This is Not Possible! Right?

Oh no! I sure hope he doesn't have a retained testicle. The last thing that poor old girl needs is to get pregnant again.   Can you check with the people you bought him from to make sure that both testicles were removed when he was gelded?

Interesting! I wonder how a vet can check for that. Maybe x-rays? It's interesting that the mare was mounting her as well, something going on with the mare being mounted by everyone, maybe a hormone issue?

Hi, nhg.
Mare mounting mare is not unheard of. I hadn't seen it, personally, but I'm being told it's nothing to worry about.
This is actually bringing back some very sad memories. A horse  I had in my late teens,(Dusty) ended up having a third testicle, talk about rare. I was able to visit with his original owner and the vet that gelded him. Long story short, we (my vet at the time and I) took him up to the university vet hospital. The surgery was very long and the vets closed him up, sort of, to try again from a different area, later. They didn't stitch him up, they packed him. After all was over, I was told that was common. Anyway, during the night he acted up and "by the time they got to him" the packing had come out, along with part of his intestines. He had to be euthanized. Wow, I'm getting teary eyed after all these years. Anyway, the vets were curious, and went back in (at no charge to me) and found the testicle next to his spine. I was told that through the years a testicle can move around and it wasn't the first testicle they had found in that area.
Dusty was a wonderful horse, I wasn't having any actual problems with him. But, others recommended that the testicle should go. I still wish I hadn't listened. That had to be so scary and painful for him.
For your question, a testicle is soft tissue, wouldn't show up in an xray. I wish they could have done something, to locate the testicle in Dusty. He wouldn't have had to die.
As long as this situation is the only "problem" I have with Cayenne, I won't be wanting to travel that road again anyway.

Testicles can be felt by palpation on abdominal cavity by your vet. So that way you can be sure if he has remaining testicle.

I am sorry, I dont understand english good sometimes.

No, you're fine. You're right for the vast majority of horses. I don't know how rare it is for a testicle to move. But then, in Dusty's case, a third testicle, who would have imagined that? After that experience I'm just too sensitive on the subject.
I promise to be careful! Since everything I've been hearing is that the "breeding" incident isn't all that uncommon I'm not going to get myself too upset. I will protect my mares and visit with the vet. Calmly.
Thank you for trying to be helpful, I know that was all you were doing. Your information is appreciated! smileys-flowers-548267

I know how it feeles, i have seen my horse dies. I still have nightmares from that. I am very sorry you have to go threw that.

How sad for you to go thru all those feelings of guilt about dusty and his surgery. yet again you only did what was suggested by your elders and others. not your fault, yet the feelings of being at fault never go away , they lay dormant and erupt when faced with a similiar situation. i know all to well what you are going thru. and i give you many .

as for geldings mounting and actually breeding. yes they can.
i have seen it happen and i know these horses are geldings that do not have a third testicle or have been proud cut.

perhaps a blood test to determine levels of tosterone.?? call your vet and perhaps suggest it.  

We have a very hot mare here. And when she cycles. She's a regular HO. She even had JR trying to mount her. He has never done that with any other mares. Even Rawhide mounted mares. But never penetrated. Never heard of a horse having an extra testicle. Wow...