Is he fixed is?, would be my 1st question. If he's not then about 2 years from what I have read he will fill out. I have a female, she is 16 months old. and we let her run and play all the time so she has musle behind her, But not male looking. Playing and swimming build their tone. If he is fixed the tone is what you will have to work on. You also need to look at what the parents and Granparents looked like. I can give you only my opion here but my Dallas parents are standard(sp) to the breed. So I can look for her to be about the same. The bigger the rottie is not always the better. Bigger rottie's get hip problems. I would say if the vet says he is good weight for his size stay with the vet. And if musle tone is your consren more playing, running and swimming if he likes water, and it's warm out.
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