the paunch becomes the seat of fermentation, producing gas, which causes it to bloat like a drum. There are frequent eructations of gas and liquid and solid feed, which, reaching the paralyzed throat, pa.s.s in part into the windpipe and cause inflammations of the air pa.s.sages and lungs.

In the torpid form of the disease there is much less indication of fever or violence. There may be no special heat about the horns, ears, or forehead, nor any marked redness or congestion of the eyes or nose, nor engorgement of the veins of the head. The attack comes on more slowly, with apparent weakness of the hind limbs, dullness, drowsiness, suspension of rumination and appet.i.te, and a general indifference to surrounding objects. Soon the cow lies down, or falls and is unable to rise, but for one or two days she may rest on the breastbone and hold the head in the flank without showing any disorderly movements. Meanwhile there is not only loss of muscular power and inability to stand, but also considerable dullness of sensation, p.r.i.c.king the skin producing no quick response, and even touching the edge of the eyelids causing no very prompt winking. Unless she gets relief, however, the case develops all the advanced symptoms of the more violent form, and the animal perishes.

In advanced and fatal cases of either form the insensibility becomes complete; no irritation of skin or eye meets any response; the eye becomes more dull and gla.s.sy; the head rests on the ground or other object; unless prevented the cow lies stretched fully on her side; the pulse is small, rapid, and finally imperceptible; the breathing is slow, deep, stertorous, and the expirations accompanied with puffing is slow, the cheeks, and death comes quietly or with accompanying struggles.

_Prevention._--For such fatal disease prevention is of far more consequence than treatment. Among the most efficient preventives may be named a spare diet (amounting to actual starvation in very plethoric, heavy-milking cows) for a week before calving and at least four days after. A free access to salt and water is most important, as the salt favors drinking and the water serves to dilute the rich and dense blood. Iced water, however, is undesirable, as a chill may favor the onset of fever. A dose of Epsom salt (1 to 2 pounds) should be given 12 to 24 hours before calving is due, so that it may operate at or just before that act. In case calving has occurred unexpectedly in the heavy milker, no time should be lost in giving the purgative thereafter. A most important precaution in the fleshy, plethoric cow, or in one that has been attacked at a previous calving, is to avoid drawing any milk from the bag for 12 or 24 hours after calving.

Breeders on the island of Jersey have found that this alone has almost abolished the mortality from milk fever. If Epsom salt is not at hand, saltpeter (1 ounce) should be used for several days. Daily exercise is also of importance, and, excepting in midsummer, when the heat of the sun may be injurious, the value of open air is unquestionable. Even in summer an open shed or shady grove is incomparably better than a close, stuffy stall. A rich pasture (clover especially), in May, June, or July, when at its best, is to be carefully avoided. It is better to keep the cow indoors on dry straw with plenty of salt and water than to have access to such pastures.

_Treatment._--Treatment of milk fever has been completely revolutionized, with the result that a former mortality of 50 to 70 per cent has been practically abolished. Formerly the most vigorous treatment was practiced by bleeding, purging, the increase of peristalsis by eserin or pilocarpin, enemas, cold in the head, counterirritants, aconite, tartar emetic, sponging, wet-sheet packing, etc. The gross mortality, however, was not materially reduced, and nearly all that were attacked within the first two days after calving perished.

The first step in the modern treatment was made in 1897, when J. Schmidt published his successful treatment by the injection of the teats and milk ducts with a solution of iodid of pota.s.sium (1-1/2 drams to 1 quart of water). This reduced the mortality to 17 per cent. Others followed this lead by the injection of other antiseptics (lysol, creolin, creosol, chinosol, common salt, etherized air, oxygen). These succeeded as well as the iodid solution. With the injection of gases, however, a fuller distention of the udder was usually secured, and virtually every case recovered. This suggested the full distention of the udder with common atmospheric air filtered and sterilized, and this with the most perfect success. With sterile air Schmidt-Kolding claimed 96.7 per cent recoveries in 914 cases.

In America the full distention of the udder, whether with oxygen or filtered air, has proved invariably successful in all kinds of cases, including the violent ones that set in within a few hours after calving. In 1 or 2 hours after the injection the cow has got up, had free pa.s.sages from the bowels and bladder, bright expression of countenance, and some return of appet.i.te. In my cases which had made no response for 8 hours to the iodid injection, the injection of the udder to full repletion with the gas (oxygen or air) has had immediately beneficial results. A similar full distention of the bag with a common-salt solution (0.5 to 100), or even with well-boiled water, is equally effective, but in these cases the weight of the liquid causes dragging upon the udder and a measure of discomfort which is escaped under the treatment with gas.

The value of each method depends on the fullness of distention of the udder and the arrest in larger part of the circulation and chemical changes in its tissues. This distention acts like magic, and seems hardly to admit of failure in securing a successful outcome.

