Pro'bly lost it in a fight or something. It will grow back. Consider your hens lucky! 3 years old is kinda getting up there in age for a chicken though. He might not be much good for breeding, if that's what you want in the spring.
The birds can live a long time, but that doesn't necessarily mean that they are fertile a long time. For example, I have two three year old banty hens, and neither one has laid an egg for a LONG time. I have a roo the same age, who has his turn with the ladies plenty, and only twice the whole summer have I gotten a chick that is obviously his offspring (out of about 40 chicks).
I think any kind of roo can probably be tamed. Lots of treats and such would help I bet. I've never had a full-sized roo.