Misha should be well able to handle scaring off all but the most persistent predators. For more than that, stronger fences are most likely where you need to go. An LGD for just a few pet goats is kind of overkill. Though I'd do it just because I love my LGDs - lol!
Actually, since you already have equines, a better idea would be a guard donkey. They are easy to find, don't require training, eat what the horses and goats eat (they'll eat stuff on the ground, which goats are very reluctant to do), and there's no learning curve to keeping them.
One thing about goats - they far prefer brush to grass, so be sure to fence in some brushy areas for them to browse or they will be breaking loose to go find it. We really ought to get some goats in here to bring down the brush in our newly cleared areas - but I'm pushing my numbers with just the sheep I've got. Plus, *whispering* I hate goats. Blech. 
Goats also need good minerals with lots of copper. Southern States carries an excellent protein block with the right minerals, plus the loose minerals you will need. You'll want to put those out anytime the goats are separate from the horses. The horse mineral is okay for them, but it doesn't have enough copper. Goat mineral is okay for horses but it's better to have horse mineral for horses - plus it's typically kept up higher (not that goats have trouble climbing stuff!!!). And you never want to put a goat protein block out for horses because they are usually from 17 to 25% protein - that will make a horse colic!
Goat colic is different from what you see with horses. It's caused by different things, but alfalfa will cause something called "frothy bloat." In it, high amounts of protein make it difficult for the gas in the rumen to diffuse out of the liquid contents. Instead, it stays mixed in like a washing machine with too much or the wrong kind of soap in it. The gas can only go up, not out the back way like with non-ruminants like us. So the poor goat or sheep starts to literally blow up. Eventually the expanded belly gets in the way of breathing, presses on the heart, and the animal dies of suffocation.
You can solve this problem, if you catch it early enough, by feeding the goat a soap solution! The soap breaks down the tension in the bubbles and the gas comes to the top like it's supposed to. Any type of bloat, in extreme cases, can be corrected by using a tube that punches a hole in the animal's side and lets the gas "out the window" so to speak.
The other kind of bloat is caused by too much carbs, among other things. Corn is almost pure carbs and very little protein - about the exact opposite of the goat's ideal diet.
Goats do best on high protein diets - ideally supplied by leaves and green branches - but the equivalent is an overall diet in the range of 17% protein.
Oy. Get me talking about ruminants and you'll never shut me up!
Becca Shouse: Irena Farm, Semora, NC
Cord, Ted, Gus, Zhi, Maggie, Lynn, Lu, Min and Tully - and Sam!
Waiting: Bubo & Ben
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