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 effective.
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:
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.