As you know, I am a schutzhund nut, so I tend to be very demanding. Since I generally have 3-5 intact males in the house at any given time, I have rules that everyone must follow--even the people. No people allowed while i am feeding everyone. New dogs/puppies get fed in their crate for most of their first year. At meal time I call all the dogs to me and put them on sit-stay in a line while I measure out the feed (at this point the puppy is in the crate). Then I feed, starting with the most senior first, by placing a bowl in front of each dog. Everybody is STILL on sit-stay until I give the command, "Okay, it's yours." Of course the puppy in the crate is fed last, while the others are eating. Dogs learn from each other, so the puppies always seem to catch on very quickly that I want a sit-stay out of them before I will put the bowl down. If not, I work with them until they do get it. Then I close the crate door. (All of my crates are wire, BTW). Each dog also knows that when he is finished eating, he is to sit or lay next to his bowl. Nobody leaves until I pick up each bowl. Then I say, "Okay, you're done." And everybody runs for the door.
This way there is no stealing, no growling, no arguments, and each individual eats exactly whatever mix I intend specifically for them. This, of course, means that I stay right there with them all through dinner. And part of the reason I continue to feed the puppy in the crate even after he has learned the routine, is because puppies get fed 3 times a day, while the adults only get fed once. Leaving food or bones lying around is an invitation to a dog fight as far as I am concerned. Every dog has his own crate and bones belong in the crate at all times. My corrections are verbal. If I really have to get my point across, I take a handfull of ruff on either side of the dog's face and look straight into their eyes, and say, "No, that is NOT acceptable."
Plus I table-proof each dog. Which is to say that I teach them that stealing from the table or counter is unacceptable behavior. I start with a bit of cooked steak. I lay it on the table beside me and pretend to ignore it. The puppy smells that good smell and is there in a flash. but every time the nose goes anywhere NEAR that table, he is told, "No, you may not have it." Sometimes he'll take it anyhow. I pry open the mouth and place the food back on the table so he gets the message loud and clear. Once he is good with that, I start moving the steak around to counters, the corner of the couch, etc. until he is absolutely trustworthy about not touching food unless I tell him, "Okay, it's yours." I vary the food too, steak, cheese, cookies, chips. My dogs do not steal.
We don't have dog fights and I really feel it is because each one knows exactly what behavior is acceptable and what is not. My rules never change and I have disciplined myself to follow-through just as firmly as I have disciplined the dogs. GSDs live to please. It's foolish not to take advantage of that. Makes for a very happy relationship!
Hope some of this is helpful.
Rusty