I wouldn't breed a 1 year old Chinese, especially for her first litter. Pregnancy and litter rearing takes a lot out of them and for the health of mum and pups it's better not to breed that old. I prefer 4-6 months for a first litter, though will go up to 7-8 months if needed. Sometimes I have a second litter from a girl, about 3-4 months after her first, but not over the age of 1. If you want to breed Chinese then I would suggest finding a younger girl from good stock