Being moderately insane and just wanting to know if it would work, I got three
milk goats for clearing brush, and put them out to pasture using a radio transmitter type of
fence, with collar. A few facts, first of all, we have very good fences since we used to have sheep, secondly, we have a very secure place for them to sleep, with platforms, milking station, etc. So, the goats really can't go too far, and coyotes, etc can't get to them easily. Also, there is a worker near them all day long.
Saying that, the
fence is working, in fact, the goats were easier to train than dogs in my opinion. One thing with animals in training is never assume they remember to the next day, until you get past about a week. Each day, they have to learn the lesson a little less. We take the collars off every night at milking - which is recommended for these systems so that sores don't develop.
Less painful than a true electric fence, and a heck of a lot cheaper. Granted, I already have really good woven fencing, but it wouldn't stop a determined goat. The goats have decided to leave the
trees alone after we painted the bark with a mix of really hot pepper and
water. We just harvest the ones falling from the tree (yes, peppers are a tree here, about 2 meters tall) put them in a container with water, and if the goats act like a tree bark is tasty, we paint it. End of problem. They can browse on all the leaves they want.
Our three goats are producing a little more than 2 gallons of milk per day, with two milkings. They are pretty young, so we are pleased, besides, I am not really after milk as much as for them to eat vines, brush, etc. - though I do like goat cheese when we make it (and we do consume all the milk)