by Heather Smith-Thomas

Sometimes after foaling, the mare experiences problems. These situations can range from mild and temporary to serious and life-threatening. Jennifer Davis, DVM, PhD, DACVIM, DACVCP (Clinical Assistant Professor, Equine Medicine and Clinical Pharmicology, North Carolina State University), sees a lot of post-foaling problems at the university animal hospital.

RETAINED PLACENTA - This is one of the most common complications after foaling. "In mares, it's a little different than in ruminant species like cattle (cows can safely retain the placenta for several days with no ill effects, for instance). In mares, if the placenta is retained as long as 3 hours, they need to be treated. Any time a mare has a placenta retained more than 3 hours, there is possibility that she could start absorbing bacteria and toxins from the uterus, become systemically ill, and show signs of endotoxemia, which can lead to shock and laminitis," says Davis.

"Retained placenta should be treated aggressively with Banamine as an anti-inflammatory agent, and antibiotics. We may attempt to get the placenta out, but that can be fairly difficult if it's adhered tightly. Mare owners should not pull on the placenta; if they break off the part that's visible, it is harder to remove the remaining internalized tissue. Usually what we do is try to weigh down the external tissue. We'll put a wrap on it, which will get wet and heavy, and provide gentle, steady tension on the placenta to help it come out," explains Davis.

"Another thing the veterinarian might do is try to distend the placenta with fluids. This can often break the seal between the placenta and the uterus, providing the placenta is intact and the fluid isn't just going directly into the uterus. Other than this, it's usually just a matter of patience and gently teasing it out over several days--but this is not something we advise mare owners to do," she says. If part of it breaks loose and leaves a piece or pieces in the uterus, this can be a serious situation.

"When it comes out, we want to make sure the whole placenta has come loose. It needs to be examined by a veterinarian to make sure that it's intact, with no piece(s) left inside. If a piece stays in there, it acts as a nidus for infection. Even if the whole placenta does come out, the mare may have a bit of endometritis or a metritis, where there is infection in the uterus that needs to be treated with antibiotics and flushing, by the veterinarian."

She sees a number of side effects from retained placentas, the most common being founder. "This can be very devastating to the mare, so we try to get on top of this as quickly as we can. We'll often administer some preventative medication if a mare is being treated for retained placenta. We'll keep her in a heavily bedded stall and put wraps on her feet. Sometimes we ice the feet, or give medications to help maintain blood flow to the feet. We make sure there is enough padding to keep them comfortable and not bearing too much weight on the toes," she says.

"Sometimes these mares need IV fluid therapy, particularly if they are showing signs of endotoxemia. It can be fairly difficult to treat them, and sometimes they need hospitalization--especially if the placenta hasn't passed within 24 hours of foaling. Making sure we get everything out, and that there is no infection left in the uterus, are key things, since this can impair the mare's ability to rebreed. She may miss a season, or she may develop scarring in the uterus and have permanent fertility problems. So for a broodmare, whose only job is to produce babies, this can be very devastating," says Davis.

"Retained placenta can occur with a normal foaling, but is more common after a difficult birth, which can also imply that there might be something wrong with the baby, so it's also a good idea to keep a close eye on the foal--in case there are more problems than you actually realize. Any time a mare foals, the placenta should be examined thoroughly to make sure there are no areas of infection, thickening or any other abnormality." Even if the birth seemed perfectly normal, the placenta should be examined.

In some cases it may be heavier than normal, which might mean the tissues are thickened--which is seen with fescue toxicity. "The placenta changes in later pregnancies as a mare gets older. The uterus gets more and more abuse as the mare has more foals," says Davis. If you have any questions or suspicions about the placenta, it's always a good idea to have your veterinarian check it. Many mare owners routinely save the placenta to have their vet look at it when he/she comes to check out the new foal and the mare. You can put the placenta in a plastic bag and put it in your refrigerator until the veterinarian arrives, suggests Davis.

Sometimes it can be difficult to check the placenta, if you aren't right there when she sheds it and the neighborhood dog runs off with it, but if possible it should be checked. You want to make sure everything passed and nothing is left inside the mare. "Sometimes just the tip of one horn is torn off and stays in the uterus, and can set up an infection--which may not be recognized until too late to head off a long-term problem. If this problem is noted, you could immediately start flushing the uterus and put the mare on systemic or intra-uterine antibiotics," says Davis.

