Horses don't count as ag here unless you file all the forms and prove you are a business. A friend of ours does that, he trains driving horses and attends shows all over the country and has competed overseas. But for the person with a family "backyard" pleasure horse, no.
If you are in an area that they are popular, then hope it works. Cattle are easier to fence than goats and sheep, but I would still be concerned about fencing if the acreages are smaller...BECAUSE... it usually means a more dense human population. That can get into issues of animals getting loose, causing damage. A good fence that is woven type wire (also called field fence some places) is preferable for any and all perimeter fencing in areas where the typical acreage is 3-10 acre sizes. It is not only to keep the animals home, but to keep the unwanted PEOPLE ; ie: KIDS; out. Any type of electric can also be a problem; heard of someone who's kids got tangled up in some electric and they sued the owner for the emotional TRAUMA the kids suffered....FOR PETE"S SAKE. The landowners won, but the time and trouble ...... Electric netting is a good way to keep things in and do rotational grazing..... but an animal that is scared or mad will go through it. A good tight woven wire fence is more of a physical barrier in those situations. NO FENCE will contain any/everything all the time. But it helps to have the best you can.
Another thing to consider is if you ever do want to change or add different species, like sheep or goats, the fencing is already in place....and you can keep LGD's in a good tight fence.
Don't get me wrong, we have woven wire on some places and anything that we do fencing for that we have at least a 10 year lease on, we put up woven wire. But we have a few places that has 6-8 strands high tensile, some electric some not. Cattle will learn that they can put their heads through it, and then pull back out, it is "springy" for that very reason, so that it can spring back from branches etc falling on it or cattle hitting it, but if not electricfied, they will learn to just go through it. I personally hate it as we have had trouble with coyotes running calves and have had 2 try to jump through in a panic, get their hooves caught and hung up and died before we found them the next day. Many farmers really like it. It is great for rough hilly, rocky terrain where posts may be hard to drive as you can get by with less and more infrequently spaced posts.
We have 3-6 strand barbed wire fences some places, and they do a good job of keeping the cattle in. But most of these places do not have anything like a beautiful green lawn or hayfield right next to them to tempt them to want to get out. You need to consider what will be on the other side of the fence so that whatever you do put up, you will be as sure as possible of keeping in what you are trying to contain.
One other thing, woven wire, properly put up will also keep out most all predators like coyotes and DOGS. It is not cheap....but once up, you are looking at 20-50 years of not having to worry about it unless a tree falls on it or a car runs through it if alongside a road. Run a strand of electrified barbed wire along the top and it will keep out people too. Post your signs and make sure your AGRICULTURAL PROPERTY INSURANCE will cover you. We have learned all these little things over the years.
Some of the "always have been" smaller breeds are also dual purpose. So milk and meat.
I would love to lease a cow for 2 months to get myself OVER this. My goats give me more milk than I need, it's delish, they are smaller than a cow, eat less, I have a cream separator. I need to chill! 
