HEMORRHAGIC ENTERITIS OF TURKEYS Hemorrhagic enteritis (HE) is a viral disease of young turkeys characterized by sudden onset, depression, bloody droppings, and variable but often high mortality. It is caused by a turkey adenovirus and transmitted through the fecal-oral route. Clinical signs include sudden deaths, bloody droppings, and an enlarged mottled spleen. At necropsy, the intestines are distended and dark purple with hemorrhagic content. The diagnosis is confirmed by finding intranuclear inclusions in reticuloendothelial cells of the spleen or intestine. Vaccines using avirulent HEV strains provide control of the

1. HEMORRHAGIC
ENTERITIS OF TURKEYS
DEFINITION
Hemorrhagic enteritis (HE) is a
viral disease of young
turkeys characterized by sudden
onset, depression,
bloody droppings, and variable but
often high mortality.
A subclinical form characterized by
an enlarged, mottled
spleen occurs and is more
common than the acute form

2. • OCCURRENCE
• HE has a worldwide distribution and typically occurs
in 6-12-week-old turkeys, but has been seen in
poults as young as 2 weeks.
• It is rare in turkeys less than 4 weeks
• of age, presumably because of maternal antibody.

3. history
HE in turkeys was first reported in 1937
In 1972 the disease
was demonstrated to be caused by a
viral infection.
ETIOLOGY
HE is caused by a turkey
adenovirus, hemorrhagic enteritis
virus.

4. EPIZOOTIOLOGY
1. The virus is very resistant to
environmental factors and
is shed in feces, hence the
transmission route is fecal-
oral. Infection frequently reoccurs
on the same farm in
successive flocks.
2. There is no evidence of egg
transmission.
3. Infection of turkeys with HE
virus results in a transient
immunosuppression, often
involving secondary
colibacillosis.

5. CLINICAL SIGNS
1. Sudden deaths are often the
first sign of HE in a flock.
A concurrent drop in feed and
water consumption may
be noted. Droppings
containing fresh blood or
melena
can be seen, especially around
waterers.

6. Blood may be seen oozing from the
vent of dead or moribund birds or
may be adhered to
feathers around the vent. Blood
may be expelled from
the vent if the abdomen is
squeezed.
Most birds with bloody feces die.

7. The disease usually runs its course
in a flock in 10-14 days.
Most mortality occurs
over a 10 day period.
Mortality averages 5-10% but may
exceed 60%

8. Outbreaks of coli septicemia often
follow clinical and
subclinical infections with
hemorrhagic enteritis virus
12 to14 days later. Coli septicemia
may be the only
indication of prior HE subclinical
infection.

9. LESIONS
Dead poults often appear pale due
to intestinal blood
loss but are well fleshed with feed
in their crops. The skin and feathers
around the vent can be stained with
blood or blood stained feces.

10. duodenal loop, is
distended, dark purple, and filled
with hemorrhagic
content The intestinal mucosa,
especially of the duodenum is
congested, and may be covered
with a yellow layer of fibrin
necrotic exudates.

11. the spleen is
typically very enlarged and mottled
(Fig. 2) and as the disease
progresses, the spleen becomes
smaller and pale.

12. Microscopically, early in the course of the
disease,
reticuloendothelial cells of the spleen
contain
numerous large intranuclear adenoviral
inclusions
and the condensed nuclear chromatin
around the
inclusions often resembles a signet ring

13. DIAGNOSIS
1. Typical history and gross lesions
strongly suggest the
diagnosis. Demonstration of
intranuclear inclusions
in reticuloendothelial cells in the
spleen or intestine
confirms the diagnosis unless the
turkeys have
received HE vaccine.

14. The disease can be reproduced in
6-week-old or older,
susceptible poults by giving minced
splenic tissue or
its supinate intravenously, orally, or
interlocally.
Typical intestinal content also will
reproduce the
disease when given orally or
cloacal.

15. it is possible to use the
agar-gel diffusion test to
demonstrate antigen in the
spleen of an infected turkey or
to demonstrate antibody
in the convalescent sera of
recovered birds.

16. HE must be differentiated from
acute bacterial
septicemia including coli
septicemia, salmonellosis, fowl
cholera and erysipelas.
Gastrointestinal hemorrhage/
mucosal congestion may be
associated with acute
septicemic/viremic/bacteremia
conditions.

17. CONTROL
1. Avirulent strains of HEV and
related marble spleen
disease (of pheasants) virus are
used as vaccines.
2. Vaccines are prepared as crude
splenic homogenates
or are cell culture derived.

18. Intestinal
coccidiosis should also be
considered. HEV infection
in growing turkeys results in
immunosuppression
predisposing birds to secondary
infections such as
Escherichia coli septicemia