breeding for height

Question
We have a lovely, well bred Welsh show pony with a wonderful temperament.
However she is only 12.2hh and will be outgrown by my children soon. If we
were to breed from her (she is 10) how big a stallion could we go to, to try to
get a bigger foal safely,bearing in mind she has not had a foal previously. I am
5ft2 and weigh 115lbs and would love a bigger version of her! Unrealistic of me?

Answer
Hi Mel,

It could be realistic to get a little bit of a bigger version, but I don't think you're going to get much bigger.  I think that considering her size, you're still going to have to breed her to a pony, rather than a horse.  If I were to choose a pony to breed this mare to, I would go with a POA that is close to 14hh if you're wanting to breed her by live cover.

It has been said that a mare will not carry a foal that is too big for her to deliver, the problem arises when it comes to breeding.  But even if you were to choose to breed her by AI, you're not going to get a 15hh horse out of her if you bred her to a 16hh horse.  Her genes are still going to come into play.  The general rule is, that if a mare is bred to a stud that is much bigger than her, you can still expect the foal to only reach a mature height of maybe a couple of inches taller than its dam.  The other problem you could run into if you AI'd her by a much larger stallion, would be that the foal would grow so quickly, it could have problems nursing by not being able to reach the udder comfortably.

It sounds by your size, that you're not a very big person at all.  A 13-13.2hh would probably work well for you.  So, you should look at something around the 14hh range to breed her to.

Now, the fact that she is 10 yrs old and has never been bred, could also pose another problem.  The conception rate in mares over the age of ten years decreases.  I'm not saying it isn't possible, but you could be working at it a bit to get her in foal.  My advice would be that before you even pay out a stud fee, that you have the mare checked to make sure she is reproductively sound.  You want to make sure her ovaries are healthy and ovulating.  You also want to have her uterus checked for any cysts or pyometra.  The common problem in mares that age are the cysts.

Best of luck,
Sandy