The average mare will be in foal for 11 months, or 340 days, but this is variable and gestation length can range from 310 to 370 days. However, unlike humans and other species, a mare going over her due date is rarely a cause for concern. Many mares foal up to six weeks after their due date without problems.
Inducing birth in a mare has a relatively high rate of complication and so is generally not undertaken unless some other medical condition is affecting the dam's life. Thankfully, even with a prolonged pregnancy, foals rarely grow too big in the mare to be born naturally.
Compared to other species such as cows, mares have particularly strong contractions, making normal birthing an extremely rapid process. The speed of foaling can cause its own problems because the mare's strong contractions can quickly cause the foal to become stuck in the birth canal, if, for instance, he is holding a knee flexed at the time of birth. As a result, breeders need to be extremely vigilant for signs that the foaling process is beginning.
Signs of foaling
- The udder starts to fill up two to four weeks before foaling.
- Relaxation, softening and lengthening of the vulva and muscle relaxation either side of the tail. This can occur a few days before foaling. The rump either side of the top of the tail is less taut and the vulva appears longer.
- Waxing or beads of colostrum on teats. However, not all mares will wax. Generally, mares will foal within 24 hours of waxing but this period can be longer in some mares. Some run milk from their teats or milk can be seen on the legs.
Colostrum is the mare's first milk. It is rich in antibodies that provide newborn foals protection against infection. Colostrum can be frozen for up to two years and if there are a number of mares on a farm then freezing some as a back-up supply is wise. Remember that thawing colostrum in the microwave will damage the vital immune proteins in the milk and render it useless, so place the container in a water bath no hotter than a baby's bath (37°C) to thaw slowly. Colostrum can be bottle fed using a lamb teat.
There are three stages of labour:
- Stage 1: The mare is restless and may pace around, lying down and getting up. This movement can help get the foal into the correct position for foaling. This stage can last a few hours and ends with the breaking of the waters. Most mares will sweat at this stage.
- Stage 2: Once the waters have broken, the birthing process is underway and the mare cannot turn back. From the time the waters break, delivery should occur within about 30 minutes. The mare will have uterine contractions and abdominal pressing. The amnion, front feet and nose appears. The amnion is the sac that covers the foal and it is milky-white to transparent in colour. The rest of the foal then follows.
The front feet appear first, then the head appears. Some breeders like to check this is the case by introducing a gloved hand with some obstetric lubricant at the time when the waters break or when the feet appear.
Using your hand gently, you should be able to feel the nose coming above the front legs, verifying that the foal is coming the right way. If you find anything other than this -- for example, one leg without the other, a nose without one or both feet or feet without a nose -- you should call your vet immediately.
Another emergency case is what is known as a 'red bag' presentation, whereby the placenta detaches before the foal comes out. This is seen as a red velvety bag instead of the foal's normal amnion (the amnion is sometimes called the white veil). Red bag presentation requires immediate delivery of the foal, so call your vet immediately and follow his/her instructions until he/she arrives.
Some breeders like to help the mare with delivery of a foal, but it must be stressed that the mare's own contractions are usually more than sufficient, and imprudent or excessive pulling by attendants can cause damage to the mare and foal.
Extra pulling should only be undertaken if the mare seems not to be making progress as she strains. Occasionally, older mares can benefit from help if they become excessively tired during labour.
It is normal for one foreleg to be out further than the other, and that situation should be maintained while pulling, because this helps the foal's shoulders to pass through the mare's birth canal.
Attendants should only pull in unison with the mare's own efforts, and relax between contractions to avoid causing internal injury.
Of course, it must be stressed that no interference should be undertaken without cleaning the entire vulval area with soap and warm water, and use of washed or gloved hands can only proceed after copious lubrication with obstetric gel. Your vet will happily supply these items to have in store.
When the foal is delivered, it is a good idea to help clear the amnion and birth fluids from its face to allow it to breathe freely.
In the first 10 minutes or so, there is no need to pull the foal away from the mare. Normally, the foal's hind legs will remain inside the mare for a while, during which time the umbilical cord is still transferring the foal's own blood back along the length of the cord into his body. If the cord breaks quickly, it will bleed profusely.
In a normal foaling, after these few minutes, the cord will naturally snap off a couple of inches from the foal's body as either the mare or foal move away. If the cord bleeds, pinching it with clean fingers for a couple of minutes should stop it. If not, a piece of clean thread can be tied around the cord to stop the bleeding until it can be dealt with by your vet.
The foal's navel should be dipped in dilute antiseptic solution. A 2pc iodine solution, dilute Hibiscrub solution or Savlon solution can be used. Remember that the 10pc iodine solution found on many farms should be diluted 1:5 before use because if it is used neat it can cause irritation.
- Stage 3: This involves the 'cleaning' or delivery of the placenta. This should be no longer than eight hours after foaling. A mare that retains her placenta is in genuine danger of septicaemia and is very prone to developing laminitis. The placenta should be tied in a knot above the mare's hocks to prevent her ripping it by standing on it.
Sue O'Doherty runs her own veterinary practice, Happy Horse Veterinary Clinic, in Co Wicklow, while Jacqueline Yeomans works at the Ratoath Veterinary Clinic in Co Meath. Together, they run a veterinary courses for horse owners, details of which are available at www.horsevetcourse.com