It's an old wives' tale, that business about old dogs can't learn new tricks. I'm not sure where it started, but I'd like to meet her--the old wife, I mean. I'd introduce her to Xena, the nearly 90 year old retriever who only recently was taught to Leave It before eating her meals. Having been the first of my pack of 3, teaching her the manners which would prevent food aggression was hardly on my mind. I was learning to handle crates and potty runs and that's about all I could handle at the time.
With 3 pups in our home now, I have taught the two youngsters to Leave It until I give permission to eat. Sometimes this results in drooling and puddles on the floor. But the good news is that it sends one message loud and clear: "The food belongs to the pack leader" and that's that. All 3 dogs now know this routine, even Xena, who learned the drill less than a year ago. She surprised me by picking it up very quickly. I was totally prepared for the "old dog" attitude and ready to test my training skills.
If you decide to add another dog to your pack, teaching this skill can clearly mean the difference between food fights and respect for one another's chow. It also helps to establish your own ownership of your food. I'll admit to having lost a pizza and a 12" sub to Xena during her puppy hood. We found 1 slice of that pizza hidden under my husband's pillow for safekeeping. Xena always was one to hide her goodies until she was ready for them. Usually that meant burying them, but when you're stuck inside, a pillow will have to do, I suppose. Good thing she has some manners now. I didn't enjoy washing the pizza stain out of those sheets.
I'm proud of you Xena. I hope at 90 I'm still learning new tricks. ; )