Ask The Vet!
Pregnancy, Foaling & Newborn Care
PREGNANCY , FOALING, AND NEWBORN CARE
The most predictable thing about equine pregnancy and foaling is it's unpredictability! Usually, mares will carry a foal anywhere from 320 to 345 days, but some mares have foaled healthy babies from 305 to 400 days gestation. I do consider a foal premature if it is born before 320 days gestation. During this long wait the mare owner has a lot of things to attend to and be aware of to insure a trouble free experience for both dam and foal.
I. DISEASE PREVENTION IN THE PREGNANT MARE.
Be sure the mare is on an appropriate parasite control program. The mare should be regularly dewormed with an Ivermectin product such as Eqvalan or Zimectrin every 6 to 8 weeks throughout gestation. I like to be sure to deworm them 30 days prior to foaling, at foaling, and 30 days after foaling. This insures that the foal's first meal and it's first environment are as parasite free as possible.
Immunizations during pregnancy will help prevent abortion and provide antibodies in the colostrum or first milk. The most common cause of viral abortion can be greatly reduced by vaccination against the Herpes virus of Rhinopneumonitis. The mare should be vaccinated with a killed product at the 5th, 7th, and 9th month of gestation. I prefer to use Pneumabort-K by Fort Dodge. This disease can also be greatly reduced by keeping pregnant mares isolated from young horses (<3 years old) and traveling horses. Tetanus toxoid should also be boostered 30 days prior to foaling.
The foaling environment should be safe, clean, and sheltered from wind and rain. The mare's privacy must be considered as well when choosing a site for foaling. Most mares foal at night and if given the opportunity would rather not have anyone watching. If the mare is to foal in a stall it should be at least 14' x 14' and the bedding I prefer is straw. Shavings and rice hulls tend to be too dusty and irritating to newborn's airways and slow to blink eyes. If pasture foaling is done you can bet she will plop the foal under the fence or in a puddle or creek bed. The pastured mare is usually happier and more relaxed about her situation, but she does require a bit more supervision on the owner's part.
Nutrition of the pregnant mare is not altered until she is closer to her 5th through 7th month. Nutritional guidelines are just that and you must take into consideration each individual mare's condition and how much feed it takes to keep her looking good. The amount of hay fed can vary from 1 to 2 pounds of good quality alfalfa per 100 pounds of body weight twice daily. The grain amount can be about half that amount. Remember , these are only guidelines. Feeding bran mash is a good idea as the mare advances in gestation to prevent constipation. Any feed increase or changes must be done gradually over a 2-3 week period to prevent upsets. Most mares can do light to moderate workouts up until the last few weeks of foaling so if you have a working mare the feed requirements must keep her fit not fat. A fat mare will tend to have more problems foaling than a thin mare, but a skinny mare may not be able to give her foal all it needs for growth and strength. I prefer to find a happy medium. There are a lot of products on the market for nutritional supplements and I tend to stay away from them and use good quality hay and Omelene 200 to 300 to keep nutrient needs met. Once milk production has started the demand for calories will jump. The maximum milk production occurs about 3 months after foaling so expect to keep up the grain to about 5 to 8 pounds twice daily at this time and back down to zero pounds by weaning time ( 4 to 8 months).
II. SIGNS OF IMPENDING LABOR AND DELIVERY
The most common sign to look for indicating impending labor is mammary or udder development. This can begin about 1 month prior to foaling with the most dramatic increase in size and fullness occurring about 1-2 weeks before foaling. The nipples will distend with colostrum about 24-48 hours before birth. A waxy secretion can be found at the opening at this time. Some mares will leak milk for days or weeks before foaling, but the colostrum has a different characteristic and will be sticky yellow instead of milk's bluish white color. If the mare leaks a steady stream of milk for even a few days prior to birth the quality of her colostrum may be in jeopardy. If this occurs it is a very good idea to either have a supply of stored colostrum on hand at birth or milk the mare a little each day and freeze it for later. The only source for infection fighting antibodies for the foal is through mother's first milk. There is a very narrow window of time when these proteins can be absorbed through the foal's digestive tract ( within 6 hours of birth ) so it is imperative that the quality of this milk be preserved. A mare that leaks milk for weeks prior to foaling is likely to have very poor quality colostrum at foaling. The calcium level in the milk just before foaling rises to a certain level and there are commercially available kits that use milk's calcium levels to predict foaling to within 24-48 hours. This test may be useful to plan an induced and therefore controlled foaling or just to help you get some sleep knowing your mare won't foal for a certain number of days or hours until the test tells you otherwise.
The vulva and sacro-sciatic ligaments take on different characteristics as foaling time approaches. As the last few days of pregnancy go by the vulva elongates and gets more swollen and loose. The mare does not experience a vaginal discharge at this time as in other species. The ligaments at the base of the tail and the pelvis will loosen as well and in some mares you can see a depression in the muscles on either side of the tail. In general the muscle tone in the rear quarters of the mare tends to diminish as foaling approaches.
