Mares should be ultrasounded between 13 and 15 days after ovulation to detect twins. At this time twin embryos can me separated, and one can be pinched with good success. Earlier than day 13 one may not find the embryo. At day 16 the embryo "fixes" and cannot be moved. If the twins fix side by side they cannot be pinched, though other methods of reduction are still available.
By ultrasound the foal's health can be assessed. The fetal heart beat can be seen on ultrasound by day 23 and easily on day 28. Some insurance companies require the pregnancy to be ultrasounded and the heart beat observed.
Once pronounced in foal, mares should ideally be rechecked weekly until day 35, since this is the period most embryonic death occurs. Day 60 and day 120 are also good times to check the mares.
For the first two trimesters of gestation the fetus puts minimal demands on the mother. The last trimester is when the fetus grows most rapidly, and a mare's nutritional needs begin to increase. During lactation is when the mare's requirements are at their highest, requiring additional protein and calcium. Commercial feed companies put out formulated diets that meet the nutrient requirements of the mare. However, as much as possible, mares should be observed and fed as individuals.
The new born foal is protected by antibodies in his mothers first milk (colostrum). Transfer of antibodies from mother to foal takes place in the first 24 hours after birth. Neonatal septicemia is one of the most common causes of death in foals, and is almost always due to failure of the foal to receive adequate colostrum. Vaccinating the pregnant mare in late gestation boosts her immunity which is then passed to the foal. It is common to vaccinate mares against tetanus, rhino, flu, and botulism.
Mare may be restless and colicky for about two hours. Uterus is beginning to contract and move foal into birth canal. Sign's vary from mare to mare. Tail may point straight out. May urinate frequently. If possible, wrap the mare's tail.
Water breaks. Large amount of fluid seen pouring from vulva. Mare may stand or lie down to strain. The amnion, a white membrane, appears at the vulval lips, covering one front leg with the other a few inches behind. The muzzle follows shortly after. The mare strains forcibly. The fetus is expelled in about 5 minutes, wrapped in the amnion. If covering the nose the amnion should be broken so the foal can breathe. The mother may rest for a few minutes. She then stands to investigate the foal which breaks the umbilical cord. There is usually no need to cut or tie the umbilical cord.
The placenta should be passed within 3 hours. If it has not been passed in 6 hours it is a medical emergency and a veterinarian should be called to place the mare on medication until the placenta is released. Do not pull the placenta from the mare. The placenta should be saved for the veterinarian to examine. If the placenta is not complete a portion may still be retained inside the uterus.
If a red, velvety bag is presented at the vulva it must be cut with scissors and the foal delivered as soon as possible. This condition is known as red bagging or premature placental separation. The red velvety bag is the chorioallantois which should rupture inside the mare at the cervix when the water breaks. Unruptured the foal is unable to break it open by his movements and he will suffocate. If a mare goes down to strain without the water breaking, that indicates she may be red-bagging.
If both front legs and the head are not presented then the foal is positioned incorrectly and veterinary assistance should be sought. Abnormal positions include one or both front legs back, the head back, or a foal born backwards, with one or both rear legs retained. If following the waters breaking, the mare has strained for 20 -30 minutes without appearance of the foal the veterinarian should be called.
Using milk electrolyte veterinarians may choose to induce foaling in high risk mares. Milk electrolytes indicate fetal readiness for birth.
The navel should be dipped in a 3.5 % iodine solution. 7.0% or tincture of iodine is too strong. The following are the normal milestones for a normal foal.
| Parameter | Time | |
|---|---|---|
| Time to suck a finger | 2-20 minutes | |
| Sternal Recumbency | 1-2 minutes | |
| Time to stand | 1-2 hours. Longer than 2 hours is abnormal | |
| Time to nurse | 2 hours. Longer than 3-4 hours is abnormal |
If possible, check the specific gravity of the mares colostrum. It should be 1.06 or greater. (Colostrometers are available from Lane Manufacturing. Loveland C0). This indicates sufficient antibodies in the milk. A veterinary examination should be performed on the foal to detect any congenital abnormalities