Gapeworm in chickens are pretty rare, especially if you live in the northern parts of the world. Obviously it’s warmer now, so there IS a chance, but it’s still unlikely.
I suggest doing the Q-tip test like
@azygous had mentioned. Other causes to this would be an impaction of the crop, sour crop, obstruction of the trachea or esophagus or even a respiratory infection. Respiratory infections that can cause gaping primarily would be
Aspergillosis,
Infectious Laryngotracheitis (ILT) or
Infectious Bronchitis (IB). Antibiotics will not work on any of these diseases as one is caused by a fungus and the others are caused by a virus. Another cause would be
Mycoplasma Gallisepticum (MG) or also known as
Chronic Respiratory Disease (CRD) which is also a respiratory infection of poultry and THE MOST COMMON respiratory disease of all that exist.
What is good about MG is that it is easily treatable with antibiotics as it’s caused by the
Mycobacterium bacteria. While it’s treatable, it is not able to be cured meaning that all birds with symptoms and those exposed, will be lifetime infection carriers. I don’t suggest breeding to sell from your flock as MG can be passed down to the offspring via the eggs. Yes, eggs are still safe to eat as long as there is no antibiotic withdrawal.
Unfortunately, if he passes away, I would highly suggest that you send his body off for a necropsy testing so you can know what the cause was and how to keep your other exposed birds safe and healthy. You can get testing done from the links I’ll post below. If you are in the US, you can always call your state of agriculture and ask about getting a necropsy done. Some states offer to do the necropsy for free, while others do not.
Here are some great and highly recommended testing facilities that will test your birds live or by a necropsy:
RAL -
http://www.vetdna.com/test-type/avian-bird
Zoologix -
http://www.zoologix.com/avian/index.htm
Poultry Health Services -
https://www.poultryhealthservices.com/lab/tests/
Some information on the diseases that I mentioned above:
Mycoplasma Gallisepticum (MG), also known as Chronic Respiratory Disease (CRD):
-
https://www.maine.gov/dacf/ahw/animal_health/documents/backyardpoultry/Mycoplasma Factsheet.pdf
-
https://www.oie.int/doc/ged/D9107.PDF
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https://afarmgirlinthemaking.com/respiratory-conditions-poultry-mycoplasma-in-chickens/
Infectious Laryngotracheitis Virus (ILT):
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https://www.agriculture.pa.gov/Animals/AHDServices/licenses-certificates/Certified Poultry Technician License/Documents/Infectious Laryngotracheitis Virus (ILT) Facts.pdf
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https://www.oie.int/doc/ged/D9312.PDF
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http://www.omafra.gov.on.ca/english/livestock/poultry/facts/ilt.htm
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https://www.tahc.texas.gov/news/brochures/TAHCBrochure_ILT.pdf
Infectious Bronchitis Virus (IBV):
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http://extension.msstate.edu/publications/infectious-bronchitis-commercial-chickens
Aspergillosis also known as Pneumonia in poultry:
-
https://www.freedomrangerhatchery.c...illosis-plus-how-to-prevent-it-in-your-flock/
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https://extension.psu.edu/aspergillosis-in-poultry
I wish your birds well and I hope that the information that I’ve provided will help you. Good luck and I hope your bird gets well as soon as possible!
