You ask good questions!
I don't have the answers. But my farm friend up the road has goats in with her guineas, turkeys, ducks, geese, and chickens. They all range together. The fowl all have access to the hog pen, also. And cattle section. Do I'm sure they're transferring things from everywhere.
She said with the goats that if their poop gets even a little soft age immediately worms them. So... There's some info.