You really should not try to make a diet up by yourself. This illness is one that requires a totally balanced and correct diet. You don't give more protein because they are losing it...that is not the answer.
I strongly suggest that, if you plan to homecook, you do a consult with a vet nutritionist. You can find one at:
American College of Veterinary Nutrition
OR, give your pup dog food approved for this illness.
Good luck!