The period of development from conception to birth (gestation period) is 335-340 days.
During the last 2-6 weeks there will be udder enlargement; the teats will enlarge within the last 4-6 days.
Waxing, whereby the teats become covered in colostrum occurs in most mares; this is usually within the last 1-2 days of foaling.
Other signs may include relaxing of the pelvic musculature (7-14 days) and vulva (2-4 days).
About 80% of mares foal between 6pm and 6am. They prefer quiet conditions and solitude, repetitive checking can make mares delay delivery by hours or even days.
BE AWARE, some mares will break all the rules!
Introduce the mare into her foaling environment at least 2-3 weeks prior to the foaling date.
Foaling box should be clean, dry, quiet and of reasonable size. A deep, clean straw bed is preferable over shavings.
The mare should be allowed to exercise and should not be confined to a box.
If foaling outdoors, the mare should be alone and the field dry with a good covering of grass, free of hazards. It is essential the environment is clean as foals are susceptible to acquiring infections during and just after birth.
Initial uterine contractions and final foaling position
This can last 1-4 hours. Mares will appear nervous, restless and uncomfortable (pawing the ground, stops eating, tail swishing, getting up and down and mild sweating). If possible, bandage the tail at this point.
Expulsion of foal
This lasts less than 30 minutes. If possible, observe the mare closely without interference. The mare will lie flat on her side with heavy abdominal contractions.
The water bag will appear and should break on its own. Both front feet should appear at the vulva with one foot slightly ahead of the other, the foal’s nose should be between and on top of the front legs.
If in the correct position, this stage should progress rapidly with the foal being delivered with 15 minutes of the feet appearing.
Delivery of the placenta
The placenta should pass 3-4 hours after the delivery. Once passed, the placenta should be examined to make sure it is intact.
Keep the entire placenta in a bag to be examined by the vet.
When to call the vet?
If any of the first 2 stages last longer than the time mentioned
If at any time in stages 1 or 2, a red ‘bag’ with velvet like coating appears at the vulva
If the foal has not got to its feet or suckled within 4-6 hours
If the mare does not pass the placenta within 8 hours of foaling