[Equine Repro]

Well, as it's getting close to that time of year so I figured it might be a timely thread to address the question of a mare due date. I literally cringe when I see posts and questions worrying about mares that are "due" any day and mare owners discussing what they should do because their mare is "overdue".

The equine is unique in mammals in that the gestational length is determined by the fetus, NOT the mare. The AVERAGE gestational length is around 340 days. However, anything between 330 days and 370 days is well within normal!! Up until 370 days, your mare is NOT LATE!!! She is well within the range of normal gestation. Environmental conditions may often play a role in how long your mare goes, as well. For example, foals that are due early in the year, outside of what Mother Nature intended (January and February in the Northern Hemisphere, for example) will often have longer gestations. Foals that are born to mares that are dealing with placentitis will often undergo an accelerated maturation and will often be born earlier than that 330 date with no apparent repercussions, although they should be treated as if they were exposed to a pathogenic presence.

Foals that are born prior to day 320 days will often appear premature, have fine silky coats and may have other issues that may need veterinary intervention. And, foals born after an exceptionally extended gestation will sometimes appear premature, as well, having apparently undergone a stalling of fetal maturation inutero.

So, while you should use the 340 date as a guide, it is not an absolute! We recommend vaccinating your mare for her spring innoculations at about day 310. And, if she is caslicked, that should be removed around that time, as well. By doing so at that time, you can insure that your mare is up on her antibody levels that she'll be passing along to her foal, as well as avoid the possible risk of her foaling through a caslick (that should NEVER be allowed to happen!). But, be aware that if your mare goes longer than 340 days, she isn't late for another month <grin>.

Additionally and as an added caution, inducing a mare without some very specific protocols and caveats being in place, will often result in a premature and/or dead foal being born. It is strongly recommended to NOT induce a mare unless there are very specific reasons for doing so.

Just thought I'd provide some interesting information for those of you expecting foals this spring

Kathy St.Martin
Equine Reproduction Short Courses
Equine Reproduction
Only 1 Day Left of our Holiday Enrollment Special!

[Mare]

You are all so right. I know my vet wont induce. When their done cooking she will have it. Iam alot better than I use to be about waiting. I have never missed one being born. And dont plan to. But I know with each mare how they act, signs ect.. Now this year I have a maiden mare so I will have to set my clock again and get to know how she works. I always say Iam gonna get one of those video cams but I think I would rather go look in person. I wish you all the Best and cant wait to see all the baby pics. Happy New Year to all!

[Lindsayanne]

Thank you for that reminder Kathy.

May I ask a question of you that's just a bit off topic? I'd PM you but I'm sure this will be helpful to someone else.

I just moved to this property and it's about 70% tall fescue. I'm working on getting rid of it but I want to do it without chemicals so it's going to take a few seasons. I was planning on putting my mares up on a drylot as their dates get closer (bred for late summer foals- 7/29 and 9/9) but then my feed store manager was telling me about a product called Equidone, that supposedly counteracts the toxins on fescue and allows you to keep mares out on it. She said she'd used it a few times with success, but do you know anything about the safety or effectiveness of it?

[tightpaycheck]

Ohhh, that would be good for me too. My guys are going in 3 to 4 months, and my grass is fescue too. I put them all in the field with hardly any grass, and I'm hoping they will be ok. They need to eat the seeds to have trouble don't they?

[Little Red Dun]

Originally Posted by tightpaycheck

Ohhh, that would be good for me too. My guys are going in 3 to 4 months, and my grass is fescue too. I put them all in the field with hardly any grass, and I'm hoping they will be ok. They need to eat the seeds to have trouble don't they?

Myself as well just for future reference. I'm in Florida and from what I understand fescue is very common and can be a big problem down here.

[Lindsayanne]

<--- bad thread steeler! bad!!

