The Stallion Affect

[Joanne]

Have any of you that have been breeding horses for many years thought about if a stallion has any affect on the mare's gestational length??

You would have to have bred multiple stallions to several mares to be able to really answer this.

I am just curious if any of you have ever seen a trend with your stallions......

 

[ontherisefarm]

Joanne I have always been told that the foal determines length .As it is the foal that secretes the hormones that bring on labor. It is in my breeding managment and foal development book.

 

[coopermini]

Coming from a cattle back ground in beef and dairy cattle the sire can influence the length of gestation. Some sires are currently labeled in AI catalogs as having shorter or longer than normal gestations. I don't see why that is not possible with horses. Might be tougher to identify due to the limited number of foals born each year as well as the general variation in gestation lenght in minis to begin with.

Mark

 

[joyenes]

I have bred with the same stallion for 7 years having from 2 to 8 foals a season. The gestation period has been between 300 days to 366 days. So I couldn't say that he determines a short or longer gestation as the mares are all over the board

I have noticed however that my 300 day mare always foaled at that time, my 335 day mare is always within a day or two of that time. I have a 345 ish day mare that on her first pregnacy went 366 and now has settled to the mid 340's. Currently I'm waiting on a maiden that is at 360 days

 

[Joanne]

This is my 17th year breeding miniature horses. I wish I could say my mares had a trend like yours joyenes. Mine are all over the map. But I am breeding the mares to different stallions over their breeding years span.

Perhaps that is why I am looking at other patterns such as the stallion possibility.

Mark (coopermini), your information on cattle is insightful. At least now I know that it is a possibility. Also, very cool that the cattle industry is so on top of that kind of scientific information. It takes a lot of people gathering data to make that kind of scientific prediction.

I have a mare that is "due" now that has been bred to the same stallion on all her previous three breedings. In 2008 I bred her to a different stallion and this pregnancy is going on much longer than her previous gestations. Which is why I started thinking about all this.

 

[BlueStar]

I honestly think this is a fact. I have a mare that has been bred to 5 different stallions. A couple of the stallion owners said the foals by this stallion are routinely a shorter gestation....that also held true with when bred to my mare. Our stallion that she has been bred to 4-5 times will routinely "cook" longer. This also holds true when we have bred our stallion to other mares. His foals just seem to need a little longer to mature in utero. I have also noticed that gestation time on most of the colts take longer than the fillies. Just my observation though.

 

[mizbeth]

Mine are all over the map too, so to speak. In my opinion it has nothing to do with the stallion.

It is all up to God!

 

[faithfarm]

I have been tracking the gestations on my mares for several years and really believe that the stallion has some effect on the gestation period. By the way Mizbeth, Mari has gone 327, 328, but went 318 this year. Most of my mares were early this year for some reason.

Rick

 

[crponies]

I know I read an article a while ago about some research being done that found the stallion did affect the gestation length.

 

[Joanne]

Jayne if you find the article, can you please post the link for us???

Thanks.