Unfortunately, it is occasionally necessary to try to foster a foal
onto a mare that is not its natural mother. This may be for any one of
a number of reasons. The common ones are:-
- For mares who are ill or die at or soon after foaling.
- For mares who have a history of savaging their foals.
- For mares who need to be transported for long distances for mating
or competition and where the owner/manager does not want the foal to
travel with her.
- When foals have been ill soon after birth and separated from their
mare for treatment, the mare may no longer produce milk and/or may lose
interest in her foal.
- The mare may not produce enough milk to feed her foal, either due
to her age, some illness or problems with her mammary glands.
Choice of foster mare
Any mare that is to be used as a foster mare must be of a suitable temperament
i.e. relatively quiet, well handled and a good mother who is unlikely
to harm her new foal, once bonded. She must also be able to produce the
volume of milk necessary to nourish and encourage the normal growth of
her new foal. Draft cross mares make particularly good foster mares because
of their calm temperament and the volume of milk that they usually produce.
The foster mare must be disease free and preferably vaccinated against
tetanus and equine influenza and equine herpes viruses. Even when a foster
mare is required following an emergency, when speed is of the essence,
the risks of introducing infectious disease must be considered and assessed,
in order to protect other horses.
In most cases, a mare only becomes available for use as a foster mare
if she loses her own foal. Such a mare may be ‘advertised’
in the racing media, or though contacts in Clyde Vet Group Equine
Hospital. The National Foaling Bank and other organizations may
be able to ‘hire’ a suitable foster mare until the foal is
weaned (web page in our links section). In some circumstances, such organizations
may accept your foal in order to achieve the fostering process, or may
send an experienced groom with a foster mare to stay at your premises
until the foal is fostered successfully.
Foals for fostering should ideally be less than 3 weeks of age as they
are more difficult to foster after this time. All foals are born without
natural protection against infection. If a newborn foal is to be fostered
it is essential that it receives colostrum either from its own dam or
from a donor source within the first 24 hours of its life. If it is not
possible to obtain colostrum the foal should receive a plasma transfusion
from a suitable donor, discuss with a member of the Clyde Vet Group Equine
Hospital team first. For fostering to be successful, the foal must be
strong and well enough to stand and nurse unassisted. It must be able
to suck vigorously before any attempt at fostering is made.
Preparing the mare and foal for introduction
If the mare has lost her own foal at or near foaling ask if it is possible
to have her own placenta, as this may be useful during the fostering process.
The mare should be left in the box with the dead foal. It was once common
practice to skin the dead foal and to use the skin as a ‘coat’
for the foal to be fostered. Once the bereaved mare is quiet and calm,
the dead foal should be removed and replaced with the foal to be fostered.
Ideally there should be two or three capable people assisting a fostering
process. The mare should be deeply sedated and held in a bridle by a competent
handler. Many people apply a strong smelling ointment (such as Vicks Vaporub)
to the mare’s nostrils to mask the smell of the foal, but this is
not always helpful or necessary, depending upon the response of the individual
mare. A twitch should be available in case it is needed. The mare’s
udder should be clean and full of milk but not tight or painful otherwise
she may resent the foal’s approaches. The foal should be made hungry
by withholding milk for a couple of hours prior to introduction, but not
weak by excessive withholding of food. Where possible its own smell should
be masked by rubbing its coat with the foster mare’s own placenta
or by fitting it with a clean foal rug.
The introduction should be made in a relatively large, clean stable. The
mare is held firmly and confidently with her hindquarters in a corner
and the foal is introduced to her at the level of her shoulders, keeping
the foal and handlers away from her back legs. The foal should be held
so that the mare can see and sniff the new foal. The mare’s reaction
is monitored closely. If very fortunate, her response will be to call
and ‘talk’ to the foal immediately as though it was her own,
suggesting that she will readily accept the orphan foal. More commonly,
mares behave unpredictably and aggressively, attempting to bite, strike
and/or kick at the foal. The mare must be clearly reprimanded for showing
this type of behaviour. In such cases it may be necessary to apply the
twitch, hold a front limb up or pinch a fold of skin just in front of
the shoulder to see if this will distract the mare enough to allow the
foal to approach her more closely. The foal must not be put at risk and
it must not be left unattended at this stage as initial apparent acceptance
may ‘wear off’. Some mares may be ‘intelligent’
enough to wait patiently for an unguarded opportunity to show aggression.
Even where fostering is successful it can take many hours and even days
for the mare to fully accept the foal. The foal is usually happy to suck
but will soon be discouraged if the mare behaves aggressively towards
it or will not allow it to suck. At this stage it is useful to let the
foal wander around in the stable slightly away from the mare so that she
can see it and get used to its presence in her box. If the foal wishes
to lie down, let it do so but at a safe distance from the mare. Every
now and then encourage the foal to approach the mare and attempt to suck.
If the mare remains aggressive towards the foal in spite of combinations
of sedation, twitch, voice and other restraint, it is not worth persevering
and it will be necessary to try to obtain an alternative foster mare.
It may take only a few minutes or sometimes many hours or days to be sure
that a fostering has been successful. Once the foal is sucking and moving
freely around the stable without the mare threatening it or preferable
with her calling and apparently accepting it as her own foal, sedation
can be discontinued. Do not leave the mare and foal alone together until
you are totally confident that acceptance is complete.
Mare milk replacer must be available for use where the fostering process
is going slowly, in order to provide the foal with essential nourishment
and fluids to maintain strength whilst not abolishing hunger and the desire
to suck. Because this is not readily available from tack and feed
shops we try to always have some in stock at Clyde Vet Group Equine Hospital.
We also try to have milk pellets available.
Fostering can be a very successful and satisfying exercise. Most mares
make natural mothers and it is always nice to see a mare that has lost
her own foal accepting another mare’s foal. Orphaned foals that
are raised on foster mares are easier to manage, healthier and better
developed both physically and mentally than hand-reared foals. Hand-reared
foals seldom thrive and usually lack social development. However, if there
is serious risk of injury to the foal during an attempt at fostering,
or if a foster mare is not available, hand rearing may be the only option.
If you wish to discuss fostering further please ring the Hospital 01555
The material contained in this website is presented for information purposes
only . The material is in no way intended to replace professional veterinary
care or attention from a professional veterinary surgeon.
The advice given in any of our web pages cannot be used as the basis
for a diagnosis or choice of treatment.
Clyde Vet Group advises that you should always consult a veterinary surgeon
about any queries with animals under your care.