Causative agent 
- ND virus, family Paramyxoviridae


Differential diagnosis 
- Fowl cholera
- Avian influenza
- Infectious laryngotracheitis
- Fowl pox (diptheritic form)
- Mycoplasmosis
- Avian encephalomyelitis
- Infectious bronchitis



1. History taking 
- No relationship between the incidence of the
  disease and the age of chickens
- High morbidity and mortality



2. Clinical examination 
- Vary greatly, depending mostly upon the viral strain
  and infected avian species
- Respiratory distress, rale, gurgling
- Twitching of the neck and head, drooping of the
  wings
- Rapid drop and stop in egg production
- Green diarrhea



3. Necropsy 
- Gross lesions are dependent on the strain and
  pathotype of virus
- Proventricular hemorrhages and hemorrhagic,
  necrosis of intestine and cecal tonsils
- Petechial hemorrhages of adipose tissue in
  pericardium, abdomen, etc
- Hemorrhagic lesions and marked congestion of the
  trachea



4. Histopathological obersvation 
- Mucosa of the upper respiratory tract congestion,
  edema and dense cellular infiltration of lymphocytes
  and macrophages

- Degeneration and necrosis in the lymphoid tissue
  such as spleen, thymus and bursa of Fabricius and
  hyperplasia of reticulohistiocytic cells
- Small focal area of necrosis in liver
- Hemorrhagic-necrosis lesions in the intestinal tract
- Hyperemia and endothelial cuffing with
  degenerative change in neuron and ganglia
- Blood vessels of many organs are found
  hyperemia, edema and hemorrhage



5. Serological test 
- HI test (pair sera)



6. Virus isolation 
Specimen : liver, spleen, trachea, brain, cecal
                  tonsil, cloacal swab
Method    :
1. chick embryo inoculation at 9-11 days of age by
    CAC route and observe extensive hemorrhage 2-
    4 days after inoculation
2. CK inoculation and CPE observation



7. Virus identificaton 
- HA test
- HI test



8. Pathogenicity test 
- Mean death time in egg (MDT)
- Intracerebral pathogenicity test (ICPI)
- Intravenous pathogenicity test (IVPI)

Control 
- Good sanitation and management
- Vaccination with live or inactivated vaccines
- Strict isolation of outbreaks and destruction of all
  infected and exposed birds
- Restriction on trade in poultry products, eggs and
  live poultry