I have to say I was really looking forward to the mounts being added into the game, but the more I do it just leads to frustration and disappointment.
To save someone resources and stress, have a shelter before you even go after a horse, if you catch a horse before you have a shelter up, you will not be allowed to mount the horse.
To catch a boar, no matter how many times you shoot the thing and it runs away it won't work unless it ran away on the first hit. Sometimes they are afraid on the first hit and it's a pain in the butt looking for one that is.
The deer, the bloody deer can't stand still long enough to catch, and when you finally do get the thing to stop, it runs right towards you.. gets scared and runs off again. I wasted way to many hours and I got so frustrated i started killing the ones that didn't behave. Finally I got one by making a maze of fences and herding onto my land.
So now i'm all excited i finally have a mount!! Nope! You have to dismount to do anything, still get attached by a bear, bleeding to death on the back of your animal, only to find out you can't heal yourself when you are mounted. Come on, you can't open doors, can't attack anything. I'm sorry but if i'm riding a horse in the real world, I can shoot a darn bunny without having to dismount, why can't I leave a trail of dead bodies behind me as a run along? Take all the fun out of it..