Why Is My Chicken Sneezing?
A few of the product links in this guide are affiliate links. If you buy through one, Ambitious Harvest may earn a small commission at no extra cost to you, which helps keep these guides free. We only point to gear we would use in our own Santa Cruz garden. As an Amazon Associate, we earn from Read our full disclosure.
Why Is My Chicken Sneezing?
Occasional sneezing is normal and usually caused by dust, but persistent sneezing combined with nasal discharge, wheezing, or lethargy can signal a respiratory infection that needs attention. UC Davis Veterinary Medicine identifies Mycoplasma gallisepticum (MG) and infectious bronchitis as the two most common respiratory diseases in backyard flocks.
The most frequent, and least concerning, cause is simple dust irritation. Chickens scratch and forage in dry soil all day, and our Santa Cruz summers create plenty of fine dust in the run. Dusty bedding (especially if you use straw that has gone powdery) and poor coop ventilation also contribute. If the sneezing happens mainly in the coop or after a dust bath and the bird otherwise looks healthy, active, and is eating normally, dust is likely the culprit.
Ammonia buildup is the other common environmental cause. If your coop bedding is not changed often enough, ammonia from droppings accumulates at floor level, right where your birds breathe while roosting. You should not be able to smell ammonia when you open the coop door. If you can, it is time for a full bedding change and better ventilation. UC ANR recommends cross-ventilation near the roofline to let ammonia and moisture escape without creating drafts on the birds.
When sneezing comes with other symptoms, pay closer attention. Bubbles in the corner of the eye, swollen sinuses, rattling breath sounds, or mucus from the nostrils point toward respiratory infection. MG in particular is widespread in backyard flocks and spreads through direct contact and shared water. It is chronic, meaning infected birds carry it for life even after symptoms clear. This is one reason quarantining new birds for at least 30 days before introducing them to your flock is so important.
If you suspect a respiratory infection, isolate the sick bird in a clean, warm, well-ventilated space away from the rest of the flock. Contact a poultry-knowledgeable veterinarian. In Santa Cruz County, several vets handle backyard poultry. The UC Davis School of Veterinary Medicine also offers diagnostic services through their California Animal Health and Food Safety Laboratory, which can test for specific pathogens from swab samples.
This week: Check your coop ventilation and bedding. If you can smell ammonia at bird height, do a full clean and add ventilation openings near the roofline.
Keep Reading
Frequently Asked Questions
Is an occasional sneeze something to worry about?
Usually not. The most common cause is simple dust irritation from bedding, poor ventilation, or ammonia, and improving airflow often resolves it. If ammonia is noticeable at bird height, do a full bedding change.
When does sneezing signal a real infection?
Be concerned if sneezing comes with bubbles in the corner of the eye, swollen sinuses, rattling breath, or mucus from the nostrils. Those signs point to a respiratory infection that warrants a poultry-experienced veterinarian.
How can I protect the rest of my flock?
Quarantine any new birds for at least 30 days before mixing them in, and isolate sick birds in a clean, warm, well-ventilated space. This matters because some respiratory diseases, such as Mycoplasma gallisepticum, stay with a bird for life even after symptoms fade.
