Stopping a mare horsing!

[Sophie - L]

Hi!
Can anyone tell me if there's any operation/something that can stop my mare seeking out stallions like she does! She's like a heat seeking missile! This is the second time in 2 years she's suprised me and i don't want it happening again! I know they can't be neutered like oher female species but is there anything i can do?! Sure i heard something about inputting a small bead or something into the mare to make her think she's in foal.
Can anyone tell me if this is true? Pro's and cons etc. Or suggest anything else.
Thanks!

 

[Thistle]

You can use regumate or get a marble inserted. First I would be looking at fencing. If your mare is getting out and finding stallions then your fencing is obviously inadequate.