Special Report on Diseases of the Horse

Chapter 22

Chapter 224,039 wordsPublic domain

The symptoms vary mainly according as the abortion is early or late in pregnancy. In the first month or two of pregnancy the mare may miscarry without observable symptoms, and the fact appears only by her coming in heat. If more closely observed a small clot of blood may be found behind her, in which a careful search reveals the rudiments of the foal. If the occurrence is somewhat later in gestation, there will be some general disturbance, loss of appetite, neighing, and straining, and the small body of the fetus is expelled, enveloped in its membranes. Abortions during the later stages of pregnancy are attended with greater constitutional disturbance, and the process resembles normal parturition, with the aggravation that more effort and straining is requisite to force the fetus through the comparatively undilatable mouth of the womb. There is the swelling of the vulva, with mucus or even bloody discharge; the abdomen droops, the flanks fall in, the udder fills, the mare looks at her flanks, paws with the fore feet and kicks with the hind, switches the tail, moves around uneasily, lies down and rises, strains, and, as in natural foaling, expels first mucus and blood, then the waters, and finally the fetus. This may occupy an hour or two, or it may be prolonged for a day or more, the symptoms subsiding for a time, only to reappear with renewed energy. If there is malpresentation of the fetus it will hinder progress until rectified, as in difficult parturition. Abortion may also be followed by the same accidents, as flooding, retention of the placenta, and leucorrhea.

The most important object in an impending abortion is to recognize it at as early a stage as possible, so that it may, if possible, be cut short and prevented. Any general, indefinable illness in a pregnant mare should lead to a close examination of the vulva as regards swelling, vascularity of its mucous membrane, and profuse mucus secretion, and, above all, any streak or staining of blood; also the condition of the udder, if that is congested and swollen. Any such indication, with colicky pains, straining, however little, and active movement of the fetus or entire absence of movement, are suggestive symptoms and should be duly counteracted.

The changes in the vulva and udder, with a soiled and bloody condition of the tail, may suggest an abortion already accomplished, and the examination with the hand in the vagina may detect the mouth of the womb soft and dilatable and the interior of the organ slightly filled with a bloody liquid.

_Treatment_ should be preventive if possible, and would embrace the avoidance of all causes mentioned, and particularly of such as may seem to be particularly operative in the particular case. If abortions have already occurred in a stud, the especial cause in the matter of feed, water, exposure to injuries, overwork, lack of exercise, etc., may often be identified and removed. A most important point is to avoid all causes of constipation, diarrhea, indigestion, bloating, violent purgatives, diuretics or other potent medicines, painful operations, and slippery roads, unless well frosted.

When abortion is imminent, the mare should be placed alone in a roomy, dark, quiet stall, and have the straining checked by some sedative. Laudanum is usually at hand and may be given in doses of 1 or 2 ounces, according to size, and repeated after two or three hours, and even daily if necessary. Chloroform or chloral hydrate, 3 drams, may be substituted if more convenient. These should be given in a pint or quart of water, to avoid burning the mouth and throat. Or _Viburnum prunifolium_ (black haw), 1 ounce, may be given and repeated if necessary to prevent straining.

When all measures fail and miscarriage proceeds, all that can be done is to assist in the removal of the fetus and its membranes, as in ordinary parturition. As in the case of retention of the fetus, it may be necessary after delivery to employ antiseptic injections into the womb to counteract putrid fermentation. This, however, is less necessary in the mare than in the cow, in which the prevalent contagious abortion must be counteracted by the persistent local use of antiseptics. After abortion a careful hygiene is demanded, especially in the matter of pure air and easily digestible feed. The mare should not be served again for a month or longer, and in no case until after all discharge from the vulva has ceased.

INFECTIOUS ABORTION IN MARES.

This disease is discussed in the chapter on "Infectious Diseases."

PARTURITION.

SYMPTOMS OF PARTURITION.

As the period of parturition approaches, the swelling of the udder bespeaks the coming event, the engorgement in exceptional cases extending forward on the lower surface of the abdomen and even into the hind limbs. For about a week a serous fluid oozes from the teat and concretes as a yellow, waxlike mass around its orifice. About 24 hours before the birth this gives place to a whitish, milky liquid, which falls upon and mats the hairs on the inner sides of the legs. Another symptom is enlargement of the vulva, with redness of its lining membrane, and the escape of glairy mucus. The belly droops, the flanks fall in, and the loins may even become depressed. Finally the mare becomes uneasy, stops feeding, looks anxious, whisks her tail, and may lie down and rise again. In many mares this is not repeated, but they remain down; violent contractions of the abdominal muscles ensue; after two or three pains the water bags appear and burst, followed by the fore feet of the foal, with the nose between the knees, and by a few more throes the fetus is expelled. In other cases the act is accomplished standing. The whole act may not occupy more than 5 or 10 minutes. This, together with the disposition of the mare to avoid observation, renders the act one that is rarely seen by the attendants.

