My dog Wode was put on Science Diet Adult Light for Large Breed because he needed to lose weight since we just repaired his torn ACL. We feed both Rotties the same food. Jenny has always been slim (and Wode has always been fat because he finishes her food). We put them both on the same food but we give Jenny a little bit more since she does not need to lose weight. (We give him 4 1/2 cups/day and give her 7 cups/day). She is now very skinny to the point where you can somewhat see her ribs, vertebrae, and pelvic bone?. Is this the food or should she see a vet for something serious?