Stages of Pregnancy in a Mare and Foal Birth
Normal Gestation of a Mare
Spring is here and the long wait is coming to an end. Your mare's due date is approaching. Normal gestation for a mare is 335-360 days, so you have about ten days leeway on your foaling date even if you have kept careful records noting the days she was bred. So don’t get too nervous if even day 360 rolls around without a newborn foal appearing. Some mares do go 12 months without a problem. But, if you are approaching day 360 it is a good idea to have your vet check on the mare to be sure all is well.
The Mare's Last Trimester
It is the last third of your mare’s pregnancy when you begin to observe changes. During the last trimester you should move your mare to the area where you want her to deliver. This is so she is exposed to particular bacteria and viral antigens and her body can produce the antibodies to them. She can then pass them onto her foal during birth. Also, she will be comfortable in her new surroundings before the due date.
In the late stages of pregnancy, you will notice the mare’s belly has enlarged and she will be less active than normal. In the last two to three weeks the abdomen muscles become more relaxed and the foal will “drop.” This is usually more obvious in older broodmares.
In another week’s time, the muscles on either side of the tail head become very soft somewhat like Jell-O. In the last two week period, the mare’s udder will begin to enlarge until during the last week the teats fill out. When you can see a clear secretion you are approaching the last week or days of pregnancy. By the last two days, the secretion becomes thick and cloudy, sometimes leaving a milky droplet on the end of her teats. This is what is called “waxing.”
Do not be alarmed if in those last days your mare experiences edema along the center of her underbelly—called ventral edema. Turning her out in a larger area to move around more a few hours a day or hand walking her will help with this. It has nothing to do with her milk as some old wives tales indicate.
Four Stages of the Foal's Birth
Birth of the foal happens in four stages.
In phase one the mare will be restless and even seem to have mild colic. She will lay down, get up, nibble hay, swish her tail and repeat. This indicates the last couple of hours before foaling.
In the second phase her water will break. The mare is usually standing up when this happens. The front feet of the foal will appear in this phase, which takes about fifteen minutes. If 20-30 minutes go by and the feet do not appear call the vet because she may be having trouble. Most mares deliver easily and quickly. If you need the vet walk your mare until she or he arrives.
In the third phase of normal birth the mare usually will lie down and labor begins. In a normal presentation the amnionic tissue with one foot appears (in phase two) with the sole of the foot downward, the other foot appears next and then the nose of the foal. Anything different from that and you should call your vet.
The foal delivers quickly after that initial presentation. The mare will remain lying down for a few minutes. This gives her time to rest and the blood to flow from her to the foal before breaking the umbilical cord. The cord will break naturally when she stands up – do not cut the cord as this may cause hemorrhaging.
The passing of the afterbirth or placenta is the fourth and final stage. This can happen a few minutes to one hour after the foal is born. Again the mare will experience contractions and behave as though she has colic. This may continue even for a few hours after the placenta is expelled. Examine the afterbirth to be sure it is intact. Any part left inside the mare can cause infection and serious consequences. If the placenta is not expelled within two hours call your vet. A retained placenta can also cause complications.
It is very tempting to jump in and “help” the foal to its feet and guide it to the teats. This is not usually necessary. Just be sure the foal is breathing, remove any membrane that may be covering its nose, then let nature do her job. Have your vet come give the foal its first check-up to be sure the heart and lungs are working normally. The mare’s milk contains important antibodies that will protect the foal from disease until its own immune system develops. The colostrum, or first milk, contain these healthy benefits only during the first 24 hours after birth so it is important that the foal nurse during that time. Some new mothers are reluctant to let their foals nurse and may have to be restrained at first. Once the foal has nurse and relieved some of the painful pressure the mare feels on her udder she is usually fine and will let her foal nurse without a problem.
Now you can call your friends to come see your beautiful new foal, and get the cameras rolling. But, don’t overtire the mother and baby; they need their rest.
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.
© 2009 Donna Campbell Smith