When Foaling Goes Wrong
- Nov 26, 2007
There is something magical about foaling time that involves more than just observing the start of a new life--special though that might be. In addition, it often is the fruition of months, even years, of planning and anticipation on the part of the owner. As we stare in wonder at a wobbly foal, we often see more--a winner on the track, a jumper soaring over fences, a cutting horse making fantastic moves, a reiner leaving "elevens" in its wake … the list goes on.
The anticipation reaches its apex when the mare goes into labor and a tiny hoof makes its appearance, then another, then the nose, the neck, shoulders, and, in a rush, the rest of the body.
Unfortunately, it isn't always that simple and straightforward. Sometimes things go wrong and a potentially wondrous event turns into an utter nightmare.
Quite often when health issues arise with a horse, there is time to evaluate exactly what has gone wrong and carefully plan a course of action to solve the problem. With a birthing problem, technically known as dystocia, one often does not have the luxury of leisurely planning a treatment protocol; time is of the essence.
Juan Samper, DVM, PhD, a reproduction specialist in British Columbia, Canada, and a frequent presenter at American Association of Equine Practitioners (AAEP) and Society for Theriogenology conventions, calls the birthing process a "very explosive" event. If something goes wrong, he says, there is very little time to correct the problem before irreparable harm might be done to both mare and foal.
Once serious labor begins and the mare's water breaks, Samper says, the foal should be on the ground in 30 minutes--45 minutes at the most.
Unfortunately, a rather significant number of foals are lost as a result of dystocia each year. In 2005 the USDA's National Animal Health Monitoring System (NAHMS) conducted a study of equine operations to collect data on equine health and management practices. Involved were operations in 28 states with five or more equids on the premises.
It was found that foal mortality due to dystocia, trauma, or complications at birth accounted for 10.7% of the foal deaths in the study areas.
The problem is once the birthing process gets under way and the horse owner or caretaker realizes something has gone awry, there can often be a delay in the arrival of professional help. Even though a call might be made immediately after detecting a problem birth, it could be a half-hour or more before a veterinarian reaches the farm.
Samper has some suggestions concerning how to discern whether a problem has developed and what to do while awaiting help. Once the mare is down and in labor, he says, first one foot, then the other should make an appearance, followed by the nose and head. To make certain that all is going well, he says, the attendant can reach into the birth canal to determine whether there is proper presentation once the first foot makes its appearance.
"The second leg should be right there, about six inches behind the first foot, and the nose should be about six inches behind the second foot," Samper says.
The reason for the legs emerging slightly staggered, he explains, is because the foal is turned somewhat in order to facilitate the passage of the shoulders through the birth canal. If both feet are together, the shoulders are squared up and, thus, occupy more space. By one limb being slightly forward of the other, one shoulder goes through the birth canal at a time.
If a check of the foal reveals that one of the legs or the head is out of position, it is a clear indication that problems lie ahead, Samper says. Because a mare's contractions are very powerful, it can be difficult to reposition a foal and Samper doesn't suggest that a person lacking in experience give it a try. It is better, he feels, to wait for a veterinarian, if at all possible.
"You have to know exactly what to do and do it quickly," Samper says about an assisted birth that might involve repositioning of the foal. While waiting for professional help, he suggests, an attempt should be made to slow the birth process.
About the only way to slow the process without a veterinarian administering drugs is to get the mare on her feet and walking, Samper says. She still might have contractions, but the abdominal muscles do not work with as much power when the mare is walking as when she is on her side.
In addition there is always the off chance that the foal will slip back into the uterus and reposition itself. This is a long shot, however, and not something on which one should depend. Getting the mare on her feet also might prevent some of the amniotic fluid from being lost. The fluid is a valuable lubricant.
Once the veterinarian arrives, an examination will reveal how serious the problem is. It can range from something that can be relatively easily solved, such as a simple repositioning of a leg, to something much more complex.
Along the way some important considerations come into play. Some of them are based on economics. For example, where does the greater value lie--in the mare or in the foal? If the mare is carrying a
valuable foal as the result of embryo transfer, the answer is rather clear-cut. The welfare of the foal comes first. However, if the mare is a valuable broodmare with some years of production ahead of her, the issue becomes a little less clear, especially if she has been bred to an expensive, high-quality stallion.
The cost of various procedures should also be considered. Perhaps a Cesarean section is the approach deemed most advisable. Should it be conducted in the stall at the farm, where opportunities for infectious bacterial invasions are greater, or should she be transported to an equine hospital, where sterile conditions might prevail, but the cost of surgery goes up?
