The end of December I had a chicken (Sex Link; 3 years old) start acting sick. She kept her feathers puffed up and was lethargic. I isolated her but within 2-3 days she died on Jan 3rd. Then another started with the same symptoms and I treated her with antibiotics I had on hand added to her water....she lasted several days but on Jan 12th, she died. I called my vet but he told me he would not be much help because he was not good at anything to do with chickens (failed Chickens 101, I guess); so I checked back with this forum and purchased some Corid to treat for what I diagnosed as coccidiosis (there was yellow froth near their droppings and some loose stools). Started them all on that Sunday, Jan 19th with today being day # 4 of the 5-day treatment. Yesterday I noticed another chicken staying on the floor of the coop with her feathers puffed up but then acting normal outdoors later. Today I isolated her with a heater and treated water in hopes to get her better but it appears she is headed in the same direction as the other two. I started with 9 chickens in this coop and yard and am down to 7 with this one being questionable for survival. One last thing, we treated their coop and yard (which is 80' x 80') with Diatomaceous Earth on Sunday because I figured after 3 years it needed to be "disinfected". Is there something else I should use for it, what about Lime? Also, how do I find out what to do next to save the remaining chickens since my vet has bailed out on me?