Question Author
Thanks everyone for such a quick response, I am impressed.
SFt42 - my dog was badly beaten as a pup. Her behaviour when she was rescued was diabolical and she was referred to a dog psychologist who managed to sort out all of her problems. She had 3 homes prior to mine where she didn't even last the day! The only habit she now has is to suck her duvet, a bit like a child with a security blanket, but that is not a problem.
Indiesinger - she has been speyed and I don't know if she had puppies before I owned her. She was 18 months old when I got her.
DawnDpt - she is loved and cherished. She was formerly alpha dog but for the last 2 years she has had to kowtow to a larger and younger male dog. He is assertive but not aggressive towards her whereas she has drawn blood from him.
woofgang - She may be stressed, although her life is pretty good, who knows. I am concerned about her physical condition relating to her broken vertebrae though. When her hackles go up there is a flat patch where the nerves are damaged, very weird to see. I watched her yesterday and she always walks anti-clockwise so it may be related to her back. I feel a visit to the vets coming on, luckily my practice charges very little for animals who have been rescued