Dog sucks on rocks

Question
My friend has rescued a young (about two years old) female Bull Mastiff, from a local no-kill shelter, who has suffered from abuse and neglect.  She is responding wonderfully to the love and care and medical treatment she is getting.  A serious problem remains in that she obsessively finds or digs up rocks, and chews on them and places them on her paw and sucks on them, almost like a pacifier.  She swallowed one on Monday, and is now recovering from surgery after all the usual methods to have her pass it failed.  How can we break her of this rock obsession?

Answer
Coprohagia (the propensity to eat objects other than food) is a little understood emotional disorder. It appears this dog may be suffering from overall anxiety (resulting from past abuse) and may benefit from anxiety reducing medication.  Congratulations to your friend for being a loving person and giving this dog a wonderful new home.  The next step is to discuss medication (short term) to assist this dog during her recovery (which could take months.)  It would also be wise to keep this dog under constant restraint (long extending leash or training leash) so that she cannot reproduce behavior that might result in her further injury or death.  Positive reinforcement training is a wonderful tool; it assists trust between owner and dog, increases problem solving behaviors in the dog, increases cognition and builds the dog's confidence levels.  Your friend should learn about this method and slowly introduce it.  The dog should make a complete behavioral recovery in the next six months.  If her appetite for rocks appears not to diminish, then you are dealing with persistent response that the dog has acquired as a method of self calming.  Continuously making it impossible for the dog to repeat this behavior over a long period of time (a year or more) should extinguish it.