UTERINE TEARS - On occasion the uterine lining or wall may be scraped or torn, especially if it's a difficult birth and the foal had to be pulled or is really large for the size of the mare. "A tear can be difficult to diagnose. What happens is the uterine fluid starts to leak through the tear into the abdomen. You don't see anything unusual at first because the abdomen is very large and it may take awhile for the fluid that's leaking in there to set up infection and for the mare to show signs. She'll get a fever and go off feed, and show signs of colic and depression. It can be extremely serious; there may be fibrin forming in the abdomen, which can lead to adhesions between the intestines, and the mare becomes prone to chronic colic," says Davis.

"Overwhelming sepsis can be life-threatening. For the immediate future, this is what we worry about first. The mare can get very, very sick. There's no real way to sew up the uterine tear except to take the mare into surgery. Even this is not always successful since the tear may be difficult to access. But sometimes you can treat the infection and keep it under control while the uterus heals itself. Thus it's much better if it's a small tear, and you catch it early and treat the mare," she says.

"Sometimes we have to put drains in the abdomen and flush the abdomen from the outside. It can become very complicated, so you want to avoid this if possible. Anytime there's a dystocia (difficult birth) or the baby has to be pulled, it's wise to have your veterinarian take a feel of the uterus after the foal is delivered to see if everything is all right. This can be difficult to determine, however, because most people's arms aren't long enough to feel to the end of the horn that the baby was in. Once the uterus starts to come back to normal size, it folds back in onto itself so it can be very difficult to diagnose these tears after the fact," she says.

"As a referral hospital, we don't often get to check the mare until there is actually an infection in the abdomen. Then we do an abdominocentesis (sticking a needle into the abdomen and sampling the abdominal fluid) and find increased white cells and protein and sometimes red cells. We can also insert an endoscope into the uterus and look around. The tear can be hidden in one of the folds, but the endoscope is a little more successful, many times, than trying to get your arm far enough in there," she explains.

"Some people recommend filling up the uterus with a sterile dye, then looking to see if it shows up in the abdomen. In my experience, however, this test isn't often successful just because of the volume that you have to put into the uterus to fill it up. To actually be able to detect a color change in that much abdominal fluid can be difficult. I haven't had much luck with that. I mostly try to diagnose the problem by manually feeling a tear in the uterus or being able to see it with the endoscope," says Davis.

"This is a very life-threatening problem when it happens, and if the mare does survive, the torn area may scar down and prevent her from carrying pregnancies in that horn in the future–if it's a big enough tear. If she is bred again, you are basically cutting your chances to have her become pregnant in half. Most of the time, what we are worrying about is just saving the mare. If she survives, then we tell the owner that she may not be the best broodmare prospect. Most of our clients just want the mare saved, so we do our best," she says.

The mare may be systemically ill and at risk for laminitis and other complications that could also be life threatening--or career ending if the owner wanted to ride her. "Breeding is a dangerous business! What we see here are usually the disasters," says Davis.

POST-PARTUM COLIC - "There are a couple specific types of colic related to pregnancy and one of these is colon displacement or torsions. What happens is that the abdomen has been filled with this huge baby, and now it's gone and there is suddenly a lot of empty space. The colon can get gas up and then get out of place or turn over on itself. Things start to twist. Occasionally, displacements can be treated medically, but colon torsions are surgical cases and are fairly difficult to treat," she says.

"If the colon starts to lose blood supply (the twisting shuts off blood vessels) it can become very compromised and leak toxins and bacteria into the bloodstream. It is very difficult to actually remove all the colon. It's a very expensive process and the animal tends to have more complications than if we were to remove a piece of small intestine because they lose the ability to absorb water." The colon is where the remainder of any fluid in the digestive tract is resorbed before the balls of feces are formed, to be passed on out. With the colon removed, the horse may have problems with chronic diarrhea," she explains.

"Fortunately, torsions are a little less common than actual displacements after foaling. Displacements tend to do very well. Most of them are surgical, but some can be treated medically--with supportive care, lots of fluids, and a little pain relief. If the colon is not displaced too far forward, and we can get the mare moving and restore some motility, things may straighten out and she will be able to start moving things through again," says Davis.

