By Jen Roytz
From breeding decisions to caring for a mare before and throughout her pregnancy, the birth of a foal represents a year or more of planning, spending and waiting. Ideally, the scenario proceeds uneventfully and the result is a healthy foal, but in the less than 5% of the time when things go wrong, they can quickly turn into a life or death scenario for both the mare and foal without immediate, educated assessment and intervention.
A dystocia, which is the over-arching term for issues that interfere with the typical birthing process, generally refers to the foal being malpositioned in the birth canal, and thus preventing a normal delivery. The delivery of a foal is naturally a rapid, forceful event. When an animal with the muscling and abdominal strength of a typical broodmare continues to attempt to push a foal out when it is, for one reason or another, lodged, major complications can quickly arise, threatening the health of both the mare and foal.
In a typical delivery, a foal will exit the birthing canal feet first, followed by its nose, head, shoulders, barrel, hips and finally hind legs. When that scenario does not happen in close succession, a variety of strategies can be implemented to assist the mare and ultimately save the lives of both the mare and foal. These can include manual manipulation by hand, the use of ropes or chains to create traction, rapid assisted delivery and c-section.
There are a number of ways the process can go awry, all of which require immediate intervention, including:
Red Bag Deliveries occur when there is a premature separation of the placenta before or during foaling. The equine placenta has two major parts–the red bag (chorioallantois), which is responsible for providing nutrients to the fetus during gestation, and the white bag (amnion), which surrounds the fetus and offers protection. In a typical foaling, the red bag should break just prior to the foal entering the birth canal, the white bag is what is seen first as the foal is being delivered and the red bag is passed within three hours of the foal being delivered. If the red bag appears first, it is imperative to carefully cut the bag open with surgical scissors, feel for the proper presentation of the front legs and nose of the foal, then carefully cut the white bag to expose the foal.
Front leg(s) back-when one or both legs are flexed at the knee or contracted, it causes the foal to become trapped in the birth canal and unable to be delivered. Often this can be easily corrected by repelling the foal (pushing the foal back in) and manually manipulating to gain access to the flexed limb and extending it to resume normal delivery.
Retention of the head occurs when either one of both of the forelimbs protrude through the vagina, but the head does not follow. This occurs when the foal is not positioned properly in the birth canal or is a wry neck fetus, resulting in the head and neck being bent backwards. To prevent the mare from continuing to push it is best to get the mare up and walking, as often this can help to correct the position of the foal. A sterile rope or cord can aid in the process, passing it over the foal's lower jaw to allow the attendant or veterinarian to pull the head and neck into the proper position, however if that does not result in a successful delivery, a caesarian section or fetotomy (dismemberment of the foal surgically) may be necessary.
Upside Down presentations are one of the more typical types of dystocias and occur when the front feet facing up and the head is turned the wrong direction, which means the foal has failed to rotate to the normal dorso-pubic position. In some cases, an experienced foaling attendant or veterinarian can use the presenting limbs to manually rotate the foal into the proper position, using traction to adjust the foal into proper position as delivery begins. In other cases, ropes or chains may be attached to the pasterns of the forelimbs to reposition the foal and begin delivery until the mare's contractions can complete the process unaided.
Hip Lock presentations occur when the foal's hind quarters are unable to pass through the mare's pelvic cavity for normal delivery. Typically, the issue is detected once the foal is partially delivered up to the thorax. Often the attendant will pull the foal down in the arcing presentation between her hind limbs, forcing the foal's hind quarters into the area with the greatest diameter of the mare's pelvis, which should then allow the foal to be delivered vaginally.
Breech–In this scenario the hind limbs or quarter of the foal presents first and the mare's continued contractions cause the placenta to separate, which can result in asphyxiation of the foal. If the foal is able to be delivered alive, the umbilical cord may have unknowingly been compromised, resulting in a variety of possible complications, including broken ribs or delayed hypoxia due to brain swelling that can lead to a dummy foal, seizures, etc. Early recognition is important and often a c-section or assisted vaginal delivery is required.
When manual manipulation by hand fails, the next step is often assisted vaginal delivery (also called “controlled delivery”). In this scenario, the mare is put under anesthesia and her hind quarters are lifted so the foal is able to slip back into the birth canal, where it either naturally falls into a more desirable position or can be manipulated by hand into such a position that it can be delivered without surgical intervention.
One of the most important factors in any type of birthing mishap is having an educated foaling attendant on hand who can make informed, timely decisions about how best to assist the mare, when to call a veterinarian and when to send the mare to an equine hospital for more invasive care.
In the case of a severe dystocia, the question of whether the focus should be to save the mare or the foal will often arise. While the ultimate goal is a successful outcome for both, the question should be addressed prior to the severity of the dystocia reaching a climax.
It is also wise to keep track of the amount of time that has passed since the mare was found to be in distress. If a veterinarian is called in for assistance, this can help him or her gauge how long they have to work on the dystocia before making the decision to send the mare to the clinic and can help them prioritize their approach to the situation at hand.