Most
of the foods rated in the 6* category have high levels of protein. The
caution attached to these foods is an acknowledgement that some
veterinary research suggests that feeding high protein dry foods to
puppies may contribute to the development or exacerbation of
musculoskeletal disorders (as excess calcium and overall calories are
believed to). Equally there is veterinary research that suggests that
high protein is not
a factor (and we note that it does not appear to
be a problem for puppies fed high protein natural raw diets). Until
such time as the issue is resolved one way or the other, we continue to
acknowledge that the issue may exist. We do, of course, welcome the
provision of research on this topic.