Haemorrhagic enteritis (HE)
Occurrence: Worldwide, wherever turkeys are raised.
Species affected: Turkeys (most common) and chickens.
Age affected: 4 weeks or older.
Causes: HE virus is a double stranded DNA Adenovirus.
Effects: Incubation period is less than 24 hours. Depression, bloody droppings, dark red to brownish blood on the skin and feathers around the vent can be seen. Mortality is 10-80%.
Turkeys of 4 weeks or older may develop this acute viral disease. HE virus is an unenveloped, icosahedral, double-stranded DNA virus. It replicates in the nucleus forming basophilic inclusion bodies (viral factories seen under light microscope).
Mode of transmission
Spreads orally from infectious faeces or litter.
Incubation period is less than 24 hours. Depression, bloody droppings, mortality (10-80%), dark red to brownish blood on skin, feathers and around vents can be seen.
The skin and flesh are pale, anaemic and dark in colour. The jejunal mucosa is red and highly congested, spleens are enlarged, friable and mottled, lungs are congested and vascular organs are pale, and the livers are enlarged with haemorrhage.
Clinical signs, and gross and microscopic pathology are useful.
Intranuclear inclusion bodies in the reticuloendotheial (RE) system and intestine are diagnostic. Spleens show RE hyperplasia and inclusion bodies. ELISA or AGP tests can be used to detect antibody.
It simulates leukosis, reticuloendotheliosis, fungi, toxicities, and coccidiosis.
Treatment & control
Use of a live vaccine in drinking water at 4 and 6 weeks of age can prevent the diseases.