What killed this limb?


5 year old buck +
What did this?
I was walking the orchard and about 3' of a limb was hanging with black leafs. Pear tree. It was barely hanging so I grabbed it and took a look. Hole down the middle and what likes like a clean cut going out. Didn't see it anywhere else on any of the other trees.
I blamed my nephew and friend when they were kids because I found an oak tree with similar marking on a broken branch. But believe it or not it was the wind. I've have since noticed hundreds of branches missing from smaller trees with the same kind of markings.
Mine occasionally loose limbs just like that they very nearly look cut off except for the bark. I believe there is a name for it and some verities are more prone than others but it’s name escapes me.