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Spaying a mare

From: Peggy

Dear Jessica, Well, I guess it is my turn to ask you a question. You have been the source of so much wonderful information, but more than the facts, you infuse all your thoughtful replies with an abiding respect of the horse, the person and their respective welfare. Thank you for being there for all of us. A few months ago my 6 year old mare starting showing some changes in behavior. She would nicker and bow her neck at mares as she walked down the corral aisle. From being "one of the girls" she became the dominant horse in her pasture. She became very interested in manure on the trail. Anyway, the vet found what she thinks is a granulosa tumor on her ovary on palpation and suggested a blood test to confirm hormonal changes. She mentioned that surgically removing the tumor would be an option and that her other ovary would then return her to normal cycling, and, if desired, she could be bred. Other folks have suggested that she just be spayed. I have questions about the effects of spaying on her. There are mares that I believe spaying would be a kindness, especially in these circumstances where surgery is happening anyway. This mare, however, did not have hard cycles. Her behavior stayed fairly consistent. I have a preference for mares to ride, as I find them in general alert, careful and responsive as compared to geldings, in general. My first thought about spaying her was, "no", but now I'm reconsidering. I found an article by Cherry Hill which states that she will still be mare-like although obviously not breedable. I have no intention of breeding this mare. My vet says in his experience with spayed mares that it is a "wonderful" option and that all people have been pleased with the results. There are significant differences in behavior and way of being between a stallion and a gelding. What is the difference between a mare and a spayed mare? Is there a name for a spayed mare? I'm researching the alternative types of surgery and what is available in our area. I'm finding information about these questions but not about the effects of spaying on her being and behavior. Thanks so much for your help.



Hi Peggy!

The spaying option is indeed becoming more common, and sometimes it's a useful solution to a chronic problem, but you should be aware that there is no absolute guarantee that spaying will create the changes that you want to see in your mare. That said, the chances that it WILL create those changes is very high. I'm sure that you've discussed this at length with your veterinarian, and possibly even gotten a second opinion. Since I'm not a veterinarian, I probably can't add much information to what you've already learned from various veterinarians. From the point of view of a horse trainer, though, I can tell you that spaying is a much more common surgery than it once was, and that it's neither as invasive nor as expensive as it used to be. If you haven't already done this, talk to your vet about the various surgical options: abdominal, flank, and vaginal.

All the equine vets I know agree that ovarian tumours are probably the #1 reason to spay a mare. Mares that are exhibiting dangerous and/or stallion-like behaviour typically become good citizens again shortly after the granulosa tumours (or tumours and ovaries) are removed. If you're not intending to breed a mare, and she's suffering the effects of such a tumour - or even just suffering the effects of a painful follicle every few weeks - spaying the mare may be a very good idea. Like the colts that are gelded during their racing careers because they aren't able to settle down and focus on their jobs, mares (whether at the racetrack or in the competition arena or just riding fence on the home ranch) can become re-focused and enjoy their lives again when the hormonal surges and pain are no longer a factor.

Although I can't tell you anything new about the surgery itself, I can tell you, again from the horse-trainer's viewpoint, that you can safely have her ovaries and the tumour removed - you won't end up with a gelding, you'll just have your mare back, only comfortable and without the hormonal imbalance that's been changing her behaviour. She'll be more consistent, but it won't change her personality or give her a new personality, it'll just let her be her best self - the mare you already know - more of the time. Don't worry about your mare becoming a different horse after the surgery. I know that some people worry about this, but they shouldn't. After the surgery, what you'll get is your OLD horse back, the way she was before the tumour began affecting her hormonal balance and changing her behaviour.

The only option that NOT spaying will leave open is that of breeding her, which isn't something you were planning to do anyway, so I would say that you really have nothing to lose and quite a lot to gain. Mares don't get placid or fat after being spayed (unless you feel sorry for them and overfeed them!). They just get back to being themselves, whatever they were like before the tumour appeared... Almost all of the spayed mares I've seen have been just great afterwards, and their owners have been very happy with the results. The single exception was a mare that had attitude problems for other reasons, and was in pain (all the time!) that had nothing to do with her ovaries. Her owner chose to blame the mare's behaviour on "being a mare", and insisted that the mare be spayed to "fix her attitude". Since her attitude wasn't the result of an ovarian tumour, and this mare was an unhappy, nasty-acting mare when she went in for the operation and she was still an unhappy, nasty-acting mare ten years after the operation. It didn't change anything - other than making her infertile (which was just as well). But that was a case of the surgery being performed for the wrong reason. It sounds to me as if you're looking at surgery for the RIGHT reason.

Still, it can't hurt to run down a short checklist of possibilities before you take her in for surgery. You have probably already done these things, so I mention them here for the benefit of other horse-owners who may just be starting to think about the possibility of spaying a mare. I always like to look at the whole horse - that's what Holistic Horsemanship means, after all: dealing with the total horse in its total environment! Some mares exhibit behaviour problems that have nothing to do with tumours, ovaries, or hormones; some mares with verified uterine tumours never exhibit any problem behaviours at all. If a normally sweet-natured mare is becoming steadily more unpleasant, AND the mare's behaviour problems are caused by an ovarian tumour, then removing the tumour and/or the ovaries may very well end the problems and restore her original sweet nature. But it's a good idea to investigate ALL possible causes for behaviour problems before opting for surgery. Check ALL the possibilities, ensure that (for example) your mare's hooves and teeth and back are not causing her pain, discuss the situation with your veterinarian, and then make your decision. If the tumours are causing the attitude change, it's worth the expense and risk of removing them to get your sweet mare back again.

By the way, if there's a special name for a spayed mare, I'm not familiar with it - but if it exists, I'll bet someone will tell me shortly. ;-)


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