Timing Foaling

With the amount of time that it takes for a horse to gestate we definitely want to make sure that the foal is as healthy as possible, the mare as well. The normal gestation period of a horse is 340 days but can range +/- 5 days either direction.  With that being said knowing the signs of parturition (birthing process) of your mare will greatly help you to narrow down that window.

The best practice is to keep records of your mares pervious foaling if she has had any.  Many mares repeat these behaviors year after year.  Udder development begins 2 to 6 weeks before foaling and milk letdown into the teats occurs 4-6 days before foaling.  The "oozing" of the colostrum or first milk, will cover the ends of the teats causing a "waxing" effect which begins 1-2 days before foaling.  If you have a steady stream of the colostrum you should attempt to collect this for possible use in the newborn foal.  In addition to the mammary development you can tell a muscular relaxation in the pelvic region 7-14 days before and the mare's vulva will relax and swell during the final days of gestation.

Some commercial kits have been created to estimate foaling times.  These kits are based on the fact that in most mares calcium and magnesium concentrations will steadily rise during the last portion of gestation up until time of foaling.  There is typically a significant rise in the calcium and magnesium levels within the last 12-24 hours with help attendants to be on "foal watch" during this time.  These kits are fairly inexpensive and are available from most Veterinarians.

All in all, whether you are using a kit or not knowing the physical signs of impending parturition will keep both your foal and mare healthier.  Always have a Veterinarian nearby and make them aware of your possible foal time so they can be ready to come assist if necessary.