Coccidiosis diagnosis...with respiratory infection?

[Wyorp Rock]

I ran to the store to get Safe-guard and got home and gave her a pea-sized portion in her mouth.

One of the other breeders suggested Duramycin to treat that...one drop for 10 days straight to wipe out any bacterial infection she may have in her lungs. I started that Tuesday morning because I didn't want to wait any longer. B wasn't eating...drinking...and looked weaker and weaker.

Fecal Test Results Wednesday - showed Coccidiosis. Which is odd because I haven't seen any weird bloody poop ANYWHERE.

I was also able to get an appointment with the vet Thursday. She says it's not respiratory at all...but an accumulation of Coccidiosis...and that she's too weak and too far gone, and to euthanize her.

I continued treating B with an undiluted Corid treatment based on her weight. She weighs 28 oz, so figured 1.75 ml would be good for her.

I'm giving it directly - undiluted - based on these instructions: https://www.backyardchickens.com/articles/corid-amprolium-oral-drench-instructions.74391/

The Duramycin is in a dropper, so not injecting it....but rather giving it to her orally. Just a little drop in the side of her mouth.

I've been given so much conflicting information that I'm just winging it here.

Do you have Liquid/Injectable Duramycin? The Powder has been off the market for a long time. If it's injectable, I'm not sure if it should be given orally, it's a drug designed to give to cattle and is given once every three days. Dosing is hard to nail down for the injectable, but it seems the consensus is 0.20ml per pound of weight injected into the breast muscle, then repeated in 3 days. https://www.backyardchickens.com/threads/miracle-la-200-dosage-and-vetrx-for-crd-treatment.631458/

Does she have mucous crusting in her nares (nostrils) or do you see any lesions inside her beak - any bad odors?

Safeguard (Fenbendazole) is dosed by weight not by pea size. Dose is 0.23ml per pound of weight given orally once a day for 5 days in a row.

Corid direct oral drench is in addition to her drinking the mixed Corid water throughout the day. Undiluted Liquid Corid dose is 0.10ml per pound of weight given orally 1-2X a day for 3 days. You mention she weighs 28oz, so the direct oral dose would be 0.175 or just round up to 0.20ml so it's easier to dose.

Mixed Corid solution is 2tsp Liquid Corid per gallon of water given for 5-7 as the only source of drinking water. Don't add any extra supplements/vitamins/electrolytes that contain B1(Thiamine) during the course of treatment.

Is she pooping at all? What's it like?

Work on getting the Corid water into her, adjust your dosing for the Oxytetracycline if it's liquid (Corid is not an antibiotic).
See if you can get her to eat some wet soupy feed once she's hydrated.

I hope she pulls through. If you do happen to lose her, then sending the body for necropsy through your state lab would give you information that may help you treat any future birds that come down with similar symptoms, since this is the second one.