from the Vet Corner Archives
Part of Horse Previews Magazine website. Posted on 05/07/99; 2:00:00PM.
Veterinary Corner 5/99: Foaling Season Is Here!
by Frosty Franklin, DVM
Edgecliff Equine Hospital
S. 1322 Park Road, Spokane, WA 99212 * 509/924-6069
Foaling season is upon us and many mare owners are experiencing sleepless nights as they await the arrival of their new foals. Wouldn't it be nice if our mares could talk to us and tell us, "Tonight is the night. No need to set the alarm every hour. I will be delivering a foal at approximately 11:00pm." Unfortunately, horses have not developed the ability to verbally communicate with us so we must rely on other signs to determine when we can expect the birth of a new foal.The onset of birth in the mare is preceded by many physical changes. Her udder will fill with colostrum (mare's first milk) and distention of the teats will occur. This udder filling is often called "bagging up." You will also notice relaxation of the sacrosciatic ligaments (near the tail head) and relaxation of the vulva. These physical changes signify that birth is near, but it is extremely difficult to say just how soon foaling will take place. It is during this time that the sleepless nights begin. If you are lucky enough to find your mare about to give birth, do not be too nervous. Stay quiet and calm and try not to disturb the mare too much. In order to help ease any anxiety you may feel about the foaling process, I have outlined the 3 stages of labor.
STAGE 1 signs include increased restlessness with the mare pacing the stall, lying down and getting up frequently, switching her tail, stretching as if to urinate, and looking at her flanks. The mare may pass small amounts of feces frequently. Yawning may also be seen during this stage. You may notice patchy sweating behind her elbows, in the flanks, and along the neck as early as 4 hours before birth. During this stage the fetus is repositioning itself to a dorsosacral position with its front legs and head extended. It is very important not to disturb the mare during this stage because if she becomes upset or excited this stage can be delayed for several hours or even days. One word of warning during this stage must be made. If the red, velvet-like chorioallantoic membrane appears intact at the lips of the vulva during this stage or the next, it should be broken immediately and your veterinarian should be called. This situation indicates premature placental separation and if it is allowed to continue, the foal will not get enough oxygen to survive.
STAGE 2 labor begins with the rupture of the chorioallantoic membrane and the passage of allantoic fluid from the vulva (breaking water). Next, the transparent bluish white amnion appears in the vulva. At this point the mare will usually lie down. It is during this stage that the most forceful contractions occur as the fetus is passed through the birth canal. During a normal delivery, the foal usually presents with one foreleg preceding the other by about 10-15cm. The most forceful contractions occur when the foal's head and then shoulders pass through the pelvis. This stage can be completed in less than 10 minutes, but averages about 20 minutes. When the foal's hips pass through the vagina, the mare stops straining and stage 2 is completed. At this point, the mare will usually rest for 10-15 minutes.
STAGE 3 involves passage of the placental membranes. Visible straining stops with delivery of the foal, but contractions continue. The mare may show signs of colic during the passage of the placental membranes. These signs can include uneasiness, pawing, lying down, and rolling. If the mare becomes very distressed, walking her until the placenta is passed may avoid any complications. The placenta is normally passed within 3 hours after delivery of the foal and signals the end of stage 3.
If you are concerned at all about the foaling process and what steps you need to take to ensure a safe delivery and healthy foal, discuss them with your veterinarian prior to your mare's due date. It is important to have an emergency plan in place just in case something goes wrong.
Until Next Time,