Be very careful using Garlic (same with Onion/chives etc) with your dogs (cats are much more sensitive), it has a substance in it (thiosulphate) that can destroy red blood cells which can cause anemia, kidney failure and in rare cases death. I have read that in low doses it can be beneficial (as it's stated that the toxicity comes from very large doses), and is probably ok, but having all the info never hurts! Just speak with your vet about dosage beforehand.