What should I do if my puppy was mistreated before?

My husband just brought home a 6 wk. old tea cup chihuahua. It was not taken care of. The little girl is very thin and has patches of fur missing on neck on side. You can actually see its ribs and back spine. It has been eating and drinking. However, if you try and touch its back to pick it up it will growl. Seems scared a lot and does not lick you unless you have something on your finger it likes. Mainly likes to curl up whether on your lap or in her little pen to sleep. Any suggestions? More on What should I do if my puppy was mistreated before?

Posted by Cindy