Garlic contains compounds that can cause anemia if ingested in extra large amounts. Anything that is in excess is not good for the body, whether it is a human or an animal
Small amounts of garlic per body weight is good for the dogs. It actually helps with fleas, mosquitoes, and ticks. It’s supposedly gives the bugs a nasty taste to deter them.
Garlic also builds the immune system. It detoxifies the liver, helps fight infections, and is good for cardiovascular health.