Causative agent
- DVE or DP virus, family Herpesviridae
Differential diagnosis
- Duck virus hepatitis
- Pasturellosis
1. History taking
- Natural infection is limited to members of the
family Anatidae (ducks, geese and swans)
- Mortality 5-100 %
2. Clinical examination
- Photophobia
- Loss of appetite, ataxia
- Watery diarrhea
- Nasal discharge
- In laying flocks, 25-40 % drop in egg production
3. Necropsy
- Depends on species affected, age susceptibility,
virulence of virus
- Vascular damage with visceral tissue hemorrhages
in liver, pancreas, intestine, lung and kidney
- Specific digestive mucosal lesions : oral cavity,
esophagus, ceca, rectum and cloaca covered with
yellow-white crusty plaques
- Mottled spleen, petechiae in thymus, redden bursa
of Fabricius, hemorrhagic intestinal annular bands
- Pale to dark bronze or bile color liver with white
foci
4. Histopathological observation
- Disruption of endothelial lining of blood vessels
and extravasation of blood pass into surrounding
tissue
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- Digestive lesions : hemorrhage, necrotic, and
plaques with intranuclear inclusion bodies
- Lymphoid tissue of intestinal annular band,
esophageal, proventriculus sphincter and spleen
become hemorrhage
- Karyorrhexis and pyknosis of lymphocytes
- Necrotic foci of liver, swollen necrotic hepatocytes
with intranuclear inclusion bodies
- Congestion, hemorrhage and necrosis in oviduct
5. Antigen detection
Specimen : esophagus
Method : FA test on cryostat section and observe
fluorescence in the nucleus and
cytoplasm of epithelial cells of the
esophagus
6. Viral isolation
Specimen : liver, spleen
Method : 1. duck embryo inoculation at 9-14
days of age by CAM route and
observation of extensive
hemorrhages with necrotic liver
2. DEF inoculation and CPE observation
(enlarge necrotic rounded clump
cells)
7. Virus identification
- FA test
- VN test
Control
: Vaccination with live attenuated vaccine
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