New Breeding Poll - Fillies vs Colts

[Equine_Reproduction]

We have updated our gestational duration survey which can be found in the article on our website at http://www.equine-reproduction.com/articles/overdue.shtml

Previously, we simply requested gestational durations of live foals in various ranges, then recently someone asked: “is it true that colts are carried longer?” and we answered “oh yes, everyone knows that… errr…” - but do we really? So now we have recreated the survey to allow entry of the gestational durations for either colts or fillies in a different field. Hopefully over the years we will build up another statistically significant number of entries - the former survey had over 4,200 gestational durations logged - and please keep entering your gestational lengths in!!! Those are still shown in the article, but we’ll also reproduce them below for you. It is interesting to note that although the highest range of gestational durations are between 339-350 (27.5%) the second highest range is those mares that foaled with a duration greater than 371 days!! (20.68% - and I do recognize that this is a slewed statistic as it is not a limited number of days such as the other categories are, but it is still important to realize that a significant percentage of mares successfully carry longer than one would expect!).

Please do take the time to enter the gestational duration of your live foals in the applicable category when they arrive - Fillies, Colts and total gestational length! Not only does it help us, but I think it also assists breeders - and in some case perhaps calms mare owners down a bit…

319 Days or fewer: 4.51%
320-326 Days: 7.05%
327-332 Days: 7.55%
333-338 Days: 9.59%
339-344 Days: 14.77%
345-350 Days: 12.73%
351-356 Days: 8.83%
357-362 Days: 5.86%
363-370 Days: 8.43%
371 Days or greater: 20.68%

Total Foalings Reported: 4212

Additionally, we now have a Facebook Group page :D! Come join us especially if you have repro questions! https://www.facebook.com/groups/EquineRepro/

Thanks everyone for helping!

[camohn]

so far (with only 132 entries) it looks pretty even up to 350 days, and colts are less likely to go over that!

[mbm]

i am curious about the original poll. it shows a large percentage of mares going over a year. How can that be? is it because mare owners who are worried about how long their mare is taking to foal searched and found your article?

i am fascinated with the results and keep thinking about it!

[exvet]

Well mbm I did not answer the poll but all I can say is that both of my maidens last year, both ponies of very different breeding, bred to the same stallion carried a year or more. Cosmo carried for 363 days and Maddie carried for 379 :eek: A healthy filly (now yearlings) were born to each. Maddie has been bred back to the same stallion for 2014. It will be interesting to see if she carries over a year again.

[SportArab]

First foal of the year is a filly. Mare last bred on March 31, 2012. Filly born on March 15, 2013.

This is the second filly in a row for this mare. She had three colts previously and the colts did take longer.

What I’ve also noticed is that the mares who are bred earlier in the year take longer than those who are bred later (say in Sept. or Oct)

[Sunnydays]

I too am surprised by the stats showing large #s foaling after >1 year gestation. In the 40 to 50 births here, the longest gestation has been 357 days, with 2 going to 349 days. I have had more than that foaling at less than 320 days (about 6).

I would probably have committed hari-kari long ago if my girls made me wait a year for foaling.

[siegi_b]

Ditto to Sunnydays’ post.

[mbm]

[QUOTE=exvet;6925150]
Well mbm I did not answer the poll but all I can say is that both of my maidens last year, both ponies of very different breeding, bred to the same stallion carried a year or more. .[/QUOTE]

I would of gone nuts!! it will be interesting to see how long they go this year. …

i have, in theory, 1.5 months to go and i would die of suspense if i had to wait til mid/late june!

i have also heard that mares due earlier in the year tend to carry longer…

exvet - when were your mares due ? which month?

[exvet]

They were due in April of last year. They were bred the same weekend and while both went well into May, they were about 2 weeks apart. I was going to breed my Manhattan mare to the same stallion this year but I’m toying with the idea of taking her to someone else (another stallion) and will very possibly be breeding Cosmo back this year to my stallion instead. So I could get a repeat of the twisted sista’s which I would be OK with since I am very happy with what we got the last time. Both are shaping up to be very nice movers with solid engines. This time we’ll see who does what…goes how long…causes me to lose how much sleep :winkgrin::lol: Seriously other than the wait, both foalings went very well. Looking forward to see what you end up with and when

[Spike]

Is the poll open only for foals born in 2013 or can we enter the foals we had from the previous years?

[camohn]

the APHA in it’s ultimate wisdom should read this. One year one of the foals I had that went over 365 was finally born. Sleeplessness aside, the real problem was this: She was bred, checked in foal then turned out with the stallion. Now it is entirely possible she slipped the first pregnancy and got re bred out in the field. However, the breeding report I submitted to the APHA with the breeding dates had the original cover dates on it. They sent my registration paper app back refusing to register her because the breeding dates did not match the foaling dates. You would not believe how much trouble they gave me trying to register the foal!