Worried about move

[cúréaltach]

Hi folks, This post is the reason I joined this forum and any advice will be greatly appreciated thanks.
I'm living on the south coast of Ireland with a B-Collie/GSD X,2 years young, female, neutered and an Intact 2-3 year old Austrailian Shepherd male. The collie X I've had since she was 7 wks old and fully obedience trained her using positive reinforcement and the so called "dog whispering" techniques. The A-Shepherd is a stray I picked up about 5 months ago, I'm still dealing with issues mostly aggression with other males (I know the "big" fix for that and he'll be suffering that soon, mostly 'cause I dont want to bring any puppies into the world).
Now my question....I am moving in 2 wks time to a new house surrounded by cow fields and any cattle chasing WILL result in a dog being shot. The collie X is no prob but I'm unsure of the A-shep, the technique I'm thinking of using to keep the dogs within my boundries is ..... sitting outside and using an air horn (like in football matches) or other loud "something" to make a negative association with crossing the boundry. I will NOT use those shock or spray collars with the underground wires. I always have the dogs under controll and dont let them wander but it only takes one slip up and well..........gulp!
Any advice greatly appreciated. Thanks!!!! Happy walking....