Most Dog habits begin from puppy stage. It was a behavior left unattended and later in the dogs life, It becomes a problem, both for the dog and the owner.
Resource guarding is a very dangerous behavior. For example, An adult dog was brought to my house and i fed the dog. while the dog was eating, i was going to the door and immediately my leg got close to her food, she bit me on the leg. Now this is how dangerous the behavior can be.
A dog with this behavior has assumed the position of a pack leader. He will guard whatever he consider HIS.
Things like:
- Food
- Toys
- Personal space or sleeping space
- Leash
- Food or water bowl
- Puppy or other dogs.

Dealing With Resource Guarding
Resource guarding can be well contained if noticed from puppy stage. However, It can be managed at adult stage. here are some steps to contain this behavior.
Training: The most important step after owning a dog is training. Training gets rid of most dog behaviors and makes them more well-behaved.
Pack-Order: If a dog is preventing you from picking its plates, it has assumed the position of the pack leader. Re-take your position as the leader of the pack.
Saying NO: With a firm NO make him know you aren't joking. pick up the toy and place it where he'll see it but cant touch.(If he doesn't listen, wait till he has left the toy.) keep it there for days. when next you want to offer the toy, make sure he sits before you offer the toy.
Teach the leave-it command: This also helps. follow this few steps
hold a treat your dog likes up and say "leave it". when your dog drops the toy, pick up the toy and give him the treat.
Have you had this problem in the past? how did you deal with it? lets hear your view in the comments box.