i wouldnt but i have heard of people breeding as small as 35 grams. idk how the leo is even ovulating at that weight but i guess it can be done. wouldnt reccommend it tho. i prefer to wait till they are 45 grams.
I think that's all relative I think, I've got a petite female, 9 years old and only weighs in at 48 grams. She has side boobs, and a lovely huge tail. She's a BIG healthy girl, and she'd be just fine to breed. (However, we're not breeding her because she's an older lady and we just don't want to jeopardize her lifespan).