Switzerland deploys roughly 300 livestock guardian dogs — mostly Maremmano-Abruzzese and Pyrenean Mountain Dog breeds — on alpine pastures to protect sheep and goat herds from wolves and, occasionally, other predators. They live with the herd full-time and are trained to treat any unfamiliar presence, including hikers, cautiously.
If you're hiking with your own dog, the official guidance is direct: guardian dogs generally see other dogs as a bigger threat to their herd than they see humans. If your route passes through a marked guardian-dog area, it's genuinely worth considering leaving your dog on this particular hike, or choosing an alternate trail. An interactive map from Switzerland's livestock protection service shows current guardian-dog zones before you set out.
If you do encounter a guarded herd: stay calm, put your own dog on a leash immediately, don't approach the livestock, and take the widest possible detour around the herd rather than walking through it. If a guardian dog approaches barking, stop, avoid direct eye contact, don't turn and run, and wait calmly at a distance until it settles — then continue slowly. In over 20 years of guardian dogs being used in Switzerland, no case of serious injury to a hiker has been documented.