Introduction: Exotic
Newcastle Disease (END) is a highly contagious viral disease of many
species of birds. END can cause high
mortality (up to 90%) in chickens. Psittacine as well as other caged birds are
also susceptible to END. Birds
illegally smuggled into the United States are not quarantined and tested by
United States Department of Agriculture (USDA) and birds may carry END
virus. Therefore, END is a threat to
the cage bird industry. An END outbreak in cage birds in Florida in 1980
resulted in the death of approximately 8000 birds and the depopulation of
30,307 birds in 23 states that cost the USDA $1,166,253.00.
Symptoms: Are highly
variable and non-specific in cage birds.
One of the classical symptoms of END is tremors and involuntary shaking
of head and body when the bird attempts movement. Other symptoms may include
anorexia, depression, diarrhea, paralysis, twisted neck, respiratory
difficulty, ocular discharge, loss of weight, etc. Similar symptoms may be seen with other
avian diseases also. Therefore, confirmatory testing in a laboratory is
necessary for a diagnosis of END.
Incubation period: May
vary from 2 to 17 days depending on the species of the bird, management
factors, concurrent infections, etc.
Cockatiels, budgies, amazons, cockatoos are highly susceptible. Other species such as Lory’s, macaws,
canaries, finches, Mynah’s, African grey’s may not show symptoms but may act as
carriers.
Lesions: Range from none
to hemorrhages in the digestive and respiratory tracts, plaques in the pharynx
and glottis. Other lesions may include
hepatosplenomegaly and ascites.
Diagnosis: Can be made in
live bird by virus isolation from feces, cloacal and tracheal swabs. Lung,
intestine, brain, liver and spleen are suitable organs for virus isolation.
Serology can be used for screening.
Treatment: There is
no treatment for END. Vaccination is not advisable.
If unusual mortality is
observed notify END task force hotline 1-800-491-1899. Submit dead birds to one of the CAHFS
laboratories located in:
San Bernardino: Tele:
909-383-4287
Fresno: 559-498-7740
Turlock: 209-634-5837
Davis: 530-752-8700
The premises are quarantined
until diagnosis is made.
END is a federal reportable disease and any person or
veterinarian who suspects it should report the disease to the state
veterinarian.
Prepared by Dr. H. L. Shivaprasad, California END task
force, 10/24/02.