shouldn’t think that having your dog eat raw bird will make him better at sniffing out live ones. What would is having him associate sniffing them out with getting a reward that would be of high value to him. I’d think a well bred bird dog would have the instinctual drive to hunt out birds, it would just have to be trained into him what sort of bird he should sniff out.
But as I said, I don’t know much about hunting or training dogs specifically for that, just based on my general knowledge of dog training.