I hesitate to post this since you never know who will read it and what they will take away but I recently read an article (in The Horse I think) that said studies(or
a study) have shown that the mares who are bred when they are in the best condition are most likely to have a colt. Something about nature seeing a need for more fillies to be born when times are harder for the horses (in the wild of course) since one colt can breed many mares but each filly only has one shot per year. So having more mares when the going gets tough makes it more likely some will be available to reproduce. Its been a little while but I think that was the main point of the article. Sooo.... those of you who are getting lots of colts can take it as mother natures way of saying you are taking excellent care of your horses