The rock salt thing is a rural myth. Everyone knows someone who knows someone who has done it (shotguns loaded with rock salt were also used to shoot kids stealing melons and/or gasoline from the farm tanks), but nobody has actually used it themselves. I have a shotshell reloader and I'd never shoot it through any gun I own and as others have said, it would make for an extremely poor and ineffective load if you did. Then there is the practical problem of who is going to sit around with a gun to be ready 24/7, for days or weeks on end to get a chance to shoot one?
If you have stray dogs, this is your solution:
https://www.backyardchickens.com/threads/dogs-and-electric-fences.1210854/
Done right an E-Fence is almost 100% effective, always on guard and you never have to shoot anything.
If you have stray dogs, this is your solution:
https://www.backyardchickens.com/threads/dogs-and-electric-fences.1210854/
Done right an E-Fence is almost 100% effective, always on guard and you never have to shoot anything.