I second the use of
PetDiets - VNC putting pets' health first!. She has very excellent information. She's one of the only people who can say she isn't selling any product. She just gives sound medical advice about canine nutrition based on real science. Beware the online self-styled nutrition gurus and their "opinions" -- look closely, they are almost always peddling their wares and looking to sell unnecessary products with big claims and no science. Good luck!