The navel string, which connects the foal to the membranes, is ruptured when the fetus falls to the ground, or when the mare rises, if she has been down, and the membranes are expelled a few minutes later.

NATURAL PRESENTATION.

When there is a single foal, the common and desirable presentation is with the fore feet first, the nose between the knees, and with the front of the hoofs and knees and the forehead directed upward toward the anus, tail, and croup. (Plate XII, fig. 1.) In this way the natural curvature of the body of the fetus corresponds to the curve of the womb and genital passages, and particularly of the bony pelvis, and the foal passes with much greater ease than if placed with its back downward toward the udder. When there is a twin birth the second foal usually comes with its hind feet first, and the backs of the legs, the points of the hocks, and the tail and croup are turned upward toward the anus and tail of the mare. (Plate XII, fig. 2.) In this way, even with a posterior presentation, the curvature of the body of the foal still corresponds to that of the passages, and its expulsion may be quite as easy as in anterior presentation. Any presentation aside from these two may be said to be abnormal and will be considered under "Difficult parturition."

PREMATURE LABOR PAINS.

These may be brought on by, any violent exertion, use under the saddle, or in heavy draft, or in rapid paces, or in travel by rail or sea, blows, kicks, crushing by other animals in a doorway or gate. Excessive action of purgative or diuretic agents, or of agents that irritate the bowels or kidneys, like arsenic, paris green, all caustic salts and acids, and acrid and narcotico-acrid vegetables, is equally injurious. Finally, the ingestion of agents that stimulate the action of the gravid womb (ergot of rye or of other grasses, smut, various fungi of fodders, rue, savin, cotton root, etc.) may bring on labor pains prematurely.

Besides the knowledge that parturition is not yet due, there will be less enlargement, redness, and swelling of the vulva, less mucous discharge, less filling of the udder, and fewer appearances of wax and probably none of milk from the ends of the teats. The oiled hand introduced into the vulva will not enter with the ease usual at full term, and the neck of the womb will be felt not only closed, but with its projecting papillæ, through which it is perforated, not yet flattened down and effaced, as at full term. The symptoms are, indeed, those of threatened abortion, but at such an advanced stage of gestation as is compatible with the survival of the offspring.

_Treatment._--The treatment consists in the separation of the mare, in a quiet, dark, secluded place, from all other animals, and the free use of antispasmodics and anodynes. Opium in dram doses every two hours, or laudanum in ounce doses at similar intervals, will often suffice. When the more urgent symptoms have subsided these doses may be repeated thrice a day till all excitement passes off or until the passages have become relaxed and prepared for parturition. _Viburnum prunifolium_ (black haw), in ounce doses, may be added if necessary. Should parturition become inevitable, it may be favored and any necessary assistance furnished.

DIFFICULT PARTURITION.

With natural presentation this is a rare occurrence. The great length of the fore limbs and face entail, in the anterior presentation, the formation of a long cone, which dilates and glides through the passages with comparative ease. Even with the hind feet first a similar conical form is presented, and the process is rendered easy and quick. Difficulty and danger arise mainly from the act being brought on prematurely before the passages are sufficiently dilated, from narrowing of the pelvic bones or other mechanical obstruction in the passages, from monstrous distortions or duplications in the fetus, or from the turning back of one of the members so that the elongated conical or wedge-shaped outline is done away with. Prompt as is the normal parturition in the mare, however, difficult and delayed parturitions are surrounded by special dangers and require unusual precautions and skill. From the proclivity of the mare to unhealthy inflammations of the peritoneum and other abdominal organs, penetrating wounds of the womb or vagina are liable to prove fatal. The contractions of the womb and abdominal walls are so powerful as to exhaust and benumb the arm of the assistant and to endanger penetrating wounds of the genital organs. By reason of the looser connection of the fetal membranes with the womb, as compared with those of ruminants, the violent throes early detach these membranes throughout their whole extent, and the foal, being thus separated from the mother and thrown on its own resources, dies at an early stage of any protracted parturition. The foal rarely survives four hours after the onset of parturient throes. From the great length of the limbs and neck of the foal it is extremely difficult to secure and bring up limb or head which has been turned back when it should have been presented. When assistance must be rendered, the operator should don a thick woolen undershirt with the sleeves cut out at the shoulders. This protects the body and leaves the whole arm free for manipulation. Before inserting the arm it should be smeared with lard. This protects the skin against septic infection and favors the introduction of the hand and arm. The hand should be inserted with the thumb and fingers drawn together like a cone. Whether standing or lying, the mare should be turned with head downhill and hind parts raised as much as possible. The contents of the abdomen gravitating forward leave much more room for manipulation. Whatever part of the foal is presented (head, foot) should be secured with a cord and running noose before it is pushed back to search for the other missing parts. Even if a missing part is reached, no attempt should be made to bring it up during a labor pain. Pinching the back will sometimes check the pains and allow the operator to secure and bring up the missing member. In intractable cases a large dose of chloral hydrate (1 ounce in a quart of water) or the inhalation of chloroform and air (equal proportions) to insensibility may secure a respite, during which the missing members may be replaced. If the waters have been discharged and the mucus dried up, the genital passages and body of the fetus should be lubricated with lard or oil before any attempt at extraction is made. When the missing member has been brought up into position and presentation has been rendered natural, traction on the fetus must be made only during a labor pain. If a mare is inclined to kick, it may be necessary to apply hobbles to protect the operator.

