While cheese, at least most kinds, is not toxic to dogs, there are some things you need to know to keep your dog out of digestive trouble.
First of all, never feed your dog blue cheese or any other “mouldy” cheese like Stilton or Gorgonzola. The mold in these cheeses produces a mycotoxin that is toxic to dogs
Also never give your dog any cheese that has other ingredients in it, such as chives or onions, or extra salt, which are also toxic to dogs.
Cheeses that are generally safe for dogs include young cheddar, mozzarella, string cheese, low sodium cottage cheese and plain cream cheese. Cheese is high in fat, so you may want to choose a low fat brand. Aged cheeses are generally very high in salt and this can adversely affect your dog, so stay away from these. For dogs with kidney disease, their salt intake must be carefully monitored, so check with your vet to see if any cheese is a safe choice.
Some dogs are lactose intolerant, meaning that their digestive systems cannot handle any dairy products. Test this first with a very small piece of cheese and then observe your dog carefully for the next 24 hours for any sign of digestive upset, including gas, diarrhea. If your dog shows any adverse effects, then avoid cheese altogether.
Cheese should be given only occasionally and only as a treat. If you have any concerns about whether cheese is safe for your canine companion, consult with your veterinarian.