Hay PHINS,
Nupro Gold ... My wife found this product years ago to give to our Lab Groucho. When she got older she started having skin allergys and hot spots. Nupro gold not only worked for her we gave it to Muggs our Neapolitan Mastiff all her life too and now give it to Gracie and Mr. Biggy Fry. Big ( the bug dog ) has a small hot spot on his neck caused by the caller and dog tags that we recently replaced and he too has allergies which require a Benadryl every once in a while but that's it and he almost all black and shines. Gracie has no skin problems at this time, and she too shines. Both have coats which they always get comments on when we take them on road trips to Petsmart or Petco.
I hope this helps ...
Mark