I haven't seen him covering the hens, but that doesn't mean that he isn't. He does seem to spend more time hiding out in the coop than he used to. I'd like to let my broody hens set, but I don't want to waste thier time on infertile eggs. A lot of things can cause this, from cancer to just a general malaise, but anemia would be my first guess. Check him for mites, mites and lice can suck a lot of blood out of a bird.
Internal parasites can be a problem too.
At two years of age he could be infested with quite a host of parasites. This is a private posting area. A valid username and password combination is required to post messages to this discussion.