Mares Mounting Mares

[Jess&Berry]

Okay something really odd happened today:

I was going to get my mare (Black Berry or Berry) from her field today (there is about 8 or 9 mares in the field) and everything was going fine when another mare trotted up to Berry and started striking at me... I was really confused so just stayed out the way and tried to hurry berry up. The the other mare began becoming very loud, almost like a stallion. I unclipped Berrys leadrope so that if she ran she wouldn't be lame and stood back... As I watched (from a distance!)the other mare was standing behind berry. Berry began squirting at her and then the other mare tried to mount her!!! I was so shocked because I had never seen this behaviour before? Berry is 16 and the other mare is 7. The other mare was a rescue so I don't know wether that would matter but has anyone else seen this kind of behaviour in mares or know what was going on??? Thank you!

 

[JanetGeorge]

Almost certainly a hormonal imbalance in the 'stallion-like" mare. Possibly a granulosa theca cell tumour on the ovary. It's a benign tumour - but results get worse & worse as it grows because it exudes testosterone. The owner should be advised to get the mare's ovaries scanned (but if like a LOT of owners - will probably take offence and ignore you, lol!)

 

[Jess&Berry]

Thanks for the help xx

 

[Follysmum]

A few years ago my pony started mounting her mother and behaving very stallion like. Was very much out of character for her as she had never displayed this behaviour before, she was perfect to ride. I put on her some oestress for the summer months which seemed to help. Never had this problem again with her.

 

[Sukistokes2]

http://americashorsedaily.com/a-horse-health-puzzle-mares-who-act-like-stallions/

Interesting reading

 

[JanetGeorge]

http://americashorsedaily.com/a-horse-health-puzzle-mares-who-act-like-stallions/

Interesting reading

A useful article. I'd forgotten about hermaphrodites - never had it in a horse bbut had it in a lovely Charollais ewe lamb - real tragedy!

And of course if it's a recent rescue, it MIGHT be pregnant.

 

[Mahoganybay]

Almost certainly a hormonal imbalance in the 'stallion-like" mare. Possibly a granulosa theca cell tumour on the ovary. It's a benign tumour - but results get worse & worse as it grows because it exudes testosterone. The owner should be advised to get the mare's ovaries scanned (but if like a LOT of owners - will probably take offence and ignore you, lol!)

This is super advice and one I recall JanetGeorge advised me when a number of years back (yes, have been on this forum that long, oh dear) I posted about my mare mounting other mares in the field.

I did indeed call the vet, who came & scanned my mare, she thankfully did not have a tumour, I did however, put her on Oestress which seemed to calm her seasons down a bit, but she did remain quite a 'riggish' mare.

 

[MyBoyChe]

The only time Ive ever seen this happen, the mare doing the mounting was indeed pregnant, unexpectedly as it was thought she was barren!

 

[Gloi]

I had my mare and stallion out together years ago and she was in foal with perhaps two or three months to go and she took to mounting the stallion. He seemed to enjoy it because most of the time she bossed him away if he got near to her. She stopped doing it after a few weeks.