III. THE THREE STAGES OF LABOR
STAGE ONE:
This is the time when the mare shows colic symptoms while the cervix is dilating. For some mares this is mild discomfort and for others it is more painful and you may notice sweating, pawing, laying down and getting up, frequent small stools, yawning, etc. Occasionally this is interrupted if the mare becomes startled or nervous and the foaling may be postponed for several hours or even days.
The foal plays an active roll in positioning itself for birth. Toward the end of stage one the mare often rolls as if to help the foal get into the proper position. This stage is ended with the rupture of the "water bag". There is no real need to worry about how long stage one takes as long as the mare doesn't hurt herself or seem unusually painful.
STAGE TWO:
This stage starts as the urine-like allantoic fluid exits the vulva. As the foal is passing into the birth canal the mare starts the obvious abdominal contractions. This causes the bluish-white membrane that surrounds the foal to appear at the vulva. The mare will almost always lay on her side by this time. If a velvety red membrane appears here instead take a blunt instrument or your fingertips and open it up and get the foal out as soon as possible. You will not have time to wait for your vet to intervene for you. This situation indicates premature placental separation and the foal's oxygen and blood supply is quickly disappearing.
The mare may give 3 or 4 good pushes and the foal is readily forced out. Some mares may stand up and lay back down and resume pushing with the foal partially exposed. If the mare is in stage two and pushing for more than 10 minutes then she must be carefully and meticulously checked for foal positioning problems. The normal presentation for the foal is to be front feet first with one foot about 3-6 inches behind and on top of the other leg and the nose following soon behind. If any other presentation exists the foal and mare may be in grave danger. This is also a good time to be sure a forefoot isn't pushing upward and tearing into the rectum as the foal advances. If strenuous pushing fails to advance the foal once the feet and nose are through then intervention is needed. Only pull while the mare is pushing and only after you are continuing to make progress. A rear hoof may be up against the pelvic canal and be preventing advancement of the foal. Most mares are capable of foaling unassisted and it is unusual that we have to intervene.
Stage two should last from 10 to 30 minutes and it is advisable to leave the stall or foaling area when the foal's hips have cleared the vulva. I like to be sure at this time that the foal's nostrils are free from membranes and fluid and then I give the mare as much privacy as possible for the last moments of foaling. You must hold your cameras and outward excitement at this time because you do not want the mare to stand up too soon and sever the umbilical cord prematurely. As much as 1 liter of blood is given to the foal as it lays there still connected to it's mother. Some mares will stay down for 30 or 40 minutes. Once the mare rises the cord usually severs on its own about 2-3 inches from the foal's abdomen. If the placenta is expelled before the mare stands then you will have to sever the cord. Be sure to hold the cord close to the foal's body while you tear or crush it so you do not pull against the foal's belly and create a hernia. Immediately treat the umbilical stump with 2-3% iodine. Don't wait for the foal to stand up.
STAGE THREE:
This is the stage where the placenta is expelled. It may occur while the mare is still recumbent after an exhausting foaling or it may occur once the mare is up and standing. Some mares will go through a mild colic at this time as the uterus contracts again. It may be helpful to walk the mare a bit to help her with her discomfort. The placenta should be delivered within 3 hours of delivery of the foal. Any longer than this can lead to a uterine infection or subsequent laminitis. This is the reason you want to collect the entire placenta and save it for later inspection to be sure all of it is there. A chunk of tissue left behind can be devastating. It is also a good idea to examine the placenta for color and texture to give us clues to the health of the foal. It is best examined by a vet within 8 hours of foaling to note any abnormalities.
IV. AFTERCARE OF THE MARE AND FOAL.
The foal should stand and nurse within the first 3 hours of birth. Before it stands is a good time to treat the umbilical stump with a mild (2-3%) iodine solution. I like to repeat this treatment daily until the stump is completely dry and hard. In some foals this can take a couple weeks and in others it can take a few days. Remember, a navel infection can kill a foal so don't skimp on this task! If the foal doesn't nurse within 3 hours then it should be bottle-fed colostrum or even fed by stomach tube. Be sure a good source of quality colostrum is available to you within the first 6-8 hours of birth. The foal's intestines can not absorb it after this critical window of time. Some colostrum from another mare on the farm is best, but if that isn't available then an outside mare's colostrum will do. If you have frozen colostrum available do not thaw it by microwaving! The foal should receive about 2 pints.
A warmed Fleet enema can be given at this time to aid in the passage of the foal's first bowel movement. This material will be sticky and tarry looking and can sometimes lead to colic if it is retained. The foal should pass this within the first 6-8 hours.
It is a good idea to give the mare 1-2 pounds of bran a day for the first several days after foaling. This is really helpful if she has a lot of swelling and even some small lacerations in the vulva area.
The only silly question is the one you don't ask. If something doesn't look right it probably isn't and foaling is a quick procedure. There usually isn't time to wait and see if things get better. If in doubt call your vet.