ASPERGILLOSIS (BROODER PNEUMONIA)

ASPERGILLOSIS
(BROODER PNEUMONIA)
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Affects most avian species
Important in poults, chicks, and quail.
Is a serious problem in penguins in zoos.
ETIOLOGY
Aspergillus fumigatus
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Spores from contaminated incubators,
feed, litter can penetrate broken shells.
Large dose to infect
Probably not bird to bird.
INCUBATION PERIOD
8 to 12 days in vivo
48 hrs in vitro
COURSE OF DISEASE
2 to 3 weeks
may linger
MORTALITY
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Depends on age
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Up to 100% under brooder
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Other diseases aggravate
METHOD OF SPREAD
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Inhalation of spores 1. Contaminated eggs in incubator
2. Dusty litter and ranges.
Spreads readily under brooder
If clinical signs occur after 7 days of age,
consider farm rather than hatchery exposure.
Contaminated egg
Contaminated Egg
Contaminated Egg
Contaminated Egg
Contaminated Litter
COMMENT
• Usually a young bird disease:
• Exposure in the hatchery or because
they are so close to new litter material,
they inhale spores.
CLINICAL SIGNS
1.
Rapid gasping respiration (without rales)
2.
"Starve outs", emaciated
3.
Blepharoconjunctivitis yellow caseous
pellet in eye
4.
Encephalitis common in turkey poults but
rare in chickens
Affected chicks
Gasping chick
Gasping chick
Nervous signs
CNS Signs
CNS signs
POSTMORTEM FINDINGS
1.
Round yellow caseous granulomas on air sac,
throughout lungs.
“Pearl disease”
2.
Occlusion of trachea
3.
Occasionally green mold growth on air sacs or in
lungs
Air sac lesions
Nodules in air sacs
Air sac lesions
Lung lesions
Lung lesions
Blocked bronchi
Tracheal plug
Tracheal plug
Brain lesion
Nodules in brain
Ocular lesions
DIAGNOSIS
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Typical lesions
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Culture on Sabouraud's dextrose agar w/added
chloramphenicol.
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Identify and classify fungal growth (Light
microscope).
Colonies on Sabaraud’s agar
Conidia
DIAGNOSIS (CON’T.)
• Histopathology to demonstrate fungal
hyphae in tissue.
• Hyphae brownish and have outgrowths in "y"
branches.
Histo 10 x
Branched, septate hyphae
Branched, septate hyphae
TREATMENT
• None specific
• Stress prevention
PREVENTION
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Remove source of infection
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Use high quality litter with little bark
Collect eggs often to prevent cracks
Keep clean litter in nests
Do not set cracked eggs
Fumigate incubators and hatchers
Add antifungal agents to feed
Treat litter w/ fungistatic/cidal agents (TBZ (Folatech), propronic
acid, Clinafarm in the hatchery)
General clean up - disinfection between grow out.