Getting ready for Foaling
The ultimate goal of any breeding operation should be both
maximal foaling and a high survival rate of foals. Most mares
will have a normal parturition if left unattended, however, the
value of broodmares and their progeny can make leaving
parturition to nature an expensive gamble. As the value of mares
and foals rise, it becomes more desirable to have someone present
during foaling, allowing for immediate assistance to both mare
and foal if needed.
Being present when a mare foals can be more difficult than
expected. The mare seems to prefer solitude and quiet during
parturition. Observers have noted that 75 to 85 percent of foals
are born between 6 pm and 6 am. Some mares, if continuously
"checked," will delay delivery for several hours or days, until
left in solitude.
Gestation Length
The average gestation length (duration of pregnancy) of mares is
335 to 340 days, but can range from 320 to 370 days. There may be
much variability among mares, but most individually follow
similar patterns year after year. Foals are considered premature
if delivered at less than 326 days of gestation and usually
require immediate veterinary attention. Mares foaling before 310
days are considered to have aborted. Many breeders will calculate
the expected foaling date at 11 months following the last
breeding date. Most mares will gestate longer than 11 months;
however, this allows for fewer "surprise" foalings in undesirable
conditions.
There are various traits which can influence length of a mare's
pregnancy. Studies have shown colts tend to gestate 2 to 7 day
longer than fillies. The nutritional plane of a mare also has
been shown to have some influence on gestation length.
Additionally, mares foaling during the late spring and summer
months (long days) tend to have a shorter gestation length than
those foaling in January or February. Exposure of bred mares to
artificially lengthened days during the latter third of gestation
has been shown to shorten gestational length by about 10 days.
Early Signs
The signs of impending parturition are about as variable as
gestation length. Although there is a tremendous amount of
variation among mares, many individuals do repeat their foaling
behavior year after year. Therefore, it is recommended to keep
accurate records on each mare to aid future deliveries.
The classical signs of approaching parturition include udder
development beginning 2 to 6 weeks before foaling, then milk let
down into the teats (teat distension) 4-6 days prior to
parturition. Due to oozing out of some of the colostrum, the ends
of the teats become covered over and the mare is said to be
"waxing", which occurs 1-2 days before foaling. At this time,
some mares will have occasional dripping or streaming of
colostrum. If this streaming is continuous, the colostrum should
be collected and stored for possible use with the newborn foal.
In addition to changes associated with the mammary gland,
muscular relaxation in the pelvic region occurs progressively
during the last 7-14 days of gestation and the mare
begins to relax during the final days of gestation.
Many mares will show these "classic" signs of approaching
parturition and make it fairly easy to determine their foaling
time. On the other hand some mares will break all the rules and
these signs may not be present, or may appear at varied times.
Predicting Foaling Time-Water Hardness Test
For mares with unknown foaling history, or for mares which are
unpredictable for some reason, there is help available. Several
commercial kits to estimate foaling time have recently come onto
the market. These test kits are based on the fact that in most
mares, calcium and magnesium concentrations in prepartum mammary
secretion rise progressively during the latter portion of
gestation to the time of foaling. A majority of mares show a
significant rise in calcium and magnesium concentration just
prior to parturition. This allows foaling attendants to estimate
time of foaling within 12 to 24 hours.
The kits have been most useful in determining when the mare will
not foal. In other words, if the test shows no changes in the
calcium concentration, the mare probably will not foal within the
next 24 hours, and thus would not need to be watched as closely.
When a rise in calcium is indicated, the foaling attendant could
then direct more attention to the mare which is close to foaling.
These test kits, available from veterinarians, are simple to use
and fairly inexpensive (.25 to $1.00 per test). All kits require
taking 1-4 cc; of milk daily once the classical signs of
approaching parturition are observed. Generally, samples should
be taken for approximately 10 days. Recent research has shown
daily samples collected during the early evening hours were
adequate for detecting the prepartum calcium rise.
Parturition-Stage I
Parturition is typically broken down into three stages. Stage I,
normally lasting 1 to 4 hours, reflects the initial uterine
contractions and final positioning of the foal for delivery.
These contractions will make the mare appear nervous and
uncomfortable. Typically the mare will exhibit the following
behavior:
Restlessness, indicated by frequent interruptions in eating. She
may stop chewing feed already in her mouth or she may pace the
stall.
Pawing the bedding or ground in different places as if looking
for something, and switching her tail.
Getting up and down frequently.
Sweating in the flanks.
Urinating frequently.
These indicators are far from infallible and in some mares, the
appearance of the water bag (the outer membranes surrounding the
foal) may be the first signs of parturition observed.
During this stage, the mare can be prepared for foaling, if
desired. This could include washing the mare's privates and udder
with warm water and wrapping her tail with a clean bandage. If a
veterinarian is readily accessible, this is a good time to notify
them of the approaching parturition so they can be prepared in
the event of any problems.
Parturition-Stage II
Stage II is the most critical time, as this is when the foal
actually appears. If foaling is proceeding normally, the mare
should be left on her own. What is normal? This second stage,
hard labor and foal delivery, is usually completed in 10 to 30
minutes. Close observation, without interference unless
absolutely necessary, is important throughout this stage. Some
mares object to assistance during this time. A viewing window or
video camera system out of the mare's sight is preferred to avoid
disturbing the parturition process.
The mare will experience heavy abdominal contractions and lie
flat on her side. Her water bag will appear and should break on
its own during the first part of Stage II.
Although dystocia (foaling difficulty) is uncommon in mares
(<10%), it is important the foaling attendant be familiar with
both normal and abnormal foal presentations. In a normal
presentation, both front feet with heels down will appear first,
and usually one foot will be slightly ahead of the other (Figure
1). The feet are followed by the nose and head resting between
the knees; the back of the foal is toward the back of the mare.