"Sometimes we just get lucky; about 20 to 30 percent of the displacements we see in here we are able to treat medically but the rest of them have to go to surgery. This usually depends on how distended they are with gas, and how painful. One thing we worry about with colicky mares is that they might hurt the baby." Some mares will be in such pain that they will throw themselves down and this may injure the foal.

"This doesn't happen very often, because most experienced broodmares pay attention to where their babies are at all times. They are very focused on the foal, even to their own detriment. They tend to take care of the baby and worry about it and may not show as much sign of colic as other horses. They are being overly protective of the foal and don't want to get down and roll, like they would normally. Sometimes this can delay our diagnosis."

She says another thing that sometimes happens is that if there is a retained placenta or some fluid in the uterus that needs to be flushed out, the mare is often put on oxytocin after foaling. The oxytocin therapy can make a mare act a little colicky, just because it stimulates the uterus to contract more. "These contractions can be painful, and people think that the colic is due to the oxytocin when it may be due to an actual intestinal problem. This can mask the picture. If the mare gets colicky we usually stop the oxytocin therapy for a couple of hours to see if the signs of colic resolve. If the colic is due to oxytocin the signs should resolve fairly quickly. If colic persists, the mare needs to be treated," explains Davis.

"The other type of colic involves bruising of the intestine. The foal in the uterus sits on a piece of intestine for awhile, and this pressure can actually bruise the intestine, causing a little hemorrhage in its wall. Any time that happens, this can stop the motility of that piece of intestine. The one we worry about the most is the cecum. It is located on the right side of the abdomen so it usually only happens with right horn pregnancies," she says.

"If the bottom part of the cecum gets damaged, food can start building up in there, filling the cecum. It gets bigger and bigger, and the problem with this is it's a very distensible piece of intestine so you don't really know this is happening; the mare doesn't show signs of colic until it gets very distended. She looks fairly normal, but has this huge impaction in the cecum, with gas or fluid building up in it," says Davis. The mare might not colic until the very end, when the cecum is about to rupture.

Even though the bruising takes place before foaling, you generally don't see any signs until after the mare foals. "We don't know if that's because food can't really build up too much in there with the foal sitting on it--and it really can't start to impact until the mare foals and there's more room--or whether it's starting before she foals but is just a mild problem that is building up by the time she foals. We usually see it in the first week or so after foaling," she explains.

"Cecums can get very large and you may not notice any signs of problems until they are about to rupture. We've had a couple rupture just from this buildup. If fluid therapy isn't helping and painkillers aren't controlling the pain, the mare sometimes needs to go to surgery to have the impaction removed," she says. Successful outcome, however, depends on how much of the cecum was compromised during the pregnancy. This will determine whether or not it will start moving again.

"The cecum is another piece of intestine that is difficult to remove. If the problem occurs up near the top of the cecum you can't really get to it in surgery. You can bypass the cecum, which may prevent future impactions, but this still does not allow you to remove any compromised tissue. This can be a life-threatening problem for the mare after foaling. Usually the first clinical signs (that owners should look for) are decrease in fecal output-- less than 5 piles per day--and what the mare passes is often smaller than normal piles," she says. Sometimes the manure is firm, but in some cases it can actually get too soft because not much can come through the impaired, partially blocked cecum except liquid. The mare may have diarrhea--the fluid that can move across the top of the impaction.

"With any horse we have here in the hospital, we monitor how many fecal piles are produced every day. If it gets below 5 piles, we do a rectal exam and possibly tube the mare with oil to see if that comes through--although they can pass oil and still be blocked in the cecum. This is something owners can do at home, however, after a mare foals, monitoring how much feces she is producing. At that point she should be eating a lot (to produce milk) and passing a lot of manure," says Davis. It is usually pretty obvious when a mare develops decreased fecal output.

"Sometimes we get fooled because a mare is passing a normal number of piles, but when you actually examine the piles you find they are smaller, or they are too dry or too loose," she says. If things don't seem quite right, you should have your veterinarian check the mare. It's always best to check.

