Wow that's great! I hadn't ever heard of chickens eating the slugs! I am glad it's working. I was also gonna mention the ducks and saw you weren't for them at the moment (hey, get it... I have them and I am not sure if I am for them... haha).

Any organism can give anything a parasite. People are silly. A lot of people also say that "giving them earthworms can give them worms". Really people? The heck do you think they're gonna eat at all?!