Thanks all! They are close to 1 year old.
I really think that it's too young.
Trust me, I've several females between one and 4 years, I will never breed them before 1 year and a half or two years, when I see the different size with my breedings female, I've no doubt with this !;-)
You can breed her this year, but it can be dangerous for your female and she will never produce like a two or 3 years old female