Sneezing/screeching coughing sick chickens

[FLChickmagnet]

I've had about 7 chickens get sick and die this year from this issue.

Now a month later, another is Sneezing/screeching coughing every 30 seconds. It looks painful and when shes not doing that, she opens her mouth a lot too but no sound comes out. She is getting lethargic and her eyes look dulled and sickly. Still eating but less and less it seems.

treatment so far...
i've isolated her in a cage.
colloidal silver in her water.
fenbenzadol and ivermectin gel under her wings every day
covered her in diatomaceous earth
oregano oil and tumeric in her water and also rubbed on her


please help me save her if you have ideas

 

[nuthatched]

She needs an antibiotic, from a vet or online. Here's a link for you.
https://jedds.com/products/tylosin-powder
What was the SafeGuard/ivermectin supposed to do for her? Especially under her wings? That's an odd treatment I've never heard of.
Why did you coat her in d.e?

 

[Eggcessive]

I would stop the fenbendazole and ivemectin right away. Those are not given under the wings, they are not treatment for a respiratory disease, and they may be overdosed. Do you see any bubbles or foam in either eye of the sick birds? Are they gasping, wheezing, or having rattly breathing. How long have the deaths and illnesses been going on? Had you added any new birds just before they started getting sick? Respiratory diseases can be viruses, such as infectious bronchitis or ILT, or they can be bacterial such as MG, coryza, others. Do you have any Tylosin to treat for possible MG/crd?

Ivermectin is not approved for poultry, but it has been used to treat worms in the past, or mites/lice. It is usually given on the back of the neck, like a spot on medicine for dogs and cats.

Fenbendazole 10% goat wormer or horse paste is given orally for 5 days as a worming medicine. Dosage for gape and other worms is 1/4 ml per pound for 5 days.