“I own a dog. Although, generally, the dog is friendly, it is very large and powerful and I am concerned if he should ever run into another dog or person that antagonized him. Do I need to do anything to protect myself from liability?”
As long as your dog has shown no signs of aggression toward humans or animals, you would not be liable for any incident that may occur. Dogs are considered domestic animals and short of prior bites or other outward signs of aggression, owners of domestic animals are not liable for the acts of their pets unless the owner knew or should have known of demonstrated vicious propensities of their pet.
But if you had a pet rattlesnake, that rattlesnake is considered a wild animal and the owner of the pet rattlesnake would be liable for any attacks or bites. But remember, if the snake attacks another animal, the snake owner would be liable for vet bills up to the amount of the value of the animal itself. If the snake attacks a human, the snake owner would be liable for medical bills of the snake’s victim as well as pain and suffering of the victim.
If you have homeowner’s or renter’s insurance, you should notify them about your pets so in the event an incident occurs with the pet, the homeowner’s or renter’s insurance would cover you for any damages.