I would say that the word "protein," by itself, needs to be examined ... and replaced with
the highest-quality, most biologically-available protein possible
All proteins are
not created equally as far as their usefulness goes ... some being easy on the dog to process ... others being very difficult to process at all ... which distinction is vital to understand
why there are sometimes problems
For example, if your dog is struggling with a lot of work, isn't being given enough water, and is being fed cheap kibble where "corn gluten" is the source of protein, then he is going to get kidney problems ... 1) because he's dehydrated (which EWO pointed out is the #1 problem), and 2) whatever protein the dog *is* getting, SUCKS!, isn't easily-processed by the dog, which also causes his kidneys to work hard. [This can also be true for those super-high-protein "grain-free" kibbles (like Innova Evo) which also cause dehydration.]
By contrast, if your dog is doing a lot of work, has plenty of water, and is eating a RAW diet of chicken, egg proteins, and even easily-digested protein supplements ... then he should have NO kidney problems at all.
Jack
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