I'm running a hot wire at 4 inches a foot and a half and at four feet around my goats, ducks, guineas, chickens, horses and a pig. Part of it is to keep them in, but I also want to keep out coyotes and raccoons. Before putting in the fence, I was loosing birds to coyotes and raccoons all the time. I would try to trap them, but only caught raccoons. I've killed more of them then I can count. Dozens and dozens of them. But the ones killing my guineas up in the tree never stopped at my traps, they went straight to the tree and killed a live bird. Coyotes would go for my ducks.
After putting up the hot wire, I can see where their tracks went up to the fence and then turned away. Some would walk the fence a little bit, but they always turned away. It's been almost a year and so far, it's worked great. It is more maintenance, and a lot of inspecting and spraying round up to keep grass from touching the bottom wire.
I have two little goats. They follow the horses around and are out in the pasture, or in the barn, wherever the horses are. They would be easy pray for coyotes, but so far, the fence is keeping them out.
I've lost every cat I've ever had to coyotes. Sooner or later they cross the fence and then disappear. I see coyote tracks and figure that's what happened to my cat.
Having said all that about electric fences, I hate them. They are a HUGE amount of work to keep clean and free of debris. Grass Hoppers love to die on them and short out the line. Wild hogs will hit the fence and then keep going forward. I've had my fence tore apart and busted up by hogs three times in the last year. It's easy to fix, but you have to be on top of it all the time. Round up takes forever and has to be done 4 times a year. If you wait too long, then you have to weed eat everything under the bottom wire to keep it clean. Grass that is wet, from rain, dew or just green will ground out your fence. My charger is a pulse type charger, so it makes a loud popping noise when it's grounding out. This is what we listen for when going on walks.
On Facebook, there are some groups of guys who raise goats and different types of exotic animals. Coyotes are the biggest battle. One coyote can kill a dozen babies in a night and not eat any of them. I've hear of as many as 40 babies being killed by coyotes. Figure that some of these animals are worth a couple grand each, and some are worth a lot more then that, and you can see how serious that can affect an operation!!!
Some have said that snares are the only way to kill them. They will cut a piece out of their fence to trick the coyote to come through there and catch it in the snare. Others have said that you will never kill enough of them to make a difference, so you have to put more effort into fencing to keep them out. The most common way to fence them out is to roll a lenght of fencing on the ground so it's flat, then put your fence up on the inside part of the rolled out fence on the ground. Most use 32 inch tall fencing for the ground part, which means your standing fence needs to be 32 inches inside your property line. I hate the idea of losing that much land, but haven't been able to find another way that is better. Then you connect both fences together. Staple down the flat fence into the ground and hog tie them together.
When the coyote goes to dig under the fence, it hits the fence that is laid flat on the ground. It will never go so far back as to dig under that fence, and will be unable to get through the wire on the ground so it can tunnel under the standing fence.
Here is a picture that shows what I'm saying.