All four of our dogs get about a tablespoon of yogurt on all of their meals (twice a day). Have been doing this for about a year, and have vet approval for it. The reason we do it is to prevent gas - greyhound gas is deadly! It really, truly works, too - if our dogs miss their yogurt for a couple of days, the gas problem returns in full force. Just make sure that it's plain, low-fat yogurt. Some dogs can have a problem with fruit or other flavorings.