Ordinarily, you can use training poppers for a 12 Gauge....nothing more than primed empty hulls with just the primer bang.....first thing to do is to let the dog be chowing down on some food while he's hungry and eating and then start easing into to the poppers moving closer from farther...
I was driving down W. Church Street in Jasper on a 45 MPH stretch and suddenly a doe and three fawns following her darted across the road in front of me. I am so glad no one was behind me because I had to brake real hard not to hit any of them.
You got a pasture, maybe some cows, goats or whatever livestock, get a Donkey....they're kicking fools and will protect a whole flock.....I've seen it...
Good luck with that. I live in Pickens county. Coyote got me cat a few years ago, they've gotten some dogs here, too. I drive by a farm where the guy raises beef cattle and he has to keep a donkey out with them just to keep the Coyotes away....