Foaling Mare

The first rule of foaling is DON’T PANIC! The majority of foalings happen normally and don’t require any intervention. In order to know when to intervene or when to call for help, it is important to know the normal foaling process, and know the warning signs to look for. The average gestation length of the mare is 340 days with a range extending from 315-365 days. Mares usually undergo physical changes in the prepartum period to indicate that the foaling date is approaching. These changes include enlargement of the udder, filling, distension and “waxing” of the teats, relaxation of the tailhead, flank area, and vulva. Because mares typically foal at night, having a monitoring system or scheduling frequent night checks can be an important part of making sure the foaling is attended. The parturition (foaling) process is divided into three stages.

Stage 1

Stage 1 is the preparatory phase and may last from 20 minutes to several hours. In this stage, the foal repositions inside the mare, and the cervix dilates. The mare may be restless and show signs similar to colic (getting up and down, flank watching, urinating frequently, and sweating). The mare’s uterine contractions push the foal’s head and forelimbs into the pelvic canal. The mare should not be disturbed during this stage, as this is an important time for the foal to reposition. If the mare feels threatened at this stage, foaling may be delayed. If stage 1 is taking longer than 3-4 hours, call your vet.

Stage 2

Stage 2 is the active stage. The start of Stage 2 is when the waters break. It is during this stage that active contractions begin. The chorioallantoic membrane ruptures as the foal comes into the pelvic canal, and several litres of allantoic fluid will be released (waters breaking). Within five minutes of the waters breaking, the amnion (white and shiny membrane, Figure 1) should be present at the vulva. The mare will be straining to deliver the foal at this stage. If it has been more than five minutes, and no amnion is seen, call your vet. If the membranes present at the vulva are red and velvety, the placenta may be separating prematurely. This is also called a red bag presentation (Figure 2). This is an emergency; call your vet. Premature placental separation may lead to a compromised supply of oxygen to the foal. The red membranes need to be broken, and the foal delivered as quickly as possible.

The mare may stand and lay down repeatedly during this stage. A normal presentation is two front feet (one slightly in front of the other initially, with soles pointing down), then the nose. If the foal is not in a normal position, a veterinarian should be contacted right away. Delay in delivery at this stage can greatly affect the chances of the foal’s survival. The amniotic sac usually ruptures during birth; if not, it should be gently opened and removed from around the foal’s nose and muzzle immediately after the delivery. The mare’s contractions can be extremely strong, and the foal is usually delivered within 30 minutes of the waters breaking. If at any time, the delivery does not appear to be proceeding as normal, or if more than ten minutes pass with no progression, call your vet.

Stage 3

Stage three of parturition is expulsion of the foetal membranes and uterine involution. If the placenta is dragging on the ground, it can be tied in a knot at the level of the hocks to avoid it tearing or tracking mud/bacteria into the uterus. The placenta is usually expelled within 30 minutes to 3 hours after foaling. Examination of the placenta is an important part of a veterinary evaluation of a mare and her newborn foal, so, when possible, save the placenta in a cool, dry place in a clean bucket or trash bag. Retained membranes occur in 2-10% of foalings, and retention is more common after dystocia (difficult foaling). If the mare has retained membranes, she is at great risk of infection and laminitis. For this reason, the mare needs to be seen by a vet if she has not passed the membranes within 3 hours of foaling.

As always, do not hesitate to contact Veterinary Associates with any questions. The best way to avoid problems is to be prepared with a plan!