I am a hunter and a houndsman, I have hunted various game including hogs with dogs for over 20 years. People, hunting is a brutal blood sport, when you kill an animal it is never a pretty or nice thing. There are certain areas of the US that if you are not hunting with dogs you are not going to kill very much game, the brush country of Texas comes to mind, those pictures look like they are from there.
Right now I have 3 mountain curs which pound for pound are the toughest things on 4 feet, I hunt squirrels, possums and coons with them. If they catch a coon or possum on the ground you get what you had in those pictures, that is the way dogs hunt, wild dogs included. Ever watched a pride of lions pull down a wildebeast, it's not pretty either. Most houndsman love their dogs and go out of their way to take care of them, look at those pits, they are very sleek and well taken care of and they all have cut collars on.
I do not hunt hogs with dogs anymore, I have no reason too, I hunt them on the ground with a 44 magnum pistol or a .223 rifle. Where I hunt hogs, in south GA, I don't need dogs, if I lived in Del Rio Texas I would. Chris