Sounds like a respiratory infection such as Mycoplasma Gallisepticum (MG).
Chronic Respiratory Disease (CRD), or most commonly known as Mycoplasma Gallisepticum (MG). MG is a bacterial infection of poultry, affecting all different species of birds. This disease is most commonly given from infected parents to the offspring, as the MG bacteria can be transmitted vertically into the eggs of developing embryos, making any chicks that hatch, always infected and sick with the bacteria. So please don’t ever breed from your sickly infected flock to sell or giveaway chicks/hens/roosters to anyone. You can freely choose to hatch for yourself, but you should not ever sell and or giveaway any extra roosters as you’ll just be giving someone else your flock’s disease, causing them a devastation. MG is a permanent lifelong chronic disease- meaning, that you can treat or have the symptoms go away, but whenever the bird gets stressed again, the symptoms will keep coming back or get worse. All birds (even recovered birds) remain lifetime long carriers of the MG bacteria, spreading and shedding it through their feces, feathers, dander, respiratory secretions and other bodily fluids. This is a serious permanent lifetime disease of poultry and is incurable, but treatable with antibiotics. Since MG is caused by a bacteria, antibiotics can help keep symptoms at bay until the symptoms resurface whenever birds become stressed again. Keep in mind that over-use and/or misuse of antibiotics also creates antibiotic-resistant bacteria, making the disease harder to treat than before. It’s critical in any livestock animal, especially poultry, to get any sick or symptomatic birds tested to find out which specific disease they have as soon as possible. That being said, most choose to cull all birds, disinfect and start over fresh. If you’d rather not, then the other option is to keep a closed flock- no new birds into your flock and no birds leave your sick flock. If you choose to start over, always quarantine any new birds that you decide to bring into your flock, 30 day quarantine isn’t always enough, therefore, it’s best to do a 60 day quarantine AWAY from your healthy birds, in another area.
Here's more information about MG:
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https://extension.umd.edu/sites/ext... Mycoplasma gallisepticum (MG) Infecti....pdf
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https://www.freedomrangerhatchery.com/blog/protecting-your-flock-what-you-need-to-know-about-mg-ms/
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https://afarmgirlinthemaking.com/respiratory-conditions-poultry-mycoplasma-in-chickens/
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https://www.maine.gov/dacf/ahw/animal_health/documents/backyardpoultry/Mycoplasma Factsheet.pdf
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https://www.oie.int/doc/ged/D9107.PDF
List of testing and necropsy labs for poultry & other animals:
• List of US Poultry Labs -
https://www.heritageacresmarket.com/poultry-necropsy-labs/
• List of Poultry Authorized Labs (NIPIP) -
https://www.poultryimprovement.org/documents/AuthorizedLaboratories.pdf
• Zoologix PCR testing for livestock (poultry, equine, bovine, avian, etc) -
http://www.zoologix.com/avian/index.htm
• USDA Diagnostic Tests -
https://www.aphis.usda.gov/aphis/ou..._Lab_Information_Services/SA_Diagnostic_Tests
• Research Associates Lab (RAL) -
http://www.vetdna.com/test-type/avian-bird
• Poultry Health Services Diagnostic Tests -
https://www.poultryhealthservices.com/lab/tests/
I wish you good luck and I hope your birds get well soon!
