Yesterday we found a frankly bloody poop on the sidewalk. Everyone acts ok except one chicken that has been lying around and one guinea who started walking backwards yesterday. We have 5 guineas and 4 chickens. They all were raised together and are the same age (born in April). We just got a rooster and hen that are younger than these but not sure how much younger. The two new chickens have been separate from the rest of the flock since arrival 10 days ago. Took the poo to the vet who confirmed coccidiosis and told us to get medicated feed and something to put in their water. I am gonna treat all of them but here is my question--my flock is normally free range. If I keep them cooped and treat them, what is gonna keep them from getting it again? We also are visited by 3 guineas who live up the road as well as wild turkeys in the woods behind our house. We are new to the chicken thing but they are pets to us and we don't want to lose anyone. Any suggestions?