هم فيروسات الطيور المائيةduck diseases

أهم فيروسات الطيور المائيةduck diseases

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Duck Virus hepatitis[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]
Duck virus hepatitis is a highly fatal contagious disease of young
ducklings, 1-28 days of age. Ducklings are most susceptible at the
younger ages and gradually become more resistant as they grow older. The
disease is rarely seen in ducklings over 4 weeks of age. The onset of
the disease is very rapid, it spreads quickly through the flock and may
cause up to 90% mortality. Sick ducklings develop spasmodic contractions
of their legs and die within an hour in a typical "arched-backward"
position. The liver is enlarged and shows hemorrhagic spots. To prevent
this disease, keep age groups isolated and vaccinate breeder ducks with
an attenuated live virus duck hepatitis vaccine (to produce maternally
immune ducklings).
Duck Plague (Duck Virus Enteritis)
Duck virus enteritis is an acute, contagious, highly fatal disease of
waterfowl caused by a herpes virus. This disease is most likely to
affect mature ducks, but is also seen in young ducks. Affected birds
show sluggishness, ruffled feathers, greenish-yellow diarrhea that is
sometime blood-stained. Dead birds often have blood-stained feathers
around the vent and blood dripping from the nostrils. Hemorrhages may be
found in tissues throughout the body. Eruptive lesions of the mucous
lining of the esophagus and intestine are characteristic signs of the
disease. Necrotic plaques may be observed in the cloaca. Regular
immunization of breeder ducks with an attenuated live duck virus
enteritis vaccine provides adequate protection