I use pigeons for pointer training and they work fine. All game birds smell a little different, but they all smell like a bird.
I would never let the dog catch a live bird or let him chew on a wing or foot or feather. If the dog is to be used for locating birds as you would with a pointer it must never be allowed to get within a couple of feet of a live bird. I would teach the dog " whoa " before even doing anything with a live bird. When the dog can be whoa'ed consistantly then let him see the live bird.

The behavior you describe sounds ok for a retriever. They are bred mainly for sight retrieval. The dogs will work for locating birds but it's not the dog's true calling.

Good Luck!