Hello out there
First sorry for my bad English, I hope you will understand anyway.
We are a group of students in Denmark, we are writing a report about mare-ish/mare-like bahavior, during their mareheat periode.
Therefore we would like to hear your experience with the problem, and how you treat it?

A change in a mare's behavior while she is in heat differs widely among different horses. Much like human females expierence different symptoms and to varrying degrees when they are fertile. Personally, I have delt with mares when you honestly could not tell when they were cycling all the way to mares who wouldnt let you on their back if they were in heat. Most fall somewhere in the middle. My expierence has been that mares in heat are just more irritable in general, wheteher it is pinning her ears at other horses in the show pen to pin-wheeling her tail at a spur.

Hope this helps,
bethany

The complete estrous cycle in the mare is about 21-22 days long. Actual "heat" or estrus averages 5-7 days, although it can range from 2-11 days. During this time the hormone estrogen peaks and mares become receptive to stallions. After ovulation, mares go out of heat for 14-16 days while under the influence of a different hormone, progesterone. Mares that do not seem to cycle properly or that become dangerous during estrus should be examined by a veterinarian to rule out medical problems. A veterinarian can also prescribe Regumate, a man-made form of progesterone, which can be given orally to mares for up to 15 days in a row to suppress estrus and the behavioral changes that can come with it. Several herbs are used to support a healthy and balanced hormonal system in the mare, such as Vitex agnus castus and Raspberry leaf.

You should carefully review their overall management to make sure that any behavioral problems are not due to improper diet, lack of turnout and socialization, poor ground handling skills, too little or too much exercise, ill-fitting tack, training and showing schedules, transport, or some other stress.

I wish this can help you.

Progesterone supplements really do work well!

I personally have had some very mare-ish mares. I have tried a few mare calming supplements with a bit of success.