So a couple of weeks back I was asking if anyone had ever dealt with a stud that hadn’t dropped (cryptorchid horse).  I took my 7 year old stud to the new vet and he wanted to see if he could cut him the traditional way before we did anything major such as surgery.  So he goes in to remove the testicles, but there aren’t any.  He comes and talks to me about the horse, he said his penis is roughly around 3 inches long and there are no signs of testicles that he can see.  So we decide to do a testosterone test on the horse before he does a laparoscopic surgery.  The test come back with low testosterone, basically that of a gelding, he calls me and ask me if anyone could have gelded my horse,  nope, I have owned him his entire life and the trainer I use is a very close friend, and I tried to have him gelded before he even went to the trainer.  So the vet proceeds to talk about how the horse is built like a mare rather than a 7 year old stud and tells me about 5 other cases of hermaphroditic horses that he has seen over his 40 years of practice, but this case really has him baffled because of how the horse looks on the inside and how he appears on the outside.  So today we are running an estrogen panel on the horse to see if he is producing estrogen, and if so then I have to take him back to the vet to have an ultrasound done to see if he does in fact have ovaries and are they producing follicles, which would explain his behavior, instead of a hard headed stallion I probably have a moody mare, geesh I’ve already dealt with his momma and she is by definition the “chestnut mare”  .  So now I wait until Friday for the lab results to come back to find out if he is a she, or a she he, or whatever you want to call it.  All I know is I want my horse back to normal, he worked cows awesome and was on the barrel pattern and rode out great, fancy broke.  Now I have a nut job that I don’t know what to do with.  The vet reassured me would find out what was going on and that we could get him/her started on a regime to get things normal in his/her mind.  But everything on the outside of this horse says male horse.  Anyone else ever hear of such a thing.  I have heard of cows being this way only because there were possible twins in the wound and one absorbed the other.  But this is a first for me.  

All I can say IS WOW!!!!! Never had to deal with this problem befor in my entire life, this is mind BLOWING!!!! And very interesting, would love to see this horse, do you have any pictures of him/she?

We need pictures too.  Very interesting.

I'm sorry you're having to deal with this. I've actually personally seen this in one horse- the new owner purchased the horse thinking she was buying a mare. She had concerns about how she urinated, so she had my husband do an exam and it turns out the horse is a pseudohermaphrodite (and I believe this was the horse featured in this research paper by Dr. Tibary from WSU).

https://www.merckvetmanual.com/reproductive-system/congenital-and-inherited-anomalies-of-the-reproductive-system/intersex-conditions 

I've never seen anything like this.  I just wanted a colt out of the mare I raised.  She has been such a good horse, and an awesome barrel horse.  I had not intention of ever selling the colt or breeding him.  So now me, the vet and the techs are all curious to see how this turns out.  My husband told me, that it figures I would be a person that would end up having a horse like this, he said I have some of the strangest things happen to me.   

Well the vets office just called me and my 7 year old stallion is actually a mare producing estrogen. I have an appointment this afternoon to ultrasound her (this is gonna take some getting use to) and start putting her on some shots to stop her from producing follicles.  They are gonna monitor her for a couple of hours than I can come home and start the next serious of shots in 48 hours.  All I can say is WOW. 

At least you had enough sense to find a good vet and get answers.  Now, you can get her/him on the right track. 

Good luck.  This is very interesting and keep us updated. 

My daughter had something similar happen last year to her 4 year old mare. We bought her as a 2 year old from a friend. When the mare turned 4, started acting aggressive towards the others horses in the pasture and trying to mount them (didn't do this before) and biting them--bad. The mare also started to act more naughty on the ground--before she was a very well behaved horse. She would neigh at the other mares and would snort and smell where a mare went to the bathroom. Took her to a reproduction vet. Vet thought she felt very small ovaries. Wasn't quit sure what to do so she consulted with another vet at UC Davis. The UC Davis vet said to draw blood and test for testosterone and AHM. 

The test came back high for testosterone. The small ovaries were in fact small testicles. The vet was able to remove the testicles thru the rectum. The horse is fine now under saddle and on the ground. She is still aggressive (bites) the other horses in the pasture so my daughter keeps her separate as she boards. The surgery was done July 2019. My daughter plans on taking her to the vet and testing her testosterone again to see if it is still elevated & if that is why she is still aggressive in the pasture with the other horses and if anything can be given to he tor help with her behavior to other horses. 

Of course both vets offices were very excited. The local vet who did the surgery sent the testicles and results of blood work (they took blood work before the surgery and a few times after the surgery) to the vet at UC Davis as he was going to right a paper on the case. I should find out if he has completed the paper and see if I can get a copy.

The mare does have some estrogen also. When she is in heat, she will wink but no other behavior.

So to make a long story short, the mare is great to ride and work with on the ground and haul. She is still naughty with other horses in the pasture. 

The diagnosis and surgery was done at Northern Hills Vet in Sturgis SD. Margie Jones was the repo vet and Scott Cammack did the surgery. 

My daughter felt the same way, only she would end up with a horse like this. HA! 

Glad you kept at it to finally get and answer, hopefully you can get her all sorted out now that you know. Thank you for sharing this story, it's very interesting! 

She's beautiful 

My main thing is to know the horse is sane and want hurt anyone or itself.  The vet said that sometimes this happens when an older mare is given a regimen to keep her from aborting the foal, that the regimen can be given to long and cause this.  I told them the mare was never given any regimen only the 3, 6, 9 shots that the vet recommended.  The mare was breed along with 4 other mares, my colt was the only one that lived past the age of 2 months, all the other colts died.  The vet thinks it could have been something from the stallion, but the owner of the stallion had him cut after all the colts died.  The vet said he has seen 5 other cases but they have all been reversed, thought they were mares and found out they had stallion parts, he said this is the first case he has seen where the horse was thought to be a stallion but had mare parts.  Needless to say, the vets office is intrigued and excited over this case. 

Wow.  That is all I can say.  This is so interesting!  Thank you for posting updates.

The vet did the ultrasound and palpated my horse yesterday.  He found one ovary that was hard as a rock but he said the amount of estrogen that the horse is producing according to the lab work means there is another ovary in there somewhere.  He stated that nothing is where it is supposed to be in side this horse compared to that of a normal filly.  They gave the him/her a shot of lytalyse and I am to give him/her a shot of Altrongest Saturday.  He wants to see if the Altrongest makes a difference in the horse before we schedule a surgery to have the ovaries removed.  Meantime they lab is running a progesterone test and my vet is talking to a friend of his that is a surgeon at a University that has done a lot of laparoscopic surgeries on hermaphrodite horses, he said the problem he is having is that the cases he has done has always been a horse that was thought to be a mare that started getting aggressive and when they did the testosterone test it always came back high and the mare was actually a stallion and he would go in a remove the testicles and she would be fine afterwards.  He said this is the first case he has had that the horse was believed to be a stallion and was actually a mare and had ovaries.   He said he just wanted another opinion, and he also said that nothing about the inside of my horse is normal, that things aren’t where they should be, so this is another concern. He doesn’t want to go in and do an exploratory surgery (I strongly agree).  I don’t want to put my horse through anything more than we have to.  We did discuss if the surgery is the way to go that we will not do it until this fall.  We don’t want to do it with it being so hot and take a chance of infection with flies or anything else.  So until the surgery, if they Altrongest works, the horse will stay on these shots until we have the ovaries removed.

Very interesting.  I was wondering if there was any correlation to drugs/medicinal practices when this happens....

Very handsome/pretty