An individual with appropriate financial means might opt for a more expensive procedure, even if the mare and foal are not of high value, while the backyard breeder on a limited income might have to settle for an approach that is less expensive.
Sometimes other issues influence the decision-making, with geography figuring into the equation. If a Cesarean is required and the mare is in a barn on a ranch with the nearest equine hospital several hours away, the decision might be vastly different than if the same thing happened in a barn in Kentucky where an equine hospital staffed by equine experts is only minutes away.
We will examine some of the approaches that are available and the way in which they are employed. One of the most thorough examinations of the overall dystocia problem in mares occurred during a Society for Theriogenology convention. Experts in the field from around the world gathered to discuss causes, effects, and approaches to solving problems. We'll tap into that gathering as a source of information.
First, however, we'll seek to explain just what happens during a normal birth. This will set the stage for understanding what is happening when something goes awry.
We also will be calling on Samper for more of his observations and suggestions.
First, the basics of parturition, beginning one month before birth. At this stage of development, the foal's primary organs are all where they should be and are
maturing rapidly. The foal is in the amniotic sac within the placenta and is getting nutrition and oxygen via the umbilical cord. The umbilical cord will continue to be the foal's lifeline until the foal has been delivered.
As the countdown continues to one week prior to birth, the foal has grown to the point where it has little room to move within the confines of the uterus. At this point it is upside down. During the final hours prior to delivery, the foal will rotate until it is in the correct position for delivery. As delivery begins the foal will begin to rotate until it is right side up, and its front feet and nose will be at the entrance to the birth canal in a sort of diving position. The foal's back feet will be tucked beneath it in the early stages of labor.
The mare will go through two basic stages of labor. During the first stage, she often is restless and agitated. She might paw at her bedding and lie down and get up with some frequency. It is believed by many reproductive experts that there is a purpose behind the mare's movements and her lying down and rising. It could be that it helps properly position the foal for passage through the birth canal.
The agitation and moving about is the signal for the attendant to be on the alert because the second stage can begin at any time. Just what time interval between first and second stages of labor is most appropriate hasn't been determined. However, most specialists will say if there is a long period of time between the outset of discomfort and the breaking of the water to signal the start of the second stage, it can be an indication that trouble looms ahead.
When all goes well the mare's agitation will increase as contractions increase, and soon the start of serious labor will begin with the breaking of water. The mare normally will lie on her side to facilitate the foal's passage through the birth canal.
We must visualize at this point that the foal is contained within two saclike structures within the uterus. The outer sac is the placenta, which attaches to the inner surface of the mare's uterus and is filled with fluid. The second is called the amniotic sac, which contains the foal, and it also is filled with fluid. In a manner of speaking, the foal is floating around in this fluid-filled sac, which is inside another fluid-filled sac.
When the foal passes into the birth canal, it pushes through the placental membrane and the mare's "water breaks." The amniotic fluid between the placenta and the amniotic sac gushes out, lubricating the vagina. Shortly thereafter, a translucent white "bubble" filled with fluid appears at the vagina. This is the amniotic sac, which surrounds the foal. During the normal birthing process, it, too, will break. Even if it doesn't, there normally is little or no danger to the foal, because it is dependent on the umbilical cord for oxygen until it is free of the uterus and its chest can expand to breathe on its own.
No one has done a better job of explaining just what occurs during birth than O.J. Ginther, VMD, PhD, University of Wisconsin, who presented the State of the Art Lecture at an AAEP meeting several years ago. The subject involved equine pregnancy from fertilization through parturition. What follows are some of the highlights of what he told the group about the birthing process. Direct quotes are taken from the AAEP Proceedings.
Ginther said information concerning exactly what occurs during parturition was obtained during research that involved treating a number of mares with oxytocin (a hormone that stimulates contraction of the uterus) and observing what transpires via X rays, ultrasound, and laparoscopy, along with transrectal, transvaginal, and intravaginal palpation.
"Monitoring parturition events did not appear to affect the ease of birth or the health of the mare and foal," he said. "However, in two examined mares, an unruptured allantochorion (the outer membrane of the placenta) appeared at the labia (the external lips of the vulva)."
He also told the group that the time from injection of oxytocin to stimulate the onset of labor until parturition ranged from 38 to 46 minutes.
"The rupture of the allantochorion with fluid expulsion did not occur until the fetlocks or knees were at the level of the external cervical opening. Thus, any lubricating qualities of the discharged fluid were applied to the vaginal wall as the fetal head was entering the vagina," said Ginther.
He proceeded to explain a series of movements during parturition that led to the eventual rotation of the foal from its position of dorsal recumbency (on its back) to a ventral or "right-side-up" position (such that the spine of the foal faces the spine of the mare).
