ASPERGILLOSIS

(BROODER PNEUMONIA)

• Affects most avian species

• Important in poults, chicks, and quail.

• Is a serious problem in penguins in zoos.

ETIOLOGY

Aspergillus fumigatus

• 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

• Depends on age

• Up to 100% under brooder

• Other diseases aggravate

METHOD OF SPREAD

• 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

• Typical lesions

• Culture on Sabouraud's dextrose agar w/added chloramphenicol.

• 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

• Remove source of infection

– 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.