I am not a breeder or an expert. I am sorry I don't have any advice, but I can tell you my story with a skinny little guy. I got Oscar from a pet store and he was grossly underweight, you could see his bones sticking out of his tiny body. I was never told if he was the runt or anything, but I assumed it since he was smaller than the rest, including his little sister. When we came home I would cry day and night hoping he would eat, and he wouldn't I would try feeding him by hand and still nothing. I didn't know what to do. I would look at this little skeletor (I used to call him) and just bawl because I didn't think he would make it. I know a lot of people end up having to feed them through syringes and such. Luckily Oscar started eating little by little. By the time he was 1 he only weighed something like 40 pounds. Everyone would wonder why he was so skinny. Eventually he ate more and more as the days went on and now at 3 years of age he's 65 pounds. It took him a long time to fill out. I'll tell you one thing though, it has not affected his ability to learn, love and play one bit. He's as smart as the biggest dog in the park, and can play with the biggest of dogs. He's not too tall but everyone tells me he's a perfect size, some even tell me he's small for a boxer ( some don't believe he's full grown yet !)which could be true, but I don't care because he is mine and I love him no matter what! Oscars weight and malnutritions and all the sicknesses he had as a puppy never affected his developmental skills. I wish you the best of luck with your pup and know that there are plenty of people here to help. I am sorry I couldn't be better help to you.
