Newcastle disease is a severe clinical manifestation of infection with Newcastle
disease virus. The disease is seen mainly in chickens.
In chickens,
Newcastle disease often causes high or total mortality in a flock. Chickens may
die without showing any clinical signs of infection.
Common clinical signs of acute infection
Greenish blood-stained diarrhoea
Dehydration
Tremor
Torticollis
(abnormal position and twisting of the neck, limited movements of the
head)
Paralysis
Respiratory
distress
Loss of
appetite
Common post-mortem findings
Hyperaemia and congestion in respiratory tract
Serous or
catarrhal exudates in larynx and trachea
Thickened air
sacs, may contain yellow exudates
Haemorrhagic
lesions in digestive tract: with some necrosis especially in
proventriculus
Haemorrhages
in the intestinal lymphoid nodules and caecal tonsils
Enlarged
spleen
Diagnosis
Presumptive: Based on clinical signs and post mortem findings
Unequivocal: Isolation of virulent Newcastle disease virus from samples
for example blood, bone, spleen, lungs
Sero-diagnosis: Monitoring of antibody levels in acute and convalescent
serum samples.
