Honestly, though, I'm not sure it makes that much of a difference. I had a friend in South Dakota who built all pipe and wood fences around her horse pastures. Religiously scouted every inch of every piece of ground for stray wire or other sharp objects. She had the highest vet bills of anyone in town. It's like the harder she worked at keeping them safe, the more determined her horses were to prove it wasn't possible.
Of course colts are the worst, because they're flighty and unpredictable and still learning what things in their environment bite back. After years of raising babies we've developed an attitude much like that of a new car owner. It's not a matter of when you get the first scratch, just how soon and how bad and pray the thing isn't totaled.
Nearly every horse we own has a visible wire cut scar. Ember's is on her left foreleg from when she was three:
Sweetgrass had a few minor encounters in her early years, but the major damage to her left hock was done when she was eight or nine. Usually this kind of injury happens when there are horses on both sides of the fence, a situation we go to great lengths to avoid if the fence in question isn't solid wood or pipe because they tend to bicker and either strike or kick, resulting in a leg over the barbed wire. That wasn't the case where Sweetgrass was pastured. My sister never could fathom why she stuck her back leg through the fence. She did heal, though, despite slicing the whole front of the joint open and exposing tendons.
The latest casualty is our new colt, Captain, who had an encounter with a fence while we were gone to the lake over the Fourth of July. Because that's the other given with horses. They generally do the stupid stuff when you're not looking. Luckily this was just a flesh wound, not pretty to look at but no damage below the surface.
One of the worst episodes was when Vegas was a youngster. Something spooked the whole herd and they ran through a fence, tore down fifty yards of wire (my dad guesses it might have been a moose since one had been spotted in the area and horse are scared to death of them). Several suffered major cuts. Vegas laid his neck wide open, two long, parallel gashes. We couldn't imagine him ever healing, and if he did assumed he'd have huge, disfiguring scars. And now? All that's left is a faint crease and a dimple.
Oh, and that bumper sticker on the rear door of the horse trailer? That's left over from the days when we lived in Oregon and regularly drove through places like Portland and Seattle to get to rodeos. Back when real fender benders were more of a risk than the equine kind.