Drying meat is a tricky thing. I am no expert on it, but I have dried some meat for human consumption, but it has always involved salty marinades (aka jerky), which won't work for poultry because of the high salt content.
You might find it easier to grind the meat and freeze it. You could cook it first before freezing, but I don't know if that would matter much. To feed, you would want to measure an amount of thawed ground meat (for protein and fat) to an appropriate measured amount of grains, vitamins and minerals. It would be a meal type of feeding program, not something you could mix up and store in an container in your garage, of course.
I use a commercial fish meal made by Fertrell. They use a rosemary extract called Naturox to preserve the fish meal. I am not sure if you can buy this retail or what the application entails. Could be something to look into. There are traditional preservatives like sodium nitrate/nitrite, etc, but I don't know much about them or if they are safe for poultry use.