Avian Health Program   Return to Avian Health Program
However, there are diseases that can cause serious problems and expense to your poultry enterprise because poultry diseases are numerous, and easily spread.

A disease by definition is a deviation from normal health. The effects of disease can range from reduced production, loss of energy, to death. Diseases can be infectious (contagious) or non infectious. Infectious diseases are caused by microscopic pathogens (germs). In backyard poultry there are four main classes of pathogens: viruses, bacteria, fungi and parasites. Parasites can be internal as with worms & protozoa (coccidian) or external as with mites and lice.
External Parasites

Poultry Mite



Poultry Louse

Internal Parasites

Tape Worm

Protozoa can cause
diseases such as:
Coccidiosis
Blackhead

Round Worm

Microscopic fungi cause
diseases such as:
Aspergillosis
Mycotoxicosis
Moniliasis

Microscopic viruses cause
diseases such as:

Avian Influenza
Newcastle Disease
Avian Pox
Infectious Bronchitis
Marek's Disease

Microscopic bacteria cause
diseases such as:
Mycoplasmosis
Fowl Cholera
Pullorum Disease
Fowl Typhoid
Botulism
Sample questions:
There are numerous poultry diseases that are easily spread and can cause serious problems to your poultry enterprise.
a) True
b) False
What are the four main classes of pathogens (germs) that cause poultry disease?
a) rodents, hand sanitizer, biology 101, antibiotics
b) soap, water, disinfectant, dirt
c) viruses, bacteria, fungi, parasites
d) vehicle tires, your neighbor, dirty clothing, dirty shoes
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