Foaling the Mare

04th December 2017

Preparation for Foaling

Aim to increase the level of nutrition in the last 3 months of pregnancy. A brood mare should not be allowed to become too thin or too fat. The diet for the last stages of pregnancy should be a proprietary brood mare diet; this will include the correct balance of minerals and nutrients for foal development. Follow the manufacturer’s guidelines initially then feed by eye resulting in a gradual increase in weight prior to foaling, if the mare is getting too fat chaff with balancers can be fed.

It is usual to remove the mare’s shoes when foaling becomes imminent, to lessen the damaged caused if the mare stands on the foal. Some mares may become foot-sore without shoes; take veterinary or your farrier’s advice. It is important to maintain hoof health with regular trims.

Ideally your mare should be following a worming program recommended by your vet. In the last month before foaling your mare should be wormed with an ivermectin product.

Influenza and tetanus vaccination status should be up to date (ie. FT1, FT2 between 21 and 92 days later, FT3 between 150 and 215 days later, then annual boosters). The mare should be given a booster vaccination within the last month of pregnancy, to boost the level of flu and tetanus antibodies in the colostrum for the foal.

Vaccination to reduce the risk of abortion caused by Equine Herpes Virus 1 (EHV1) can be performed at 5, 7 and 9 months of pregnancy. Mares at risk of EHV1 abortion are those at yards where horses are coming and going and thus may bring in infection, in the respiratory form. If you are sending your mare away to foal, the stud may require your mare to be vaccinated against EHV1.

Vaccination to increase the foal’s colostrum derived immunity to diarrhoea caused by Rotavirus infection can be performed at 8, 9 and 10 months of pregnancy.

If your mare is going to foal down or to be covered after foaling at a stud, there may be requirements to have her swabbed for Contagious Equine Metritis (CEM) and to have a blood sample taken to test for Equine Viral Arteritis (EVA) and also Equine Infectious Anaemia (EIA).
Some mares require their vulva to be stitched (Caslicked) in order for them to conceive, this is because air and bacteria are sucked into the vagina as a result of a poor vulval seal. Prior to foaling it is essentially that the Caslicks is reversed in order to prevent tearing of the vulva and anus as the foal is born. This is typically done when the mare starts to show significant signs of mammary gland development. Some mares such as maiden mares give little warning of imminent foaling as such it is better to have the Caslicks reversed sooner rather than leaving it to the last minute.

Once your mare is in foal it is important that the last few months of the pregnancy are well planned. The length of pregnancy in mares is highly variable (330 to 370 days), a rule of thumb is that the due date is 11 months plus 1 week from the last covering date. Mares can be foaled out in a paddock, particularly if the weather is likely to be good at the time of foaling. Most mares foal at night and as such a stable environment may be preferable as this allows ease of observation. If the mare is to foal in a paddock then a suitable stable should be available in the event of a complication.

The stable should be secure and as clean as possible with a comfortable straw bed. Good lighting and clean water should be available. Ideally a small well fenced nursery paddock, close to the stable should be provided for turn out during the first few days and weeks of the foal’s life. The paddock should be clean and level, without any hazards, and preferably rested prior to foaling.

Ideally mares should be moved to their foaling site at least a month before foaling. This will minimise any stress and will allow the mare’s immune system to respond to any pathogens in the new environment. Hopefully this new specific immunity will be passed on to the foal in the colostrum.

Mare Monitoring
Most mares foal without complication, however it is important that they are monitored regularly as the foaling becomes imminent. Mares prefer to foal when all is quiet, as such it is important that the checks do not disturb them. The stable can be fitted with a low wattage light bulb that can be left on. Small cameras are available so that foaling mares can be observed from a distance and sweat and vulva alarms can be used to indicate an imminent labour. In high-risk mares with complications, the milk secretions can be monitored to more accurately identify when labour is likely to begin. Ideally check your mare every couple of hours, by doing this you will note subtle changes that will indicate imminent labour and when you do that is the time to keep a constant eye on her.

