I have a 4 year old rescue doberman who has recently started eating all the time. He gets fed twice a day and given treats now and then. For the post 1-2weeks he is eating everything he sees. When i take him for a walk he grabs every scrp off the floor and lunges for peoples bags to get the contents. He has never done this before and all his wormers and injections are up to date. Does any one have any idea why he is doing this or how to stop him???

If this is new behaviour, I would take him to the vet for a check-up.