Though resource guarding may be normal dog behavior, this habit can be dangerous when directed toward humans. Dogs naturally guard any object they view as theirs, including food, toys and bones. If your dog guards his bones, take steps to correct this behavior so you won't get bitten. You can do this with 2 training techniques: desensitization and counter conditioning.
Stand a few feet away from your dog as he chews on a bone. Talk to him in a calm, positive voice. Toss treats from this distance every few seconds, every time your dog chews a bone. When you can get through 10 sessions without your dog behaving aggressively, move to Step 2.
Take one step toward your dog and his bone. Simultaneously toss him a treat and talk to him; immediately move back to your original position. Repeat for 5 to 10 minutes or until your dog loses interest in the bone.
Repeat Step 2, getting closer each session, until you can get within 2 feet of your dog without his showing aggression.
Stand directly next to your dog and his bone. Drop a treat on the floor and leave. Return a few seconds later and repeat. Eventually you should be able to get through at least 10 sessions without your dog guarding his bone or behaving aggressively.
Offer your dog a treat from your hand, several inches away from the bone. Gradually work your hand closer and closer to your dog over several sessions until you can touch the bone consistently without your dog threatening to bite.
Pick the bone up off the floor and replace it with a treat. Drop it immediately and leave. Over several sessions, lift the bone higher and higher, always replacing it with a treat, until you can take it away completely without your dog behaving aggressively.
Repeat steps 1 through 6 with every member of your family, using extreme care with children; back off immediately, to the last phase where your dog succeeded, if he shows any aggression.