Signs of Impending Foaling
The mare herself will start to show signs impending foaling. These may occur several weeks before foaling or may start much closer. The signs include development of the udder, swelling in front of the udder, slackening of the pelvic ligaments resulting in hollowing and softening of the quarters, lengthening and relaxation of the vulva, changes in temperament and the production of wax on the teats. The “waxing-up” of the mare is one of the last signs to occur.

During the last month of pregnancy the udder produces the first milk, colostrum, this is rich in antibodies that protect the foal from infection. Prior to foaling some mares drip or run milk and as a result lose the valuable colostrum, once lost it is not replaced. If this occurs 200ml volumes can be milked from the mare and frozen, this stored colostrum can be thawed in warm water (not microwaved) and bottle-fed to the foal in the first 6 hours after foaling.

There are milk test kits that are available, these are quite accurate at indicating when labour is likely to occur, they can give you the confidence to leave a mare unchecked for a while to allow you to do other things.

The three stages of labour
While a mare is foaling it is better to minimise interference and to only respond when there is a problem. There are three stages of labour. The first stage is when the foal is getting into the correct position to be born, this may take several hours. During this time the mare may become restless, sweat, look at her flanks and get up and down. The second stage of labour begins with the passing and breaking of the water bag, it ends with the complete birth of the foal. Ideally mares should foal lying down. The second stage of labour involves the forceful uterine and abdominal contractions required to give birth to the foal, typically the mare will be lying on her side. Nearly all foals are born in a diving type posture, so the first thing you will see is a pair of feet. The soles of the feet should face downwards, if they do not the foal is either upside down coming in a breach presentation, either way you are going to need veterinary assistance. Typical in a normal presentation one foot will be further ahead of the other, it may be a good idea to try and pull them both out to the same position, as this will stop the elbow of the leg that is further back from catching at the pelvis. Next the muzzle will follow. If the mare seems to be making little progress it is a good idea to apply a bit of traction to the legs. Grip the fetlocks and hold firmly between the abdominal contractions, this will stop the foal going back in as the contractions relax.

If more forceful traction is required pull back and down towards the mares fetlocks. Once the foal’s head has been passed it may be necessary to clean any membranes from the nostrils. The average length of the second stage is 17 minutes, if after this length of time when forceful expulsive efforts have been made and the foal has not been produced veterinary assistance should be sought. The third stage of labour involves the passing of the placenta. Once the mare stands after foaling the placenta should be knotted at the level of the hocks to prevent the mare from standing on it. The placenta is usually passed within one hour, if it is not passed within three hours veterinary assistance will be required. The placenta should be kept for your vet to examine.

Once the foal has been born, if all is well, the mare will usually lie quietly on her side or siting on her chest for a few minutes. During this time the foal’s hind legs will probably still be in the birth canal and the foal’s umbilicus will still be attached to the placenta, as much blood from the placenta, as possible will be retained by the foal. The umbilicus will break at a natural weak point when the mare stands; it should not be cut and only clamped if there is excessive bleeding from the umbilical stump. Once the cord has broken it should be treated with a 0.5% chlorhexidine solution or liberally sprayed with antibiotic spray. After a few minutes the foal can be pulled, on it’s back by the front legs, under the mare’s nose for her to lick. It is essential that the mare-foal bond be firmly established in the first few hours after foaling, thus minimal interference is recommended.

Foals generally stand within the first 30 to 60 minutes and very quickly hunt for the milk bar. The first suckle is usually observed within 2 hours. With minimal interference the foal may need gentle steering in the direction of the udder. Some mares may need to be restrained to allow the foal to suckle for the first time. If the foal does not suckle within 4 hours veterinary advice should be sought, the best time for absorption of colostrum is in the first 12 hours. The best time for a veterinary surgeon to check that the mare and foal are healthy is between 12 and 18 hours after foaling.