When ever you butcher out poultry you should check your parasite level. cut open intestines. All animals have paarasites, even us. The trick is to keep them at low levels that do not effect health of the flock. I know my birds probably have parasites, but, to date I have never seen one during butchering. When ever you see intestines that are a bit too colored, they probably have some kind of parasite. Just get in the habit of checking intestines when you butcher.
Keeping worms at a reasonable level is pretty easy for poultry..they need frest air, clean water, good food, exercise, and things like ACV, Oregano, pumpkin seeds, cucumbers, apples..all kinds of thngs help to keep the intestines working well and making organs inhospitable to worm over load.