The only female that I bred this year was a second year female. That being said, I feel like I was reading her behavior and she was showing me all the signs that she was ready to go. She weighed 1600 grams the first time I bred her, and was quite stocky for her length. She crammed in the food and kept eating up until two weeks before she ovulated. Just before she layed her eggs she weighed in at 1900 grams.
I think I read the signs right, because she produced 7 perfect eggs with no issue in mid July, and has already bounced back to around 1500 grams.
I also had another second year female I considered breeding. She was not giving me any of the same signs though, and she tried to go off food early in the season. She has hovered around 1300 grams for nearly a year now, and I did not ever really consider breeding her after observing her behavior. I think it can be done, but each animal needs to be considered as an individual, and that the general rule for a LARGE MAJORITY of females should be wait until the third year.