Samantha-I am so sorry. I went thru that with a pullet I brought home and quarantined. I treated her and treated her (had a fecal flotation sample come back positive so knew I was on the right path) Tried a couple medications-we ended up having to put her down too. I sent her in for a necropsy and the only thing they found was she was full of Cocci...and for some reason just couldn't pull thru it/get rid of it. You did everything you could! Just know that if it was Cocci, it will remain around on your ground , dirt, etc....Cocci is everywhere all the time, wild birds can even pass it to your flock. As the vet explained to me, the trick is to keep it in balance. Young, weak, sick, or old birds are the most susceptible to having the balance get out of hand, so just keep your eyes open if you have any of those birds and they show similar signs so you can treat.
ETA: You can get a fecal flotation test done for under $10 usually through your state university lab. (You jsut collect several fresh poops, mix them together in a plastic baggie and mail it in.)
