My 12 yr old Bulgarian Shepherd has started waking me up in the night to go out and spends half an hour or so frantically eating grass and weeds before doing a small badly formed poo and coming back in. She is eating normally, basicly 50pc green tripe with chicken carcass or lamb ribs/neck etc and treats I make from dehydrated lites. Since she is a rescue dog who spent her first few years on the streets scavenging, I am puzzled at this new behaviour and not a little upset as I need my sleep. Vet examined her and merely suggested no more bones!!! Anyone experienced anything similar?