broodmare

Hello again everyone. I have a concern about one of my broodmares. Shirley is a 13yo mare that I purchased in the spring of 2013. She was in foal at time of purchase and foaled a filly for me with great ease that May. She never seemed to get pulled down or loose weight the entire time she was...

What age did you breed your mare for the first time and felt that it was safe? Would you think 3 to foal at 4 would be okay?