I let pups bay at a penned hog starting at six months, letting them see it about once a month until they are 10 months to a year. Then, they go to the woods, depending on how mature I think the dog is. Baying a penned hog means nothing when you want dogs to "find" hogs in the woods.
My older dogs won't notice a pig in a pen.
A hunting dog is going to hunt no matter what. Pen don't have anything to do with making a dog hunt or not hunt.
I agree with that, I just like to give a young dog an idea about what I want him to hunt. He would just soon run a deer, rabbit,armadillo, coon, or the first thing he runs across. A hunting dog don't make him a hog dog.