This is my first time having chickens butchered and I need to make sure I'm doing it at the right time. I have 3 Sussex Roos which are 16 weeks old. They have been free ranged and supplemented with grower feed (nonmedicated). There is a local lady who butchers for $2.00 per bird. It seems to be a good price for the labor and time involved, yes? This is a trial for us to see if we like the taste of fresh chicken... Do I need to worm these birds first? Or do anything else prior to butchering?