Our New Adopted Dog, Peter - A Rescue Dog in Survivor/Scavenger Mode

Question
Peter is about 1-1 1/2 years old neutered and microchipped beautuful blonde and black retriever/hound dog rescued from the Humane Society  of South MississippiGulfport Mississippi by Puppy Angels on Dec 30th then myself and my fiance this past Saturday afternoon (Jan 14th).  He is really gentle by nature by is in what I believe is a scavenger/survivor mode.  We already have a 5 month old lab mix (also neutered) and 1 adult cat and kitten.  Once Peter settles down he is wonderful with us and the pets.  He was obviously starving (you can see his ribs) and is on health wise (Chicken & oatmeal - 1 1/2 cups twice a day).  We must feed the dogs separately and I had to move the cats food to the basement since he will try to eat anything in sight.  He is about 50 lbs and very strong.  We love him already and want him to love our family as much as we are growing to love him.  Please tell me how to handle this without becoming too frustrated (and extremely exhausted).  We live in NH, have 4 acres of land - which when we are outside with the dogs are free to run.  While at work they are in a kennel with an insulated dog house - which was originally built for Buddy.  We wanted Buddy to have a playmate - and introduced them first at the the sponsor kennel for Puppy Angels.  They seemed indifferent at first then started to run together and play together.  We couldn't leave Peter behind after meeting him.  We all wanted so much to bring him home with us and bring him back to good health in a warm and loving home where he will grow to  know that he is loved and is one of our family.  

How do we deal with his incessant need to scavenge for food and get him to realize he will have meals every day and more love than he will ever need.  How do we get him to stop stealing from Buddy (even when he has his own chew sticks).  How long will it take before he is comforted, and knows he is now in a safe, loving and caring environment.  And, any please pass on any other advice that you think important - your prompt response will be greatly appreciated.  

Answer
Unfortunatly,there isn't alot you can do for dogs trying to eat everything in sight,but my one dog is like that,and he has never gone hungry in his life! But if he is always eating and not gaining anything,that would be cause for concern and would have to be taken to the vet,and if you want,you might want to try to talk to a dog trainer and see if there's anything you can do