Pregnancy in Horses

Gestation or the term of pregnancy in a mare is around 340 days. However, the mare’s breeding history and age can also play a major role in determining how long the gestation period will last before the mare is ready to foal. The weather also plays an important role in determining when the mare is going to foal. If the weather is warm then the gestation is shorter and if the weather is cold then the gestation is longer.
During the gestation period the mare should still be ridden and continue her normal routine as it will help her when it’s finally her time to foal. You should be careful in the 7th month and avoid any strenuous activity and hard jumps as it will create a lot of pressure.

The most exciting stage in mare’s pregnancy is when you are trying to determine whether the mare is pregnant or not as you won’t know for sure in the first two months. The veterinarian will perform the urine and blood test only between 60 to 100 days. At 100 days the foal is around 7 inches long and its main features begin to develop. During the midterm which is between 100 to 250 days the veterinarian will suggest another test as many mares have a miscarriage in the first stage. The foal weighs around 2 pounds at 150 days and by 180 days it weighs 10 pounds. During this stage the foal is the size of a tiny lamb and the mare shows noticeable abdominal weight gain. The third stage of gestation is after 250 days where the foal continues to gain weight rapidly and his lungs develop. The mare also shows noticeable changes at this time. The udder produces a sticky yellow discharge that turns into milk later.  Her abdomen grows very heavy during this time.  By this time you should be ready for foaling although it won’t happen for at least 55 days. Observing the mare on a daily basis is the only way you can keep a check on when the mare is going to foal.

The mare has the ability of postponing the birth if she it is not comfortable with the surroundings. Foaling usually begins at night and finished by the early morning. Never rush the mare - let it foal naturally and do not interfere. It begins nursing within 30 minute to 2 hours after the delivery. This milk contains essential antibodies and Colostrum that is essential for the new foal.