It can not, however, be recommended as absolutely devoid of dangers and serious complications. To get the best results it should be applied only by one who has been trained in the careful antiseptic methods of the bacteriological laboratory. Some readers will recall the case of the injection of the udders of show cows at Toronto to impose upon the judges.

The cows treated in this way had the udders infected and ruined, and several lost their lives. There is no better culture medium for septic and other germs than the first milk (colostrum) charged with alb.u.min and retained in the warm udder. Already in the hands of veterinarians even the Schmidt treatment has produced a small proportion of cases of infective mammitis. How many more such cases will develop if this treatment becomes a popular domestic resort, applied by the dairyman himself in all sorts of surroundings and with little or no antiseptic precautions? Even then, however, the losses will by no means approach the past mortality of 50 to 70 per cent, so that the economy will be immeasurable under even the worst conditions. A fair test and judgment of this treatment, however, can be obtained only when the administrator is trustworthy and painstaking, well acquainted with bacteriological antisepsis and with the general and special pathology of the bovine animal.

The necessary precautions may be summarized as follows:

(1) Provide an elastic rubber ball and tubes furnished with valves to direct the current of air, as in a common Davidson syringe.

(2) Fill the delivery tube for a short distance with cotton sterilized by prolonged heating in a water bath.

(3) In the free end of the delivery tube fit a milking tube to be inserted into the teat.

(4) Sterilize the entire apparatus by boiling for 30 minutes, and, without touching the milking tube, wrap it in a towel that has been sterilized in a water bath or in live steam and dried.

(5) Avoid drawing any milk from the teats; wash them and the udder thoroughly with warm soapsuds; rinse off with well-boiled and cooled water, and apply to the teats, and especially to their tips, a 5 per cent solution of carbolic acid or lysol, taking care that the teats are not allowed to touch any other body from the time they are cleansed until the teat tube is inserted. It is well to rest the cleansed and disinfected udder on a sterilized pad of cotton or a boiled towel.

(6) The injecting apparatus is unwrapped; the teat tube, seized by its attached end and kept from contact with any other body, is inserted into the teat, while an a.s.sistant working the rubber pump fills the quarter as full as it will hold. The tube is now withdrawn and a broad tape is tied around the free end of the teat to prevent escape of the air.

(7) The teat tube, which has been carefully preserved from possible contact with other bodies, is dipped in the carbolic acid solution and inserted in a second teat, and the second quarter is inflated, and so with the third and fourth.

(8) The rec.u.mbent cow is kept resting on her breastbone, with the head elevated, even if it should be necessary to pack around her with straw bundles or to suspend the head by a halter. When lying on her side she is liable to develop fatal bloating and to have belching of gas and liquids, which, pa.s.sing down the windpipe, cause fatal broncho-pneumonia.

(9) If in 2 hours the cow is not on her feet, if there is no brighter or more intelligent expression, if she has pa.s.sed no manure or urine, and if the air has become absorbed, leaving the udder less tense, the injection of the bag may be repeated, under the same scrupulous and rigid precautions as at first. In all cases, but especially in severe ones, it is well to keep watch of the patient, and to repeat the distention on the first indication of relapse. Should there not be a free discharge of feces and urine after rising, indicating a natural resumption of the nervous functions, the case should be all the more carefully watched, so that the treatment may be repeated if necessary.

Accessory treatment may still be used, but is rarely necessary. A dose of purgative medicine (1-1/2 pounds of Epsom salt) in warm water may be given in the early stages, while as yet there is no danger of its pa.s.sing into the lungs through paralysis of the throat. Eserin or pilocarpin (1-1/2 grains) may be given under the skin to stimulate the movements of the bowels. Sponging the skin, and especially the udder, with cool water, may be resorted to in hot weather.

Bloating may demand puncture of the paunch, in the left flank, with a cannula and trocar, the evacuation of the gas, and the introduction through the tube of a tablespoonful of strong liquid ammonia in a quart of cold water or other antiferment.

The economic value of the new treatment of milk fever is enormous. The United States has more than 22,000,000 milk cows. If we could raise their quality by preserving and breeding from the largest producers of both milk and b.u.t.terfat, in place of losing the best by milk fever, as in the past, and if we could thus obtain an average increase of 2 quarts a day, the proceeds at 3 cents a quart would amount to $130,000,000 a year.

PALSY AFTER CALVING (DROPPING AFTER CALVING).

This consists in a more or less complete loss of control of the hind limbs occurring after calving, and caused by low condition, weakness, and exposure to cold or to injurious compression of the nerves of the hind limbs by a large calf pa.s.sing through the pelvis. Its symptoms do not differ from those of palsy of the hind limbs, occurring at other times, and it may be treated in the same way, except so far as bruises of the v.a.g.i.n.a may demand special smoothing treatment.

