|
The
Liphook Equine Hospital
FOALING
The expected birth
of a foal from a favourite mare is an exciting but worrying
time for many horse owners. Ideally, help and advice should
be sought from your veterinary surgeon or someone with experience
in foaling mares, in good time before the event. It is most
important to know what is ‘normal’ both in terms
of the foaling process and how to expect the foal to behave
once born.
How should I prepare
my mare for foaling during pregnancy?
Your mare should have
been in good condition throughout her pregnancy. Very poor
or over fat mares often produce small foals. It is wise
to vaccinate the mare against influenza and tetanus approximately
one month prior to foaling as this will boost antibody levels
in her colostrum (first milk) which helps to protect her
foal against infections during its first few weeks of life.
If your mare is to foal away from home, she should be moved
four to six weeks prior to foaling so that she can develop
specific antibodies to potential infections in her new environment.
You should have prepared
a large clean stable which should be ready at any time should
the mare start to foal. Mares should be foaled where they
can be discretely observed and where help can be easily
given if problems arise. In UK this usually means in a stable
environment, although mares can be foaled outside if the
weather is good and they can be clearly observed and helped
if needed. The bed should be of good quality deep straw
or rubber. Shavings are not a good bed for foaling as they
stick to the birth fluids and find their way into foal’s
noses and other places that they should not be. The stable
should be well lit and there should be a readily available
supply of clean warm water. A first aid kit containing scissors,
disinfectant, string, wound powder and towels should be
on hand. Stud farms have cylinders of oxygen with the necessary
control valve and soft rubber tubing in case the foal needs
to be resuscitated and a stock of frozen equine colostrum
and hyperimmune donor plasma in case these are needed to
boost the foal’s immunity.
Foals are born after
11 months gestation (time in the mare’s womb). Thoroughbred
breeders work on an average gestation length of 340 days
to work out their ‘due dates’. Some mares foal
earlier and some later. Foals are not usually viable if
born before 250-300 days. Some older mares and others with
chronic uterine problems sometimes ‘hang on’
to their foals for up to 350 days and, unusually even a
full year. These overdue foals are often poor specimens
with signs of intrauterine growth retardation when eventually
born. It is, in fact, the foal which has ‘coarse control’
over gestation length. Mares have ‘fine control’
and their state of relaxation can determine at what time
of day the foal is born. Most mares foal during the night,
an instinctive means of helping to protect their vulnerable
new-born foals from predators, but this cannot be relied
upon and full term mares should be watched to make sure
that they do not get into difficulty.
In the weeks leading
up to foaling your mare will start producing milk resulting
in gradual enlargement of her udder. This is called ‘bagging-up’.
During the week before or on her foaling day small amounts
of colostrum may ooze from her teats, creating wax-like
droplets which stick to the tip of the teats. This is called
‘waxing up’. It is a sign that foaling is imminent,
although individual mares can vary enormously in their timing.
The ligaments over the pelvis and under the tail head relax
slightly giving a ‘dropped’ appearance to the
hindquarters. During the 24 hours prior to foaling the mare
may appear restless and uncomfortable and may re-arrange
bedding as if ‘nest making’. These are signs
of first stage labour. She should be moved to the foaling
box as soon as it looks as though she is ready to foal.
The key to good management
of foaling is to observe without interfering unnecessarily.
Closed circuit television can be used and can be very helpful
but should not be relied upon. Foaling ‘alarms’
which work on a harness or head collar sensor which detects
sweating or prolonged lying down are available. Some mare
owners have found these to be helpful. Small samples of
early milk can be collected and tested with ‘dip stick’
tests for calcium and electrolyte concentrations to help
determine whether mares are ‘ready for birth’.
More usefully, mares can be examined to confirm that they
are not ‘ready’ which may help to avoid unnecessary
sitting up. However, mares behave very differently as individuals
and from pregnancy to pregnancy and cameras, monitors and
milk tests cannot be relied upon. There is no real substitute
for experienced ‘sitting up’.
What is first stage
labour?
During first stage
labour, where the foal gets itself into the final birth
position in the birth canal and the mare’s cervix
relaxes, the mare will look restless and will get up and
go down several times with abdominal discomfort. The mare
will raise and lower her tail and produce small quantities
of droppings and urine frequently. Most mares sweat but
some do not. This stage may last for several minutes to
several hours and ends when the mare ‘breaks water’,
i.e. the placenta ruptures and allantoic fluid is released.
Placental rupture can be differentiated from urination because
the mare does not straddle in the urinating stance and the
volume of fluid is too large in consideration of the fact
that the mare has already passed small quantities of urine
repeatedly.
Your veterinary surgeon
should be called if your mare is excessively distressed
or is in prolonged, non-productive discomfort. If the placenta
does not rupture, it may appear at the vulva as a red velvety
structure. This is called ‘red bag’ delivery
and is a sign that the normal site of rupture is too thick
and the mare is separating her placenta to expel the foal.
