Dr. Robert Cope discusses the differences in uterine and vaginal prolapses in cattle
Two problems that sometimes occur during calving season are vaginal and uterine prolapses. Both are situations that must be corrected, but a uterine prolapse is more of an emergency.
Uterine prolapse occurs soon after the cow calves, while vaginal prolapses generally occur before calving – sometimes as much as several weeks – and can occur at other times of the year at earlier stages of pregnancy.
A calf has just been pulled. It was not that difficult. But the cow gives a few more strains, and out comes her uterus. Or your conducting pregnancy checks on new calves that were born unassisted, and find a cow standing there licking the calf, with her uterus hanging down behind her.
Prolapsed uterus’s usually occurs within a few minutes – to a couple hours after calving, while the cervix is still dilated, according to Dr. Robert Cope, Salmon, ID. If a cow keeps straining because of continued contractions and after-pains, she may push the uterus out. This can happen whether or not the birth was easy or difficult.
Cope explained that after the cow calves, the far end of one or both uterine horns may begin to turn inside itself. “This gives the cow the opportunity to push against it. To lessen the likelihood of uterine prolapse, I always try to get the cow up as soon as possible after pulling a calf. Getting her up and moving around will usually make the uterus drop back down in the abdominal cavity and straighten the uterine horns. Without a partially inverted horn against which to strain, it is difficult for a cow to prolapse.”
A prolapsed uterus is always a serious emergency, and a vet should be called as soon as the condition is discovered, unless you are experienced at putting this organ back in.
The forty-odd pound mass of fragile tissue hanging from the cow can be a life-threatening situation unless it is replaced quickly. If weather is cold, the exposed uterus serves as an outlet for loss of body heat; the cow may chill or go into shock and die.
If the cow happens to lie on, step, or kick the uterine tissue hanging past her hocks, she may rupture a major artery and quickly bleed to death. During pregnancy the uterus has a very large blood supply to take care of the developing fetus, and these large arteries can have nearly the size and pressure of a garden hose.
“When the uterus turns inside out, these arteries are on the inside surface of this large organ. If an artery ruptures, the cow may bleed to death within 5-10 minutes. By the time you realize what is happening, it is too late to do anything about it,” said Cope.
The inverted uterus is easily bruised, and will become infected if the cow is lying on the ground or if it becomes covered with manure. The cow needs antibiotics after the prolapse is replaced. She will more than likely have to fight off infection. The sooner the uterus is replaced, the less damage it will suffer, and the less chance for serious complication.
The veterinarian will probably give the cow an injection of local anesthetic when he begins the task of cleaning up and replacing the inverted organ. This will keep her from straining. The uterus must be thoroughly cleaned and washed, before it can be put back.
The next step is to keep the cow from pushing it right back out again. The vet may give the cow another injection of local anesthetic afterward to keep her from straining, or put a few sutures across the vaginal opening to keep the organ from being pushed out again, until the cervix has contracted and there is no danger of recurrence. The stitches can be removed in a few days.
If the uterus is not out very long, and is kept clean and undamaged until it can be replaced, the cow generally recovers. Most cows that prolapse will re-breed, and have no problems with the next calving season. Repetition of this condition is rare, so if she is a good cow, it’s usually worth the gamble to keep her.
Sometimes, however, the prolapse is followed in an hour or so by death of the cow, due to internal bleeding. The weight of the uterus hanging down can tear some of the tissues, rupturing major arteries. But in most cases, even when there has been bruising and contamination, the uterus will heal and the cow will fully recover.
Prolapse of the uterus should not be confused with prolapse of the vagina (a condition which usually occurs before calving, in the heavily pregnant cow). The vaginal prolapse is a pink mass of tissue about the size of a large grapefruit or even a volleyball, whereas the inverted uterus is a much larger, longer mass, more deep red, and covered with the “buttons” on which the placenta attached.
This is a common problem, and generally occurs before calving.
“Many things can cause a cow to strain until the vagina prolapses, including vaginitis (inflammation of the vagina), estrus, breeding, or the presence of the calf’s head or feet within the pelvic canal,” said Cope.
Some cows have a structural weakness of the reproductive tract that allows part of the vagina to prolapse during late pregnancy, and this is an inherited problem. Some bulls sire daughters that tend to prolapse, and they may pass this tendency to their offspring. Never keep a bull from a cow that prolapses, since some of his daughters will have this weakness. Cull any cow that proplases, and never keep a daughter from her.
Occasionally a cow will prolapse her vagina for other reasons, but the most common cause is from pressure and weight of the large uterus in late pregnancy. When the cow is lying down (especially if her hind end is downhill), this pressure may cause the vaginal tissue to prolapse.
Mild prolapses (a bulge the size of an orange or grapefruit) will usually go back in when the cow gets up. But if she starts to prolapse each time she is lying down, or strains a little while lying there, the tissues may be forced out farther, to the point they cannot go back in. Sometimes the presence of a mild prolapse will stimulate the cow to begin straining, making the situation worse. Then she has a mass of vaginal tissue bulging out, becoming damaged and dirty, and possibly infected.
According to Cope, the vaginal wall is not a sterile environment, so infection is not the primary concern.
“The main problem is that once these tissues are turned inside out, the returning blood supply from the prolapsed area becomes restricted, making the tissue swell. The longer it is left outside of the cow’s body, the more swelling that occurs, and the harder it becomes to replace. If the cow is near calving, this swelling may make the birthing process difficult. For these reasons, vaginal prolapses should be repaired as soon as possible, even though the condition is not usually life-threatening,” he said.
Some heavily pregnant cows strain when passing manure while lying down, or just from the irritation of a mild prolapse, making a small problem into a larger one. If the prolapse is large (volleyball size) the bladder may become involved; the urinary passage has pressure on it, the cow cannot urinate until the prolapsed tissue is pushed back inside. She may strain to urinate (unsuccessfully), aggravating the problem further.
If the tissue has been prolapsed several hours or longer, it will be covered with manure. It should be cleaned off before being pushed back, or irritation from contamination will cause inflammation and infection. Wash it gently with warm water and a mild disinfectant before pushing it back in. If a prolapse has been out for several days before it is discovered, the tissues may be dry and damaged, and harder to clean up and push back in.
Some cows prolapse every calving season during late pregnancy, even after the tissues are replaced.
To correct this problem, restrain the cow, clean up the protruding tissue and push it back in, then take several stitches across the vulva to hold it closed and prevent future prolapses. Umbilical tape is ideal suture material for this purpose – less likely to pull out than regular suture thread. A large curved surgical needle is best for making the stitches.
“The stitches should be anchored in the haired skin at the sides of the vulva. This skin is thick and tough and won’t tear out as easily as the skin of the vulva itself (and is also less sensitive and less painful for the cow when you are stitching). It usually takes at least three cross stitches to keep the vulva safely closed so the inner tissue cannot prolapse if the cow strains. She can still urinate through the stitches, but the vulva cannot open enough for prolapse,” said Cope.
If she is stitched, she must be watched closely as her time approaches to calve. The stitches must be removed when she starts to calve or she will tear them out, or worst case, have difficulty calving. When she goes into labor, stitches can be cut with surgical scissors, tin snips or a very sharp knife – whatever you have on hand to cut them with quickly and easily without poking the cow – and pulling gently out.
Once she calves, the pressure that caused the prolapse will no longer exist, and she generally won’t have any more problems until late in the next pregnancy.
Most ranchers cull a cow once she has prolapsed, because of the likelihood she will do it again next year. Offspring from such a cow should never be kept for breeding stock.