Porcine
Epidemic Diarrhoea
Causal agent |
Porcine Epidemic
Diarrhoea Virus a Coronavirus - RNA virus |
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The virus
particles are called corona because of their appearance of a sun with the
surrounding corona |
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Other names |
PEDV |
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Age group |
Type 1 affects
all age groups but not suckling piglets Type 2 affects
all age groups, clinical signs particularly severe in naive piglets but is
not TGE virus – another coronavirus. The disease is
reported in Europe and Asia but not in the America’s or Australia |
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Clinical signs
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Acute Naive
herd |
Explosive
outbreak similar to TGE |
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Mortality of piglets may reach 80% |
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Acute watery
diarrhoea in piglets |
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Diarrhoea and
vomiting may be seen in all age groups |
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Problems persist
for 4-6 weeks |
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The condition
can occur at any time but is more severe in the winter |
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Endemic herd |
Little or no
problem virus progressively dies out |
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Disease may be
more persistent than TGE |
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Piglets with PEDV |
Sow diarrhoea with PED |
Dilated small intestine |
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Incubation period |
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Pathological
findings can be seen in 12 hours. Infection can take up to 5 days |
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Transmission
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Transmission is
via the faecal oral route |
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Role of formites
is very important |
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Mechanism of
persistence is not known |
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Post-mortem Lesions |
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Lesions are
mainly in the jejunum and ileum. The duodenum is less affected. The lesions are villus atrophy. The pH of the intestine changes to
acidic. In Esherichia coli infections the pH becomes more alkaline |
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Diagnosis |
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The virus is
distinct from TGE and PRC |
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Immunohistochemistry
of the infected intestines |
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Antibody tests useful,
but virus and antibodies may be present without clinical signs |
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Treatment and control |
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Treatment |
No specific
treatment |
Provide
supportive electrolytes for affected piglets.
Piglets may require supportive therapy for 2 weeks, until intestinal
tract heals |
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Ensure all
piglets get colostrum |
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As the virus
does not spread rapidly around the farm, attempt to isolate the next 3 weeks
worth of farrowing sows |
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In an outbreak |
Feedback
farrowing house diarrhoea and gut materials from infected piglets to sows
from breeding to 3 weeks pre-farrowing.
Ensure gilts in isolation receive this material as well |
Stop introduction
of new animals into the herd for 6 weeks |
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Control |
Ensure gilts
receive feed back |
Good biosecurity
and practice all-in/all-out |
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Purchase gilts
and boars from known negative herds |
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Common differentials |
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Transmissible
Gastroenteritis. Salmonellosis |