Can a bred mare come back in heat?

[lilpondarosamini]

I had someone ask me if a mare bred on the foal heat could come in heat a month later if she was already bred. They said after the second heat the mare never came in again so their not sure how to calculate the impending birth. I told them to count from the second breeding. Is this the correct answer?

[onthedeck]

Pregnant mares can show heat even though pregnant. They are not "in heat" but just show signs. If your friend did not ultrasound to confirm pregnancy, she should everytime she breeds to check for twins, etc. There is always the chance the mare slipped the pregnancy & is now open also. Don't ever assume a mare is pregnant just because she did not come back in, always check via ultrasound.

[Heather T]

Yep - I'm with Onthedeck, especially if this is a mini mare. Tess is due at the end of this month, and Lily is due this month (or next ) as well and they both show to our stallion. I think it's hormonal. We had them both confirmed in foal last month.

[lilpondarosamini]

Thanks I will e-mail her and let her know.

[onthedeck]

Forgot to add...I have a mare who shows heat through her entire pregnancy. Makes the early part of her pregnancy nervewracking until she begins to show.

[risingrainbow]

Normally, but not always, if a mare is bred when she is already in foal but showing heat, she will abort the pregnancy. There have been instances however of mares that have retained the pregnancy and gone on to produce full term healty foals.

In the vein of what's best for the mare, most modern reproductive specialists advise against breeding on the foal heat. The belief is that the mare needs that heat cycle to further clean out her reproductive tract and to have time to recover from the pregnancy.

[mythicfriesians]

I also have a mare that shows heat through her entire pregnancy. And she NEVER actually looks in foal, even the day she pops the baby out, so it is nerve wracking for 11 months!

I'll second what risingrainbow said - there is very little chance, if the mare actually was pregnant after the foal heat, that she would have retained the pregnancy if they bred her the second time she showed heat. Also, just because she didn't show heat again after that doesn't mean she got pregnant from either breeding.

TECH DETAILS (NOT for those sensitive about body part discussions!):
When the stallions breeds the mare, the tip of his male thingy actually goes through the cervix in to the uterus. If the mare is pregnant already, that should terminate the pregnancy immediately. It also means she can NOT catch on that second breeding, as she wouldn't be ovulating when she is already pregnant.
I would think that the only way that breeding a pregnant mare would not terminate the pregnancy is if the stallion didn't penetrate deep enough to open her cervix, which certainly can happen.
END TECH STUFF

I would say that your friends need to palpate or ultrasound the mare to find out if she is pregnant - and if she is, it was almost definately from the second breeding.

[risingrainbow]

I have one of these sneaky mares too that show to the stallion while she is in foal and doesn't really look like she is in foal until the very end. At the nine month mark I'm always shaking my head and wondering whether she is or isn't still pregnant.

I've been told that mares that far along shouldn't be where they can tease the stallion because that behavior can cause them to abort. But I have never see any proof that is the case. My barn with my stallion in it sits right in the middle of the field and the mares can all come right up to Legs and visit with him at any time. They are all great friends and love to spend time visiting with him even when they are pregnant. He is sweet and grooms on them and respects them telling him they just want a little attention but no hanky panky.

He also gets to visit with his babies this way and he is very tender with them. It is fun to watch them nuzzling him and him rubbing his head against them in what looks like a caress.

[Steph @ Elements]

We have a mare who will tease the stallion and even let him BREED her even though she is already pregnant. The difference being that hormonal influences from the fertilized egg will keep the cervix closed tight, so even though the stallion may mount, nothing is getting into the cervix. We TRY to avoid this happening anyway, and you never know when things might chage and the mare might lose a pregnancy, but allowing a stallion to cover her just one cycle after getting pregnant is not unheard of at all.