The foal needs the placenta to be attached to the mare’s
uterus at this time to allow oxygen to pass across from
the mare’s blood, i.e. it needs the placenta to ‘breathe’.
If this happens it is important to tear through the ‘red
bag’ placenta immediately or the foal may suffocate.
This is an emergency.
What is second stage
labour?
As soon as the first
water bag ruptures, you should carefully and gently examine
your mare, with a clean hand, to make sure that the foal’s
muzzle and two front feet are appearing at the vulva covered
by a thin white membrane (amnion). The feet are just ahead
of the muzzle and one foot should be just ahead of the other.
The foal can often be seen to move. If the head or one or
both legs are back, or if more than two feet are present,
or if only the foal’s neck or back can be felt, you
should either correct minor misplacements yourself or call
your veterinary surgeon immediately. While you are waiting
for him to arrive, keep the mare up and walking around the
box to prevent straining and impacting the foal in the birth
canal. This will cause less stress for both mare and foal
and the veterinary surgeon will find re-positioning of the
foal much easier. If the mare keeps trying to strain, pull
her tongue out of one side of her mouth. If the mare appears
unable to expel the foal because it appears too big to come
through the birth canal, or if the mare appears to ‘give
up’, you should call your veterinary surgeon without
delay. If you need to help the mare, pull one leg at a time
when the mare strains. If you pull both legs together you
will maximise the width of the foal across the shoulders
and will make passage through the birth canal more difficult
than it should be.
Once the placenta has
ruptured, most mares will lie down for quite rapid delivery
of their foal. With the foal in the normal position foaling
should progress normally. If the mare’s vulva has
been stitched (Caslick’s operation) it will be necessary
to cut it (episiotomy) at this time, when the mare will
usually not notice, to avoid injury. Sharp, long-bladed,
round-ended, bandage-type scissors should be used to cut
a clean straight cut along the scar which shows the line
of previous repair. You should ask your veterinary surgeon
to instruct you in performing this task or, if you do not
feel confident or sufficiently experienced, ask him to perform
the operation ahead of time, when the mare shows that she
is ready to foal within the next few days.
The mare will usually
lie on her side to push and the foal’s forelegs, head,
trunk and hindquarters should be delivered within a few
minutes. The hindlegs may remain in the birth canal until
the mare moves or the foal starts to struggle. The umbilical
cord should rupture naturally at a point of natural constriction
which develops just below the umbilicus. There should be
minimal bleeding unless the cord has broken prematurely.
The cord should only be clamped and cut if it is too thick
to break naturally or if it breaks prematurely and the foal
is haemorrhaging. The umbilical stump should be treated
with disinfectant solution (e.g. 0.5% chlorhexidine or iodine),
spray or powder. The mare will usually turn to see and lick
her foal.
Occasionally, mares
try to foal standing up. If this happens the foal should
be supported as it is born, at the level of the mare’s
vulva, so it does not fall to the ground and while the blood
passes through the umbilical cord from the placenta. When
the cord stops pulsing, it can be broken just outside the
navel and the foal can be laid in the straw.
What is third stage labour?
During this stage from
after the birth of the foal, the uterus contracts, which
can cause the mare discomfort until the placenta is passed.
When the mare stands, the placenta should be tied up into
a ball so that it does not flap around the mare’s
hocks and frighten her, she does not walk on it and tear
it, and so the extra weight will help its gradual separation
from the mare’s uterus (‘cleansing’).
When it drops from the mare it should be checked carefully
to make sure that it is complete and, in particular, that
both horn tips (blind ‘ends’ corresponding to
the tips of the uterine horns) have been expelled and none
has been retained inside the mare.
The placenta is normally
passed within 1 to 4 hours of foaling. If the placenta has
not come away by 8 hours, or the following morning, your
veterinary surgeon should be called. Retained placenta can
result in infection of the uterus, toxaemia, laminitis and
even death of the mare.
What happens after
the mare has foaled?
The mare usually stands
and starts to lick her foal a few minutes after birth. She
may squeal and ‘nicker’ at it and generally
make a fuss over it. This is an important time of instinctive
‘bonding’ and this should not be confused by
unnecessary interference.
If the mare’s
vulva has torn or if she was stitched, she will need to
be re-stitched after foaling, usually during the next day.
Many mares will lie
down again soon after foaling. This may be just to rest
or may be because she is in pain (colic). She may scrape
or roll indicating her discomfort. If this does not pass
within an hour, or gets progressively more severe, this
may indicate complications (uterine artery haemorrhage,
uterine or colonic rupture) and your veterinary surgeon
should be called, without delay.
The foal should make
attempts to stand and suck and should have achieved both
within 4 hours of birth, usually within 1-2 hours. Ask your
veterinary surgeon for his client information hand-out on
the new-born foal.
If both are bright
and well there is no reason why they cannot be turned out
into a small paddock for a few hours next day, providing
the weather is suitable. Exercise is beneficial to help
the mare’s uterus to recover after foaling and to
help the foal to strengthen and its legs to straighten.
|