CONGESTION OF THE UDDER (GARGET).

In heavy milkers, before and just after calving, it is the rule that the mammary gland is enlarged, hot, tense, and tender, and that a slight exudation or pasty swelling extends forward from the gland on the lower surface of the abdomen. This physiological congestion is looked upon as a matter of course, and disappears in two or three days when the secretion of milk has been fully established. This breaking up of the bag may be greatly hastened by the sucking of a hungry calf and the kneading it gives the udder with its nose, by stripping the glands clean thrice daily, and by active rubbing at each milking with the palm of the hand, with or without lard or, better, with camphorated ointment.

The congestion may be at times aggravated by standing in a draft of cold air or by neglect to milk for an entire day or more (overstocking, hefting) with the view of making a great show of udder for purposes of sale. In such cases the surface of the bag pits on pressure, and the milk has a reddish tinge or even streaks of blood, or it is partially or fully clotted and is drawn with difficulty, mixed, it may be, with a yellowish serum (whey) which has separated from the casein. This should be treated like the above, though it may sometimes demand fomentations with warm water to ward off inflammation, and it may be a week before the natural condition of the gland is restored.

INFLAMMATION OF THE UDDER (SIMPLE MAMMITIS).

Congestion may merge into active inflammation, or it may arise direct, in connection with exposure to cold or wet, with standing in a cold draft, with blows on the udder with clubs, stones, horns, or feet, with injury from a sharp or cold stone, or the projecting edge of a board or end of a nail in the floor, with sudden and extreme changes of weather, with overfeeding on rich alb.u.minous feed like cotton seed, beans, or peas, with indigestions, with sores on the teats, or with insufficient stripping of the udder in milking. In the period of full milk the organ is so susceptible that any serious disturbance of the general health is liable to fall upon the udder.

_Symptoms._--The symptoms and mode of onset vary in different cases. When following exposure there is usually a violent shivering fit, with cold horns, ears, tail, and limbs, and general erection of the hair. This is succeeded by a flush of heat (reaction) in which the horns, ears, and limbs become unnaturally warm and the gland swells up and becomes firm and solid in one, two, three, or all four quarters. There is hot dry muzzle, elevated temperature, full, accelerated pulse, and excited breathing, impaired or suspended appet.i.te and rumination, with more or less costiveness, suppression of urine, and a lessened yield of milk, which may be entirely suppressed in the affected quarter.

In other cases the shivering escapes notice, the general disorder of the system is little marked or comes on late, and the first observed sign of illness is the firm swelling, heat, and tenderness of the bag. As the inflammation increases and extends, the hot, tender udder causes the animal to straddle with its hind limbs, and, when walking, to halt on the limb on that side. If the cow lies down it is on the unaffected side. With the increase in intensity and the extension of the inflammation the general fever manifests itself more prominently. In some instances the connective tissue beneath the skin and between the lobules of the gland is affected, then the swelling is uniformly rounded and of nearly the same consistency, pitting everywhere on pressure. In other cases it primarily attacks the secreting tissue of the gland, then the swelling is more localized and appears as hard, nodular ma.s.ses in the interior of the gland. This last is the usual form of inflammation occurring from infection entering by the teats.

In all cases, but especially in the last-named form, the milk is suppressed and replaced by a watery fluid colored with blood (sometimes deeply) and mingled with ma.s.ses of clotted casein. Later it becomes white and purulent, and in many cases of an offensive odor.

The course of the disease is sometimes so rapid and at others so slow that no definite rule can be laid down. In two or three days, or from that to the end of the week, the bag may soften, lose its heat and tenderness, and subside into the healthy condition, even resuming the secretion of milk.

The longer the inflammatory hardness continues the greater the probability that its complete restoration will not be effected. When a portion of the gland fails to be restored in this way, and has its secretion arrested, it usually shrinks to a smaller size. More commonly a greater quant.i.ty of the inflammatory product remains in the gland and develops into a solid, fibrous ma.s.s, causing permanent hardening (induration). In other cases, in place of the product of inflammation developing into a fibrous ma.s.s, it softens and breaks down into white, creamy, liquid pus (abscess). This abscess may make its way to the surface and escape externally, or it may burst into a milk duct and discharge through the teat. It may break into both and establish a channel for the escape of milk (fistula). In the worst types of the disease gangrene may ensue, a quarter or half or even the whole udder, losing its vitality, and sloughing off if the cow can bear up against the depressing influence. These gangrenous cases are probably always the result of infection and sometimes run a very rapidly fatal course. I remember one to which I was called as soon as the owner noticed it, yet I found one-quarter dark blue, cold, and showing a tendency to the formation of blebs containing a b.l.o.o.d.y secretion. The cow, which had waded through a depth of semiliquid manure to reach her stall, died within 24 hours.