The final rotation allowing the shoulders to pass through the canal, Ginther said, was completed in about 10 seconds and sometimes occurred as "one continuous motion."
It would be great if all births were normal and incident free. That is not the case. There are many things that can--and do--go wrong. As already mentioned, getting professional help in a hurry is important. To that end, it is wise for the owner to establish communication with his or her veterinarian and alert that professional to the fact that the foal is due on a particular date. If a Caslick's procedure has been performed on the mare (stitching the vulva nearly closed to prevent contamination of the reproductive tract), the attending veterinarian should be apprised of that fact in advance of foaling. A Caslick's should be opened 7-14 days prior to the anticipated due date. This is also a time for the owner to brush up on anatomy. It is highly important, for example, to know the difference by touch between front feet and rear feet.
You can tell whether the correct limbs are aiming out by feeling the first two major joints in the foal's legs: The first two large movable joints in the forelimbs flex in the same direction, and the first two large movable joints in the hind limb flex in opposite directions.
If there is any concern at all during the onset of labor, such as a prolonged period between the first and second stages, a "heads-up" call to the veterinarian or his message service might be in order.
Observation of the mare during the early stages of labor should be from a distance.
Samper tells us that a mare's temperament can have a bearing on treatment protocol when dystocia occurs. Obviously, a mare that is placid and easy to handle is a better candidate for some procedures than one that is nervous and resentful of someone working at her posterior.
There are so many things that can go wrong during what Nature designed as a simple procedure of birth that it is difficult to know where to begin. Perhaps, however, the most common problems stem from the foal being out of the correct position for the birthing process. This might be as simple as one front leg being flexed to as complicated as all four legs being presented at the birth canal at the same time.
Dealing in depth with malposition problems during the aforementioned theriogenology gathering was Robert Hillman, DVM, MS, of New York. Most of his comments were aimed at veterinarians who are called to farms to deal with dystocias, but they also contain valuable information for owners.
Once the problem has been diagnosed, Hillman said, it is important for veterinarian and owner to have a consultation concerning what procedures should be taken to resolve the problem, what the costs might be, and the chances for success. As indicated earlier, there isn't a lot of time for discussion--decisions must be made rapidly and procedures begun with dispatch.
Earlier, Samper strongly suggested that a foaling attendant not attempt to reposition the foal unless he or she is very experienced in the procedure. One of the reasons for that advice involves the power of a mare's contractions. It is almost impossible to fight against them. Instead, the veterinarian has learned to work with the mare--to cease efforts while she is pushing and to work at repositioning when she relaxes.
Here is what Hillman had to say as printed in the Theriogenology proceedings:
"Before attempting correction of any abnormal presentation, position, or posture, it is necessary to carefully repel the fetus out of the pelvis back into the uterus to allow room for mutation (moving it into the correct position). Pumping one to two gallons of diluted J-lube (an obstetrical lubricant) around the fetus prior to starting serves to distend the uterus, providing more room to work as well as supplying the desired lubrication. Judicious repulsive pressure is applied to the fetus between expulsive efforts of the mare. When the mare strains the fetus is held steady, but repelling effort is only applied when the mare is not straining. The fragile nature of the mare's reproductive tract must be kept in mind and any manipulations made as gently as possible, as brute force could result in severe trauma. The use of epidural anesthesia is dictated by the degree of straining and the difficulty anticipated to achieve the required correction. When repositioning the limbs it is important not to ‘fight' the mare. When the mare strains stop manipulations, and when she relaxes make the necessary adjustments. Forcing changes during tenesmus (straining) invariably creates undesirable trauma and can lead to the demise of the mare as well as the fetus."
Samper believes strongly in fully lubricating the uterus while attempting to reposition the foal. In some cases, he says, he has inserted a water hose into the uterus, forcing water to surround the foal. There is virtually no danger that the water pressure will cause damage to the uterus because the excess will be forced out through the vagina, he says.
Earlier Samper explained why one foot is presented in front of the other--to allow easier passage through the birth canal. When this is not the case, according to Hillman, a condition known as elbow lock can occur. An indication of elbow lock presents when one or both feet are at the same level as the muzzle, with one or both elbows lodged against the pelvic brim. The condition is resolved, Hillman says, by carefully repelling the fetus to allow room to extend first one elbow and then the other, to permit delivery.
Another condition involves carpal (knee) flexion. This means the head is ready for presentation, but one or both knees are flexed. When checking on the foal's position vaginally, the nose will be available to touch, but not the front feet.