[prettyqtrs]

Good post.
I too have a question for you....we have a mare that her foals keep getting larger and larger when we breed her. And the stallions we are breeding her to are smaller. She is 15.2 hands and the first stallion she was bred to was 15.2 hands- she had an easy delivery. Next she was bred to a 14.3 hand stallion, she had a rough delivery with this one. And finally, she was bred toa 14.1 hand stallion and she had a horrible delivery. We had to help out and pull the colt, you could tell she was starting to give up, and the colt was massive! The first foal was born around the 340 day mark, the second foal we are unsure of- she was bred twice (two heat cycles in a
row---so she either went a tad bit before the 340 day mark, or a tad bit over the 340 day mark. And with this foal we was over 350 days. She is
a fabulous mare, broke to ride, and produces awesome foals. But we cannot see breeding her again and risking her life (and the foal's life) just to try and get a foal out of her.
Any thoughts?

[Equine Repro]

Originally Posted by Lindsayanne

Thank you for that reminder Kathy.

May I ask a question of you that's just a bit off topic? I'd PM you but I'm sure this will be helpful to someone else.

I just moved to this property and it's about 70% tall fescue. I'm working on getting rid of it but I want to do it without chemicals so it's going to take a few seasons.

Don't bother. Fescue is so pervasive and unless you can get all of your neighbors and their neighbors and THEIR neighbors to address it, it will be back in a few years anyway. And, Fescue is a GREAT pasture grass. The endophytes are actually the problem, so the best solution is to just pull your mares in about 60 days prior to foaling.

I was planning on putting my mares up on a drylot as their dates get closer (bred for late summer foals- 7/29 and 9/9) but then my feed store manager was telling me about a product called Equidone, that supposedly counteracts the toxins on fescue and allows you to keep mares out on it. She said she'd used it a few times with success, but do you know anything about the safety or effectiveness of it?

Domperidone was developed by Clemson University (we hold one of our Equine Reproduction Short Courses there <smile>). It's effective and works very, very well. However, there "are" some drawbacks to it. First being that it "is" expensive. Also, foals that are born to mares that are on it have a higher incidence of failure of passive transfer. The Domeperidone doesn't really counteract the endophytes, it kind of dones an end run around one of the problems associated with it - it stimulates milk production. So, quite frankly, you are better off continuing to drylot your mare and feed her a hay that is endophyte free (alfalfa or bermuda both work well).

And, for the record, anyone here that believes their state is Fescue/endophyte free, think again. We put up a map of the US where fescue is confirmed and there are two states that it is "unconfirmed" in. However, I suspect that's just because no one has really gone out there and looked for it. It's an excellent, hardy grass that does well in drought conditions. So, it definitely serves a purpose!

Hope that helps!

Kathy St.Martin
Equine Reproduction Short Courses
Equine Reproduction
1 Day left of our Holiday Enrollment Special!

[Equine Repro]

Originally Posted by prettyqtrs

Good post.
.we have a mare that her foals keep getting larger and larger when we breed her. And the stallions we are breeding her to are smaller. She is 15.2 hands and the first stallion she was bred to was 15.2 hands- she had an easy delivery. Next she was bred to a 14.3 hand stallion, she had a rough delivery with this one. And finally, she was bred toa 14.1 hand stallion and she had a horrible delivery. We had to help out and pull the colt, you could tell she was starting to give up, and the colt was massive! The first foal was born around the 340 day mark, the second foal we are unsure of- she was bred twice (two heat cycles in a
row---so she either went a tad bit before the 340 day mark, or a tad bit over the 340 day mark. And with this foal we was over 350 days. She is
a fabulous mare, broke to ride, and produces awesome foals. But we cannot see breeding her again and risking her life (and the foal's life) just to try and get a foal out of her.
Any thoughts?

Well, FWIW, Mother Nature dictates that the equine uterus determines the size of the foal. With that said, we find that if you breed to stallions that are broader through the chest than average, there is a higher chance of the foal being larger through that area and may have a more difficult time come delivery day. It is unusual for a foal to be so large that the mare can't deliver it. In all the years I've foaled out mares and all of the foalings I've attended (pushing 700 now), I've had two foals that were overly large. Both foals were born with a bit of assistance and no adverse problems. But, we also made absolutely sure that any subsequent foalings, we were in attendance.

Hope that helps!

Kathy ST.Martin
Equine Reproduction Short Courses
Equine Reproduction
Only 1 day left of our Holiday Enrollment Special!