Mycoplasma

About Mycoplasma

Mycoplasma gallisepticum can cause respiratory disease in chickens. Other diseases can produce similar signs, so examination and testing may be needed. Birds can remain carriers even after their signs improve.

Mycoplasma — illustrative photograph — Illustrative photograph. Appearance alone cannot confirm a diagnosis.

Signs to look for

Sneezing, coughing or noisy breathing
Discharge from the eyes or nostrils
Swollen areas around the eyes or reduced activity

What can cause it?

Infection can spread between birds and through infected eggs. Close contact and contaminated equipment can contribute to spread, and stress or other infections may make disease more apparent.

First steps and veterinary care

Contact a poultry-experienced vet and separate affected birds if safe. Use dedicated equipment, attend healthy birds first and clean hands and footwear. Do not move or sell birds while unexplained respiratory illness is being investigated.

Prevention and everyday support

Discuss sourcing, quarantine and testing with your vet. Keep housing well ventilated and avoid overcrowding. Treatment may reduce signs without eliminating infection; medication choices and egg withholding periods need veterinary direction.

When to seek help

Open-mouth breathing at rest, severe distress or rapid deterioration are emergencies. Multiple sick or dead birds require immediate advice and reporting through the Australian Emergency Animal Disease Hotline.

Sources and further reading

Content checked 10 November 2026. General information; not an individual veterinary assessment.

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Everyday care essentials

Plan dry bedding, safe perches, good ventilation, fresh water and an appropriate complete ration. A suitable home supports your flock’s day-to-day wellbeing.

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Prepare for a veterinary call

Record changes in appetite, droppings, laying, movement and breathing. Tell the vet about recent arrivals, feed changes and any medicines already used.

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Support for your flock

If your chicken is unwell, contact a poultry-experienced veterinarian. Take notes on signs, when they started and how many birds are affected. Photos or a short video may help your vet.

For general questions about preparing a home for your birds, browse our care guides or visit our contact page.