DIFFICULT PARTURITION FROM NARROW PELVIS.--A disproportion between the fetus got by a large stallion and the pelvis of a small dam is a serious obstacle to parturition, sometimes seen in the mare. This is not the rule, however, as the foal up to birth usually accommodates itself to the size of the dam, as illustrated in the successful crossing of Percheron stallions on mustang mares. If the disproportion is too great the only resort is embryotomy.

FRACTURED HIP BONES.--More commonly the obstruction comes from distortion and narrowing of the pelvis as the result of fractures. (Plate XIII, fig. 2.) Fractures at any point of the lateral wall or floor of the pelvis are repaired with the formation of an extensive bony deposit bulging into the passage of the pelvis. The displacement of the ends of the broken bone is another cause of constriction, and between the two conditions the passage of the fetus may be rendered impossible without embryotomy. Fracture of the sacrum (the continuation of the backbone forming the croup) leads to the depression of the posterior part of that bone in the roof of the pelvis and the narrowing of the passage from above downward by a bony ridge presenting its sharp edge forward.

In all cases in which there has been injury to the bones of the pelvis the obvious precaution is to withhold the mare from breeding and to use her for work only.

If a mare with a pelvis thus narrowed has got in foal inadvertently, abortion may be induced in the early months of gestation by slowly introducing the oiled finger through the neck of the womb and following this by the other fingers until the whole hand has been introduced. Then the water bags may be broken, and with the escape of the liquid the womb will contract on the solid fetus and labor pains will ensue. The fetus being small will pass easily.

TUMORS IN THE VAGINA AND PELVIS.--Tumors of various kinds may form in the vagina or elsewhere within the pelvis, and when large enough will obstruct or prevent the passage of the fetus. Gray mares, which are so subject to black pigment tumors (melanosis) on the tail, anus, and vulva, are the most liable to suffer from this. Still more rarely the wall of the vagina becomes relaxed, and being pressed by a mass of intestines will protrude through the lips of the vulva as a hernial sac, containing a part of the bowels. If a tumor is small it may only retard and not absolutely prevent parturition. A hernial protrusion of the wall of the vagina may be pressed back and emptied, so that the body of the fetus engaging in the passage may find no further obstacle. When a tumor is too large to allow delivery the only resort is to remove it, but before proceeding it must be clearly made out that the obstruction is a mass of diseased tissue, and not a sac containing intestines. If the tumor hangs by a neck it can usually be most safely removed by the écraseur, the chain being passed around the pedicel and gradually tightened until that is torn through.

HERNIA OF THE WOMB.--The rupture of the musculo-fibrous floor of the belly and the escape of the gravid womb into a sac formed by the peritoneum and skin hanging toward the ground is described by all veterinary obstetricians, yet it is very rarely seen in the mare. The form of the fetus can be felt through the walls of the sac, so that it is easy to recognize the condition. Its cause is usually external violence, though it may start from an umbilical hernia. When the period of parturition arrives, the first effort should be to return the fetus within the proper abdominal cavity, and this can sometimes be accomplished with the aid of a stout blanket gradually tightened around the belly. This failing, the mare may be placed on her side or back and gravitation brought to the aid of manipulation in effecting the return. Even after the hernia has been reduced the relaxed state of the womb and abdominal walls may serve to hinder parturition, in which case the oiled hand must be introduced through the vagina, the fetus brought into position, and traction coincident with the labor pains employed to produce delivery.

TWISTING OF THE NECK OF THE WOMB.--This condition is very uncommon in the mare, though occasionally seen in the cow, owing to the greater laxity of the broad ligaments of the womb in that animal. It consists in a revolution of the womb on its own axis, so that its right or left side will be turned upward (quarter revolution), or the lower surface may be turned upward and the upper surface downward (half revolution). The effect is to throw the narrow neck of the womb into a series of spiral folds, turning in the direction in which the womb has revolved, closing the neck and rendering distention and dilatation impossible.

