I think I know what's going on here---but first- my explanation may not be for the squeamish!

Cattle can be easily "led" by a hand holding hay. Young cattle are led by letting them suckle on your hand.
A barn or cattle pen will usually have some sort of locking "gate" that is used to hold the cows' head in place. Most often, it is built into the feed trough. Whenever it is desired to immobolize the cow, the cow is coaxed into placing its' head in the gate, and the gate is then closed. Now the cow can't move very much, and the vet can treat her, the rancher can give it shots, the cow can be artificially inseminated, whatever.

I am guessing that someone has been using the power pole as an improvised "gate." I suspect also that, when the PoCo happened upon the scene, the rancher feigned ignorance. As soon as Bessie calms down, there should be no problem guiding her head up and out.