parturition, such as lack of contractile power in the womb, unduly
strong (inflammatory) adhesions between the womb and the fetal
membranes, wrong presentation of the fetus, contracted pelvis (from
fracture or disease of the bones), or disease and induration of the neck
of the womb.
The mere prolongation of gestation does not necessarily entail the death
of the foal; hence the latter has been born alive at the four hundredth
day. Even when the foal has perished putrefaction does not set in unless
the membranes (water bags) have been ruptured and septic bacteria have
been admitted to the interior of the womb. In the latter case a fetid
decomposition advances rapidly, and the mare usually perishes from
poisoning with the putrid matters absorbed.
At the natural period of parturition preparations are apparently made
for that act. The vulva swells and discharges much mucus, the udder
enlarges, the belly becomes more pendent, and the animal strains more or
less. No progress is made, however; there is not even opening of the
neck of the womb, and after a time the symptoms subside. The mare
usually refuses the male, yet there are exceptions to this rule. If the
neck of the womb has been opened and putrefying changes in its contents
have set in, the mare loses appetite and condition, pines, discharges an
offensive matter from the generative passages, and dies of inflammation
of the womb and putrid infection. In other cases there is a slow wearing
out of the strength, and she finally dies of exhaustion.
The treatment is such as will facilitate the expulsion of the fetus and
its membranes and the subsequent washing out of the womb with
disinfectants. So long as the mouth of the womb is closed time should be
allowed for its natural dilatation, but if this does not come about
after a day or two of straining, the opening may be smeared with extract
of belladonna, and the oiled hand, with the fingers and thumb drawn into
the form of a cone, may be inserted by slow oscillating movements into
the interior of the womb. The water bags may now be ruptured, any
malpresentation rectified (see "Difficult parturition"), and delivery
effected. After removal of the membranes wash out the womb first with
tepid water and then with a solution of 2 ounces of borax in half a
gallon of water.
This injection may have to be repeated if a discharge sets in. The same
course may be pursued even after prolonged retention. If the soft parts
of the fetus have been absorbed and the bones only left, these must be
carefully sought for and removed, and subsequent daily injections will
be required for some time. In such cases, too, a course of iron tonics
(sulphate of iron, 2 drams daily) will be highly beneficial in restoring
health and vigor.
ABORTION.
Abortion is, strictly speaking, the expulsion of the impregnated ovum at
any period from the date of impregnation until the foal can survive out
of the womb. If the foal is advanced enough to live, it is premature
parturition, and in the mare this may occur as early as the tenth month
(three hundredth day).
The mare may abort by reason of almost any cause that very profoundly
disturbs the system; hence, very violent inflammations of important
internal organs (bowels, kidneys, bladder, lungs) may induce abortion.
Profuse diarrhea, whether occurring from the reckless use of purgatives,
the consumption of irritants in the feed, or a simple indigestion, is an
effective cause. No less so is acute indigestion with evolution of gas
in the intestines (bloating). The presence of stone in the kidneys,
uterus, bladder, or urethra may induce so much sympathetic disorder in
the womb as to induce abortion. In exceptional cases wherein mares come
in heat during gestation, service by the stallion may cause abortion.
Blows or pressure on the abdomen, rapid driving or riding of the
pregnant mare, especially if she is soft and out of condition from
idleness, the brutal use of the spur or whip, and the jolting and
straining of travel by rail or boat are prolific causes. Bleeding the
pregnant mare, a painful surgical operation, and the throwing and
constraint resorted to for an operation are other causes. Traveling on
heavy, muddy roads, slips and falls on ice, and jumping must be added.
The stimulation of the abdominal organs by a full drink of iced water
may precipitate a miscarriage, as may exposure to a cold rainstorm or a
very cold night after a warm day. Irritant poisons that act on the
urinary or generative organs, such as Spanish flies, rue, savin, tansy,
cotton-root bark, ergot of rye or other grasses, the smut of maize and
other grain, and various fungi in musty fodder are additional causes.
Frosted or indigestible feed, and, above all, green succulent vegetables
in a frozen state, have proved effective factors, and filthy, stagnant
water is dangerous. Low condition in the dam and plethora have in
opposite ways caused abortion, and hot, relaxing stables and lack of
exercise strongly conduce to it. The exhaustion of the sire by too
frequent service, entailing debility of the offspring and disease of the
fetus or of its envelopes, must be recognized as a further cause.
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 papillae, 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
ecraseur, 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.