Kita's right. Resource guarding is what most dogs do naturally anyway. They become attached to various objects or toys, which are "theirs", so taking whatever away, is as bad for your pup as if you were taking a child's toy away. We have Staffies, and another thing to watch out for is if they swallow stones. Rather than tip them up, they'll swallow them to "keep them", so you have to tempt them to drop the objects by offering a favourite titbit, for instance. A high percentage of dogs needing operations for blockages, are Staffies. One of ours needed 3 ops in 4 months, costing almost �2000 a time, so it's well worth training your pup to "drop" in favour of something even better!