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Brooder Pneumonia

Acute Aspergillosis

Aspergillosis is an infectious, non-contagious fungal disease. The disease is caused by infection with species belonging to the Aspergillus genus. Aspergillus fumigatus is the most common species isolated from infected birds, followed by A. flavus. Aspergillosis primarily affects the respiratory tract however it can also cause eye infections. The disease manifests in two different forms---as an acute or chronic infection.
  • Acute form: Acute aspergillosis, also referred to as Brooder pneumonia is characterized by severe outbreaks in newly hatched chicks and is associated with high morbidity and high mortality rates.
  • Chronic form: Chronic aspergillosis, is a disease that occurs sporadically in adult chickens.
What are the clinical signs?Clinical signs in chicks usually start to present within 3-5 days after exposure. Affected chicks will initially show signs that they are having difficulty breathing, with an increased respiratory rate and open-mouth breathing. If chicks survive (5 to 50% usually will die the first 1-3 weeks of life), they will develop a loss of appetite, increased thirst, lethargic behavior, and extreme weakness. Some will develop eye swelling leading to blindness, ascites, or torticollis (where they are observed twisting their neck to one side). In other cases, chicks may be subclinically affected initially, showing no signs of infection, but later develop breathing problems as they increase in body weight which proportionally increases demands on the functional capacity of their lungs.

Where is the fungus found?
Aspergillus spp. are naturally found in small concentrations throughout the environment---in the air, soil, bedding, etc. Higher amounts of Aspergillus spp. develop through the presence of dust and mold.

How is it spread?
Aspergillosis is not a transmissible disease. Chickens are infected through environmental exposure. Aspergillus are opportunistic invaders, and healthy birds are usually resistant to infection unless they are exposed to a massive number in the environment or are vulnerable due to age, concurrent illness, chronic inflammatory condition (such as bumblefoot or other prolonged condition) or stress. Sometimes multiple flock members become infected at the same time from exposure to the same source.


Difficulty breathing
Reduced feed intake
Increased thirst
Open-mouthed breathing
Torticollis (twisted neck)
Eye swelling
Enlarged abdomen


  • History
  • Clinical signs
  • Laboratory tests
  • Necropsy


Itraconazole10 mg/kg administered orally, twice a dayK Marx
Amphotericin B1 mg/kg administered IT, TID + 1.5 mg/kg IVK Marx
Ketoconazole60 mg/ml
Tarwood (Loxostylis alata) extract200 mg/kgM Suleiman, N Duncan, J Eloff, V Naidoo
Ant. Tartrate30C once a day for 3 daysK. Glos 2015
Drosera rotundfolia30C once a day for 3 daysK. Glos 2015


  • Not purchasing or shipping chicks in the mail
  • Keep warm, do not expose to cold
  • Do not overcrowd birds
  • Daily removal of any leftover uneaten feed
  • Inspecting feed regularly for signs of mold.
  • Frequently move feeders and water dispensers to different areas and place on elevated platforms to minimize spillage
  • Conduct regular air quality tests
  • Clean droppings from brooder daily, to reduce build up of ammonia fumes.
  • Reduce the potential for condensation on cold surfaces (i.e., windows, piping, exterior walls, roof, or floors) by adding insulation.
  • Exposing chicks to dusty conditions

Scientific References

    Age Range

    Newly hatched chicks are highly susceptible.

    Risk Factors

    • Shipping chicks in the mail
    • Exposure to damp, poorly ventilated areas
    • Exposure to moist, moldy or dusty bedding and/or straw or hay bales
    • High air temperatures combined with high humidity
    • Exposure to dust
    • Build up of ammonia, caused by excessive accumulation of feces
    • Cold stress
    • Any accumulation of moisture