HEMORRHAGE AFTER FOALING - Though it's more common in older mares that have had many foals, uterine artery ruptures can occur in any mare after foaling. "We've also seen ruptures of other arteries, like the internal pudendal and caudal uterine artery, which are a little different because they start to bleed out the vagina, rather than into the abdominal cavity. Either one of these situations is a life-threatening problem. A lot of them present with signs of colic, rather than hemorrhage, but we can usually be pretty suspicious, based on simple blood tests. A PCV measurement will tell us if the mare is losing red cells and protein somewhere--most likely into the abdomen," she says.

"Then we can do an abdominocentesis (sampling the fluid in the abdomen) and see if there's hemorrhage. It's not abnormal for a mare to have a slightly red tinge to the abdominal fluid after foaling, just because of everything that was going on, particularly if it was a difficult birth. So what we do when we get that sample, if we are worried about a hemorrhage, is run the same test on it that we do on the blood, to look at the percent of red cells and protein. If it's starting to approach what normal blood would be, we know there is blood in the abdomen," explains Davis.

"Sometimes the veterinarian can actually palpate the hematoma (blood clot), particularly if it's contained in the broad ligament that supports the uterus. It feels like a hump. Anytime you feel that, you want to come right back out, very carefully, and try not to disturb the clot," she says.

"If it's a ruptured uterine artery, usually the only effective treatment is to put the mare in a stall and keep her very, very quiet, and let nature take its course. You want to keep her blood pressure low. Sometimes we'll give her acepromazine because this can decrease blood pressure as well as keep the mare calm and quiet in the stall, however this may exacerbate signs of hypovolemic shock. If it's a rapid blood loss and the PCV gets really low, the mare may need blood transfusions, but doing that may increase the blood pressure, as well. It's a tricky balancing act. Sometimes the mare needs oxygen therapy. We'll also put her on antibiotics, because having all that blood in the abdomen provides a great medium for bacteria to grow," says Davis.

"On more rare occasions, a mare may rupture other arteries and actually bleed out the back. Once that happens, she may rapidly bleed to death. If bleeding is into a cavity like the abdomen, eventually it fills up and starts causing back pressure (there's no room for any more blood). This puts pressure on the bleeding artery and helps stop the bleeding. But if a mare is bleeding externally (from the vagina and vulva) there is no good way to stop it. It is fast and dramatic, and usually fatal. With the ones I've seen, we haven't been able to get them to stop bleeding. Fortunately, however, this is a lot more rare than the other artery ruptures," she says.

"Sometimes the mare is so colicky that she gets taken to surgery before anyone realizes what the actual problem is--without actual diagnosis. Once we get in there, we're obviously increasing the chance that whatever clot was starting to form will come loose and she'll bleed again. So any time we have a post-partum mare come in for colic surgery, we check the abdominal fluid before she goes to surgery, and do a good rectal exam to see if we can feel the broad ligament to see if she's hemorrhaging. We try really hard to avoid taking these mares to surgery. If they have continuing pain that you can't ignore, there may be a couple things going on here," explains Davis.

Colic in a post-foaling mare can be very confusing and needs an accurate diagnosis. There is often some kind of cramping after foaling and the mare doesn't feel well, so it can be difficult to determine if there is a serious problem or it's just normal post-foaling cramping. It's always a good idea to have your vet examine the mare to find out if this is something serious or not. "We recommend that owners have their veterinarian come check out the foal and the mare, at least within the first 24 hours, to make sure everything is going all right," she says.

DISCHARGE - Some owners get worried if the mare shows a discharge from the vagina a few days after foaling. "This is generally normal, if the discharge looks bloody and then turns brownish, and then starts to get clear again," says Davis. This is the mare's normal flushing of debris from the uterus after foaling, sloughing some of the material from the uterine attachments for the placenta, etc. This is a normal process called lochia.

"We tell owners that this will be happening (if this is their first foal) and not to worry too much about it. Take the mare's temperature when you see this discharge, to just make sure that it's not an infection. If she has a fever, the discharge may indicate something else is going on. If it's just the normal lochia, she should not have a fever at all," says Davis.

It can take awhile for signs of infection to show up after foaling. "An infection in the uterus may take a few days before it produces a discharge. It may appear about the time that the normal lochia starts, so you want to be able to tell which is which. The lochia will be brownish-red, whereas an infection will produce a thick, yellow discharge like pus, with quite an odor to it, and often accompanied by a fever," she explains.

