Augmented Reality and Getting Rid of Fences

Or How Technology Could Destroy the Cowboy

This idea is several years old, it lay dormant, until the joy of Pokemon Go brought it back.  Currently farmers who have live stock will often need to enclose their property with many miles of barbed wire or electric fencing to control where their animals are at a given time.  In an era with ever cheaper augmented reality technologies it could soon be possible to create smart goggles for animals.  Ok, I bet you're thinking, this is crazy, but bear with me.  If I have a large herd of cattle, I can equip them all with special goggles, that would allow ranchers to tell the cow should be at any time, all without herding the animal.
The goggles would provide a visual overlay onto a given animal's field of view, and at any time the cow, sheep, goat, etc... tries going into an area where a farmer doesn't want them, the goggles would provide a visual cue to make them want to go some other direction.  If the visual cue isn't enough, a system similar to a dog's shock collar would be activated to provide negative reinforcement.  The technology could go even further, scientists are developing bio-medical sensors to look for health indicators, the goggle system could actively report the health and location of all of a farmer's cattle, as time goes on the system would even include diet control, so when a cow goes up to its feed pen, the machine ensures that any nutritional gaps are filled.  Now the cost of this technology would need to be low, but in theory secondary cost savings could raise what that acceptable price would be.  First the reduced need for fence maintenance, probably a good thing, theft prevention, now the cows will only look for people that are authorized to do anything with the animal, if something isn't authorized, well it will look scary and the cow would go the other direction.  Harder to quantify now, but my gut says it might be useful, reducing ecological where wear and tear, as farmers no longer need to directly watch their herd, the computer can keep them grazing over a much more dynamic landscape, reducing the negative impacts of too many cows in too close an area over a given time.

(this article is now making me want to think more about smart farming, I'll try to keep coming up with additional ideas, and make a mega post later on)

As per usual, please feel free to comment share, feedback is always appreciated.

Edit July 14 2016
Another thought occurs, if this technology is affordable enough to equip the world's cattle with, we could start adding it to endangered mega-fauna (read elephants, rhinos, pandas)  There are stories of communities in Sub-Sahara Africa using lines of bee colonies to dissuade local elephants from entering into human farm land.  With augmented reality tech for wildlife, such needs could be reduced.  Secondary benefits could include the ability to monitor overall herd health, and serve as a way to provide evidence against poachers.  Another potential benefit for those in places like Alaska, young bears who haven't quite learned that entering human controlled spaces could be more actively convinced to not return to places with people, and when they see people in their territory, the human could look scarier.  (crap I should have been lazy and made this into a brand new post)