In my opinion you're doing more damage to her, psychologically, by tieing her - and you are correct that it is cruel. If you can not bring her inside, and again it is my opion that you should, then please build her a kennel run so she is in no danger of strangulation, damage to her throat from throwing herself against the end of the tie off.
Also, please consider giving her another "job," herding dogs are quite adept at multi-tasking. Teach her to cart or drag a sleigh, if that isn't an option talk to another farmer who doesn't winter a herd over and see if that person needs an extra 4 feet. Lend them your girl so she keeps busy - of course this would only be to someone you know and trust well. Or try: Mushing, Pulling, Skijoring, Rally Obedience, Agility, OB classes if your local breed club(s) provide..anything to keep her mind busy.
A strong enough instinct is not going to be controlled by a shock fence. From the sound of it she'll go right through to get to the herd.
40+ years in the dog fancy; SV German Shepherd Dogs & wire coated Dachshunds
· 1 decade ago