The period and pains of parturition arrive, but in spite of continued efforts no progress is made, neither water bags nor liquids appearing. The oiled hand introduced into the closed neck of the womb will readily detect the spiral direction of the folds on its inner surface.

The method of relief which I have successfully adopted in the cow may be equally effective in the mare. The dam is placed (with her head uphill) on her right side if the upper folds of the spiral turn toward the right, and on her left side if they turn toward the left, and the oiled hand is introduced through the neck of the womb and a limb or other part of the body of the fetus is seized and pressed against the wall of the womb, while two or three assistants turn the animal over on her back toward the other side. The object is to keep the womb stationary while the animal is rolling. If success attends the effort, the constriction around the arm is suddenly relaxed, the spiral folds are effaced, and the water bags and fetus press forward into the passage. If the first attempt does not succeed, it may be repeated again and again until success crowns the effort. Among my occasional causes of failure have been the prior death and decomposition of the fetus, with the extrication of gas and overdistention of the womb, and the supervention of inflammation and inflammatory exudation around the neck of the womb, which hinders untwisting. The first of these conditions occurs early in the horse from the detachment of the fetal membranes from the wall of the womb; and as the mare is more subject to fatal peritonitis than the cow, it may be concluded that both these sources of failure are more probable in the former subject.

When the case is intractable, though the hand may be easily introduced, the instrument shown in Plate XIV, figure 7, may be used. Each hole at the small end of the instrument has passed through it a stout cord with a running noose, to be passed around two feet or other portion of the fetus which it may be possible to reach. The cords are then drawn tight and fixed around the handle of the instrument; then, by using the cross handle as a lever, the fetus and womb may be rotated in a direction opposite to that causing the obstruction. During this process the hand must be introduced to feel when the twist has been undone. This method may be supplemented, if necessary, by rolling the mare as described above.

EFFUSION OF BLOOD IN THE VAGINAL WALLS.--This is common as a result of difficult parturition, but it may occur from local injury before that act, and may seriously interfere with it. This condition is easily recognized by the soft, doughy swelling so characteristic of blood clots, and by the dark-red color of the mucous membrane. I have laid open such swellings with the knife as late as 10 days before parturition, evacuated the clots, and dressed the wound daily with an astringent lotion (sulphate of zinc 1 dram, carbolic acid 1 dram, water 1 quart). A similar resort might be had, if necessary, during parturition.

CALCULUS (STONE) AND TUMOR IN THE BLADDER.--The pressure upon the bladder containing a stone or a tumor may prove so painful that the mare will voluntarily suppress the labor pains. Examination of the bladder with the finger introduced through the urethra will detect the offending agent. A stone should be extracted with forceps. (See "Lithotomy.") The large papillary tumors which I have met with in the mare's bladder have been invariably delicate in texture and could be removed piecemeal by forceps. Fortunately, mares affected in this way rarely breed.

FECAL IMPACTION OF THE RECTUM.--In some animals, with more or less paralysis or weakness of the tail and rectum, the rectum may become so impacted with solid feces that the mare is unable to discharge them, and the accumulation both by reason of the mechanical obstruction and the pain caused by pressure upon it will impel the animal to cut short all labor pains. The rounded swelling surrounding the anus will at once suggest the condition, when the obstruction may be removed by the well-oiled or well-soaped hand.

SPASM OF THE NECK OF THE WOMB.--This occurs in the mare of specially excitable temperament, or under particular causes of irritation, local or general. Labor pains, though continuing for some time, produce no dilatation of the neck of the womb, which will be found firmly closed so as to admit but one or two fingers; this, although the projection at the mouth of the womb may have been entirely effaced, so that a simple round opening is left, with rigid margins.

The simplest treatment consists in smearing this part with solid extract of belladonna, and after an interval inserting the hand with fingers and thumb drawn into the form of a cone, rupturing the membranes and bringing the fetus into position for extraction, as advised under "Prolonged retention of the fetus." Another mode is to insert through the neck of the womb an ovoid rubber bag, empty, and furnished with an elastic tube 12 feet long. Carry the free end of this tube upward to a height of 8, 10, or 12 feet, insert a filler into it, and proceed to distend the bag with tepid or warm water.

FIBROUS BANDS CONSTRICTING OR CROSSING THE NECK OF THE WOMB.--These, occurring as the result of disease, have been several times observed in the mare. They may exist in the cavity of the abdomen and compress and obstruct the neck of the womb, or they may extend from side to side of the vagina across and just behind the neck of the womb. In the latter position they may be felt and quickly remedied by cutting them across. In the abdomen they can be reached only by incision, and two alternatives are presented: (1) To perform embryotomy and extract the fetus piecemeal, and (2) to make an incision into the abdomen and extract by the Cæsarean operation, or simply to cut the constricting band and attempt delivery by the usual channel.