If this is not what is observed, call a veterinarian immediately.
The foal could suffocate if birth is delayed. If the foal is
delivered, except for the hips and rear legs, gently pulling in a
downward direction toward the mare's heels will usually relieve
this "hip lock".
Following birth, the mare may rest, allowing the foals hind legs
to remain in the birth canal for a period of time before they are
pushed out. Once the foal is born, patience is critical. The
inexperienced horseperson has a tendency to rush into the stall,
causing the mare to stand and prematurely rupture the umbilical
cord. It is important to allow the mare to lie as long as
possible to prevent early cord rupture, as the foal receives
several pints of blood via the umbilicus if left undisturbed.
Stage II ends following birth when the umbilical cord is broken
as the mare stands or foal struggles.
Once the cord is broken, do not tie it off with sutures unless
the foal is bleeding excessively. To avoid infection, dip the
stump of the umbilical cord in 7 percent iodine solution repeat
the process several times during the first few days of life. This
will help prevent bacteria invasion into the body via the navel
stump (navel-ill) which can lead to serious complications, such
as neonatal septicemia and septic arthritis.
Parturition-Stage III
The final stage of parturition, Stage III, is the delivery of the
placenta (afterbirth). These membranes, which surround the foal
during gestation, should be expelled 3 to 4 hours after delivery.
Once expelled, the placenta should be examined to determine if it
is intact or if any portions may have been detached. Placenta
retention can be a problem, leading to uterine infection
(endometritis) and/or laminitis (founder). Under no circumstances
should the placenta be pulled from the mare! Typically, the mare
will stand with the placenta partially expelled while the foal
struggles to stand and nurse.
The foal's nursing helps stimulate uterine contractions, aiding
in placental release. Pulling the placenta could tear or prolapse
the uterus or result in contamination of the uterus with pieces
of torn placenta.
In cases of retained placenta, treatment should be done under
veterinarian supervision. This treatment typically includes
administration of oxytocin to stimulate uterine contractions, and
antibiotics and uterine infusion may be required. Mares which had
a retained placenta may be poor candidates to be bred on foal
heat.
After parturition, mares may experience some mild to moderate
colic as her uterus and reproductive tract contracts and heals.
During the first week postpartum, a reddish-brown discharge may
be present. This discharge is normal. If a white discharge
develops, however, this indicates a uterine infection and a
veterinarian should be consulted for treatment.
Preparations for Foaling-Facilities
A foaling mare should not be placed in a strange environment or
have a stranger act as night attendant immediately prior to
parturition. Any sudden changes may delay foaling. Ideally, mares
should be placed in the foaling environment 2 to 3 weeks prior to
her expected foaling date.
Mares can foal in a variety of locations, depending on the
weather and facilities available. Whatever the choice of foaling
locations, the environment should be clean, have adequate space,
and be reasonably quiet. Mares due to foal in the winter months
will require a large (14' X 14' minimum), clean foaling stall.
During warm weather, many producers choose to allow their mares
to foal in grassy paddocks or pastures. Dirt lots should be
avoided, if possible.
For mares foaling in a stall, the stall should be freshly bedded
with clean, dry straw rather than shavings. An 8- to 10-
inch-thick bed of straw will decrease dust, chances of infection,
and is easier to clean. Safety to the mare and foal should be
kept in mind when selecting a foaling stall. Stalls should be
constructed to allow isolation of the mare and safety to the
newborn foal. Thorough disinfection of the stall prior to
bringing in the mare will help prevent disease. The mare should
be allowed ample exercise up to foaling. Stall confinement for an
extended period just prior to foaling may predispose the mare to
impaction colic and abnormal swelling.
Mares foaling in paddocks or pasture should either be isolated or
have sufficient space to separate themselves from any other
horses in the pasture. Additionally, the pasture/paddock should
be examined for possible hazards to the foal. A shelter should be
provided in case of wet or cold weather.
Regardless of the place, the foaling area should be isolated and
quiet. Safety of the mare and foal should be kept in mind when
deciding where the foaling will occur. The cleanliness of the
foaling area cannot be stressed enough. Foaling in contaminated
areas can predispose the foal to bacteria invasion and neonatal
septicemia via the navel stump.
Preparations for Foaling-Caslicks Removal
Early in gestation, some mares require a Caslicks operation to
partially suture together the lips. Caslicks are
used to prevent problems in mares that have abnormal
conformation. Mares that have a Caslicks must have the lips of
opened at least 30 days prior to foaling. If the
Caslicks is not opened, there is the possibility of oblique tears
which are difficult to repair and may
result in a deformity that leads to uterine infection.
Inducing Parturition?
With the great variability in determining the foaling time in
mares, the question of labor induction frequently arises.
Although it is possible to induce parturition in mares, it is not
recommended. Only in extreme situations, such as a life
threatening condition to the mare or foal or some type of medical
emergency, is parturition induction recommended. If this
procedure is used, it should be done under supervision of an
experienced veterinarian.
A mare improperly induced could result in severe complications
to both the mare and foal.
If conditions warrant a mare to have labor induced, she must only
be induced once certain criteria are met. First, the mare must
have reached a gestation length of at least 330 days. Substantial
mammary development with colostrum present is critical.
Additionally, the cervix must be soft and dilated the width of
one to two fingers. Finally, the foal should be in the correct
position for a "normal" presentation. If these conditions are not
in place, the mare may not be close enough to parturition for a
safe induction.
There are various methods your veterinarian may choose to induce
labor. It is important to remember that induction of parturition
in mares should not be practiced routinely, due to the risks
involved to both mare and foal.