VAGINAL TRAUMA - This can also be a problem post-foaling, with recto-vaginal tears, if the foal puts a foot through the birth canal on his way out--creating a hole between the vagina and the rectum. "These tears are usually not life-threatening, but if there is a big enough hole, feces from the rectum can gain entry to the vaginal vault and increase the risk of infection in the uterus, particularly right after foaling when the cervix is still dilated. Usually we don't repair these tears right away," she says. You wait for swelling to go down, and for a nice healthy bed of granulation tissue as the wound starts to heal.

"But this is certainly something that your veterinarian needs to be on top of. We usually put these mares on stool softeners to make sure they continue to pass manure and don't become impacted, since the act of passing manure is very painful. We try to keep them on soft feed like Equine Senior with some water mixed in, and green grass (if there is any). We often tube them with mineral oil or other stool softeners to make the manure easier to pass." Green grass is ideal, but it can be hard to keep enough weight on a lactating mare without feeding her some additional forage such as hay, but the latter can often cause them to impact," she says.

"Usually, even if you sew up the tear right away, it tends to break down quickly, and you have to go back in awhile later and sew it up again. These can be difficult surgeries, simply because it is difficult to access the tear. These are often done standing, with the mare sedated and given an epidural (spinal block) to keep her from straining while the suturing is being done." Just the presence of anything in the vagina or rectum will stimulate her to strain.

"It's not an easy surgery, and it often takes several times before you get the whole area closed up because once the epidural wears off she has to pass manure and is straining, and then it's a contaminated area and there's chance for infection, or abscesses, forming at the suture line. These cases can be difficult to manage and get healed up. Usually as long as the tear is toward the back, it's not a life threatening condition. What we'd worry about would be if the tear went forward--particularly in the rectum--and actually communicated with the abdomen. This doesn't happen very often, however. The area of the rectum that is usually affected is farther back and does not communicate with the abdomen," she says.

"This area can be traumatized after foaling. We see a lot of vaginal bruising where hematomas form in the wall and there is lots of swelling. Usually these are not life-threatening and do not affect long-term fertility, but can be very painful. The mare may require some pain-killing drugs just to make it easier for her."

Some mares tear at the vulva, particularly if it's a first foal and the foal is a little large. "Usually we just sew these up. As long as it doesn't communicate with the rectum, those can be done within a couple of days after foaling (after initial swelling subsides)," says Davis. Sometimes these tears will heal on their own, but if the tear is off to the side and isn't stitched shut, the vulva may develop a little hole there that interferes with proper closing of the vulva and increases the risk of infection entering the reproductive tract.

"We usually try to sew those up fairly soon, and they heal very well. You want to try to get it to where the vulva has normal structure and everything closes properly. Tears can happen inside the vagina as well, but usually we just let those heal on their own. We keep them clean and sometimes put an ointment into the vaginal vault while they are healing. These tears don't typically cause a problem," she says.

"What can cause problems is if the cervix is torn during foaling. This can be very difficult to repair. Most veterinarians don't try to sew these unless it's a full thickness tear; in that case it would communicate with the abdomen and be very similar to a uterine tear. If it's just partial thickness tearing, we'll often let it heal on its own. It may create scarring, however, and then the cervix can't close properly, and the mare may be infertile, with chronic infection in the uterus and chronic drainage. These are all things to look for, and at least with cervical tears they are easy to palpate and can be checked right after foaling when the cervix is still dilated. This is something your vet would hopefully take a look at during a post-foaling exam, the first visit after foaling," says Davis.

The opening from the bladder is in the vagina as well, and on rare occasion this area becomes torn or bruised. "Or if there is infection in the area, it could spread up into the bladder, but this is very rare," she says.

VAGINAL OR UTERINE PROLAPSE - This is when the mare strains so much during the birthing process that part of the vagina or uterus protrudes through the vaginal opening. If it is just the vagina, medications can be given to stop the straining, the tissue can be replaced, and a Caslick's repair performed to help keep it in place. If it is part of the uterus prolapsing, this is much more difficult to replace and tends to recur. If a sufficient amount of uterus is prolapsed, it can cause tension on the broad ligament and uterine arteries, which may then rupture and cause severe hemorrhage as described above. The externalized tissue is also highly prone to infection and contamination from the environment.