How is the foaling date predicted?

The gestation period is 338 days, or approximately 11 months, on average. 
However, deviations are possible, between 310 and 365 days and sometimes 300 days for first foal. 
Males may be carried 3 to 4 days longer than females; gestation is more likely to go over term at the beginning of the year, whereas foaling at term is more likely in the spring. 
There are no 100% reliable methods for accurately determining the due date. 
However, different systems are available, such as video, belts and alarms which may be reassuring to a certain degree in terms of monitoring. 
Primiparas (1st foal) must be monitored from day 300. 

Foaling preparation:
Prepare a large stable with deep straw bedding, to help the mare feel as comfortable as possible. The ideal situation is to stable her each night from 10 months of gestation so that the maximum amount of specific antibodies to potential infections in the foaling environment is present in the colostrum (first milk) so as to give the foal proper immune system protection. 
Tail bandaging is recommended and the veterinary surgeon will carry out an episiotomy of the perineum (cut along the vulva scar) if the mare has had stitches in the past. 
If the vulva is not cut, this will dangerous for the foal, with a high risk of mortality since the foal may suffocate if the water bag has not fully ruptured if the birth canal is too narrow. 

Striking signs to foaling:
The most striking signs that a mare is ready to foal are: 

  • “dropped” hindquarters, 
  • larger teats 
  • the production of “wax” on the tips of the teats. Waxing up does not necessary mean that birth is imminent since mares may foal without increased teat size or without waxing up to everyone’s great surprise. 
  • The mare’s vulva will relax and the mare will try to find a quite place on her own in the paddock. 
  • During the hours leading up to foaling, the mare will show signs of sweating around the elbow behind the forelegs (girth) and also around the chest. 
  • Flattened bedding is another sign that foaling is imminent since mares become restless and move around the box. 
  • Some mares may appear anxious. 

Foaling period:
Delivery (expulsion of the bag) should take place within six hours of foaling. 
It is vital that you contact your veterinary surgeon if delivery has not progressed normally, and also for any possible problems such twisted uterus, haemorrhage, and the beginning of labour. 
As a general rule, in 70 to 80% of cases, foaling takes place during the night. 
The whole process should take 15 minutes on average, but may vary from 5 to 45 min. 
Labour should take place in three stages: presentation, expulsion and delivery. 

Do not hesitate to contact your veterinary surgeon if foaling does not proceed as expected.