Great info, ppl think "oh, free baby horse!" But no, it costs money and time to raise a colt. and if you read about how many homeless horses there are, you need to reconsider breeding. There are many good quality horses out there that nobody can take care of anymore, and you also know exactly what you are getting if you rescue or buy a horse instead of breeding for something that you want.
Please really think about bringing more babies into this world right now, just go to any rescue group, like this one.... https://www.facebook.com/Omegahorserescue Kelly Smith works with the kill buyers trying to save as many as possible with help of other people and groups.
I have a better idea. Go to an auction (they are all over the country) and pull a weaning out of the slaughter pipeline. Yes, even babies ship to slaughter, as well as pregnant mares. Instead of adding to the problem by breeding your mare, go save a life!