Once again, the problem is resolved by pushing the fetus back into the uterus, then carefully repositioning the front legs. In the case of a dead fetus, Hillman says, it sometimes is more expedient to perform a partial fetotomy (removal of a dead foal from the uterus in pieces), removing the front legs at the knee joint.
A troublesome form of dystocia is caused by the foot-nape posture. This means that the fetal head is extended into the vagina and the two front legs are crossed over the head with the points of the hooves pointing toward the roof of the vagina. This type of condition must be dealt with swiftly, Hillman says, because strong abdominal straining can result in perforation of both the vagina and the rectum.
Correction of the condition involves repelling the fetus back into the uterus and repositioning the legs so that they are under the foal's chin.
A vertex or poll posture, Hillman says, results when the nose of the fetus catches under the brim of the pelvis. The top of the head and ears will be present at the inlet to the birth canal, but the birthing process will be stopped there until the situation is rectified. Repelling the fetus into the uterus and repositioning the head allows the delivery to proceed.
Described by Hillman as a particularly difficult dystocia is lateral (toward the side) or ventral (toward the belly) deviation of the head and heck. What this means in layman's language is that the neck and head are folded back along the foal's body. The forelimbs will be located within the pelvis without the presence of the head, which is near the hindquarters. In cases of lateral deviation, the head and neck will stretch along the foal's side. In ventral deviation, the head and neck will be folded between the forelimbs, toward the foal's belly.
Attempts at correcting either of these deviations, Hillman says, should be preceded by epidural anesthesia, copious lubrication, and, if possible, standing the mare on a slope so that her rear quarters are elevated. Due to the length of the neck, it might be impossible for the veterinarian to reach in and reposition the head. The veterinarian might be called on to use a head snare, eye hooks, or a towel clamp to grasp an ear or skin. The above three approaches would be used to bring the head within reach of the veterinarian's hand so that the muzzle could be guided into the pelvis.
If the problem isn't resolved within 10 to 15 minutes, Hillman reports, the mare should be considered as a candidate for Cesarean section.
If a referral hospital is located nearby, this might not be a problem, but if none is available within appropriate driving distance, the Cesarean section might have to take place in the stall.
In Samper's experience, mares that have undergone successful Cesarean sections, minus infection, have proven to be good breeders in the wake of the surgery. The same cannot be said for mares that have undergone a fetotomy, he says. Because of the potentially abrasive nature of the procedure, resultant damage to the reproductive tract can result in a problem or infertile breeder.
Other veterinarians say, however, that if a fetotomy is done efficiently and carefully, it's actually less invasive and not as stressful to the mare as a Cesarean. Since equine veterinarians generally aren't as practiced at fetotomies as, say, cattle veterinarians, the procedure might have gotten a bad rap from a few fetotomies in inexperienced hands that didn't go well. But veterinarians well-schooled in the procedure can perform a fetotomy without harming the mare.
Posterior presentations, Hillman tells us, are relatively rare in horses, with only about 1% of equine dystocias resulting from that particular problem.
A more common problem occurs when the fetus presents in a lateral position and becomes lodged at the pelvic brim. The solution in this situation, according to Hillman, is to repel the fetus and rotate it into a dorsal position for delivery.
A condition known technically as transverse presentation, and by some laymen as "dog-sitting," is one of the more difficult to resolve. In this situation the rear legs are drawn up or flexed beneath the foal's underside and lodged against the pelvic brim. The goal of the veterinarian when this problem occurs is to push the rear legs back so that the hips can enter the birth canal, followed by the legs. It is one of those situations where the solution is easier said than done, and some cases where dog-sitting is involved require a Cesarean section.
A potential problem that concerns many horse owners involves an oversized foal. The fact of the matter, Hillman says, is that an oversized foal rarely is the cause of dystocia. When it does occur, he says, Cesarean section is recommended. If the foal is dead, a fetotomy might be in order.
Don't Forget the Mare
It should go without saying that when dystocia is involved, proper aftercare of the mare becomes a high priority. If the dystocia has been quickly resolved, minimal treatment might be all that is required. The more serious dystocias, requiring invasive procedures, might call for a more involved treatment protocol.
Working closely with one's veterinarian before, during, and after the birth of a foal is of top priority. Prepare ahead of time for the steps you will take as an owner if a problem presents during foaling. If all goes well, then nothing is lost, but if you don't prepare, you could lose the mare and foal.
About the Author
Les Sellnow is a free-lance writer based near Riverton, Wyo. He specializes in articles on equine research, and operates a ranch where he raises horses and livestock. He has authored several fiction and non-fiction books, including Understanding Equine Lameness and Understanding The Young Horse, published by Eclipse Press and available at www.exclusivelyequine.com or by calling 800/582-5604.
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