Protecting Cage (Exotic) and Aviary Birds Against Exotic Newcastle Disease

by

F. Dustan Clark
Extension Poultry Health Veterinarian
Arkansas Cooperative Extension Service
University of Arkansas
O205 POSC Fayetteville, AR 72701
479-575-4375 fdclark@uark.edu
On October 1, 2002 Exotic Newcastle disease (END) was confirmed in backyard poultry
and gamefowl in southern California. Since that time, numerous backyard premises have been
quarantined for END. The disease has also spread into flocks of commercial layer chickens in
the same area of California. The California Department of Agriculture and USDA/APHIS are
presently working to eradicate the disease. Several counties or portions thereof are under a state
and federal quarantine to restrict bird movement. The disease has also been confirmed in the Las
Vegas, Nevada area in backyard chickens. To date there has not been a problem diagnosed in
exotic cage and aviary birds in these areas. However, these types of birds are susceptible to the
disease and as such are at risk. An outbreak in exotic cage and aviary birds can be extremely
costly. An outbreak in 1980 in Florida cost USDA/APHIS over 1 million dollars to eradicate and
resulted in the death of approximately 8,000 birds and additional depopulation of over 30,000
birds in 23 states.
The causative agent of END is a virus in the family Paramyxoviridae. Infected birds
can shed the virus in the feces and other body secretions and some birds may not be showing
clinical signs. The virus can persist in feces and moist soil for long periods of time. Birds can
also contract the disease by direct contact with infected birds, feces or other body secretions,
exposure over short distances to aerosols from coughing and sneezing, or contaminated
equipment, clothing, etc. This virus has a variable incubation period (17 days or less)
depending on the specie of bird infected, strain of virus, other infections in the bird, various
management factors, stressors, etc. Some exotic cage birds are highly susceptible (Amazon and
Eclectus parrots, Cockatoos, Macaws) whereas others act as carriers and may not develop
clinical signs (finches, Lories, Mynah birds, Budgerigars). The clinical signs of the disease are
also variable and may resemble other diseases. Some birds contract the disease and die without
showing signs whereas others develop disease and recover. Nervous system signs such as
tremors, shaking of the head, twisting of the head, and paralysis may be present. Other signs that
can be observed are depression, lack of appetite, weight loss, diarrhea, difficulty breathing, eye
and nasal discharges, coughing, etc. Birds may or may not develop lesions associated with the
disease. Lesions observed can be small hemorrhages on fatty tissues or in the digestive tract and
respiratory tract. The spleen and liver may also be enlarged in some birds. However, since the
symptoms and lesions are not exclusive for END the disease must be differentiated from similar
diseases. The disease can be diagnosed in live birds by virus isolations from fecal, choanal,
cloacal, and tracheal swabs. In birds that have died the virus can be isolated from various tissues
such as lung, brain, intestines, etc. Serological testing can also be used as a screening test. There
is no effective cure for the disease and the disease is eradicated by strict quarantine, surveillance,
and depopulation. The best way to reduce the risk of introducing the disease into your birds is by
following Biosecurity practices (Additional information on Biosecurity is available at http://www.uark.edu/depts/posc/avianindex.html) . Some examples of such practices are :
1. Do not purchase birds that appear sick or that may have been illegally brought into the
country.
2. Avoid sick birds if at all possible.
3. Practice good hygiene principles.
4. Clean and disinfect thoroughly.
5. Do not visit aviaries that have sick birds.
6. Prevent rodents and wild birds from entering the facilities where birds are kept.
7. If you visit a facility with birds that may be suspected of being infected it is important to
change clothes, shower, wash your hands and thoroughly disinfect all items taken on the premise
before contact with your birds.
8. Report signs of disease immediately and get a veterinary diagnosis immediately.
For additional information or to report disease contact any of the following:
County Agent, Local veterinarian
State Veterinarian State Veterinary Diagnostic laboratory
Extension Veterinarian