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| + | {{OpenPagesTop}} |
| + | {{Podcasts |
| + | |link = https://bloomsbury.mediacore.tv/podcasts/wikivet-english/duck-hepatitis-virus}} |
| {{Taxobox | | {{Taxobox |
| |name = DHV-II | | |name = DHV-II |
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| |sub-order = | | |sub-order = |
| |super-family = | | |super-family = |
− | |family = Astroviridae | + | |family = [[:Category:Astroviridae|Astroviridae]] |
| |sub-family = | | |sub-family = |
| |genus = Astrovirus | | |genus = Astrovirus |
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| Also Known As: '''''Duck Viral Hepatitis''''' — '''''DVH''''' — '''''DH''''' | | Also Known As: '''''Duck Viral Hepatitis''''' — '''''DVH''''' — '''''DH''''' |
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− | Caused By: '''''Duck Hepatitis Virus 1 and 3'' — ''DHV-I'' — ''DHV-III'' | + | Caused By: '''''Duck Hepatitis Virus 1 and 3'' — ''DHV-1'' — ''DHV-3'' |
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| ==Introduction== | | ==Introduction== |
− | Duck hepatitis is caused by the [[:Category:Enteroviruses|'''enteroviruses''']] DHV-I and DHV-III. | + | Duck hepatitis is caused by the [[:Category:Enteroviruses|'''enteroviruses''']] DHV-1 and DHV-3. |
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| It is a '''highly fatal''' disease of ducklings causing very high '''mortality''', '''opisthotonus''' and '''hepatitis'''. | | It is a '''highly fatal''' disease of ducklings causing very high '''mortality''', '''opisthotonus''' and '''hepatitis'''. |
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− | The disease is '''notifiable''' to the World Organisation for Animal Health [http://www.oie.int/ (OIE)]
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| ==Signalment== | | ==Signalment== |
| Ducks are the only species naturally affected. | | Ducks are the only species naturally affected. |
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− | DHV-I occurs only in '''young ducklings''', usually '''<6 weeks''' of age and spreads rapidly within a flock. It is the '''most virulent''' of the three. | + | DHV-1 occurs only in '''young ducklings''', usually '''<6 weeks''' of age and spreads rapidly within a flock. It is the '''most virulent''' of the three. |
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− | DHV-II is only reported in outdoor ducks on open fields. | + | DHV-2, an astrovirus (duck astrovirus 1), not an enterovirus, has only been reported in outdoor ducks on open fields. |
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| Duck Hepatitis is not considered zoonotic. | | Duck Hepatitis is not considered zoonotic. |
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| ==Distribution== | | ==Distribution== |
− | DHV-I is present worldwide. | + | DHV-1 is present worldwide. |
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− | DHV-II has only been reported in Norfolk, England <ref> Asplin, F. D. (1965) '''Duck hepatitis: vaccination against two serological types. '''''Vet. Rec.'', 77:1529-1530</ref> and no outbreaks have been recorded since the 1980’s.
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− | DHV-III has only occurred in the USA. | + | DHV-2 has only been reported in Norfolk, England and no outbreaks have been recorded since the 1980’s. |
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− | The '''rat''' acts as a vector for Duck Hepatitis.
| + | DHV-3 has only been reported in the USA. |
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| ==Clinical Signs== | | ==Clinical Signs== |
| '''Sudden deaths, Opisthotonus, Paresis''', Paralysis, Enopthalmos. | | '''Sudden deaths, Opisthotonus, Paresis''', Paralysis, Enopthalmos. |
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− | DHV-I infection is most virulent. Death usually occurs within 1-2 hours of clinical signs. | + | DHV-1 infection is most virulent. Morbidity is 100%, with mortality <95% up to one week of age, <50% for 1-3 weeks of age and negligible thereafter. Death usually occurs within 1-2 hours of clinical signs. |
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− | Mortality rates are lower in DHV-II infections, reaching only 20%. | + | Mortality rates are lower in DHV-2 infections, reaching only 20%. |
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| ==Diagnosis== | | ==Diagnosis== |
| On post-mortem examination, the '''[[Avian Liver - Anatomy & Physiology|liver]]''' is '''enlarged''', appears '''greenish''' and displays distinct '''ecchymotic haemorrhages'''. | | On post-mortem examination, the '''[[Avian Liver - Anatomy & Physiology|liver]]''' is '''enlarged''', appears '''greenish''' and displays distinct '''ecchymotic haemorrhages'''. |
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− | Splenic and [[Exotic Urinary System - Anatomy & Physiology#Avian||kidney]] swelling may also be evident. Cutaneous haemorrhage is often noted. | + | Splenic and [[Exotic Urinary System - Anatomy & Physiology#Avian|kidney]] swelling may also be evident. Cutaneous haemorrhage is often noted. |
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| On histopathology, '''necrosis''' and inflammatory infiltrate are visible within hepatic cells. | | On histopathology, '''necrosis''' and inflammatory infiltrate are visible within hepatic cells. |
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− | '''Innoculation''' from liver suspensions can be used for confirmation of all DHVs. | + | '''Innoculation''' from liver suspensions can be used for confirmation of all DHVs using embryonated duck eggs, chicken eggs and tissue culture. |
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− | '''Direct [[immunofluorescence]]''' can also confirm presence of DHV-I. | + | '''Direct [[immunofluorescence]]''' can also confirm presence of DHV-1. |
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| '''Virus Neutralisation (VN)''' serological tests can be used to monitor vaccination response and epidemiology. | | '''Virus Neutralisation (VN)''' serological tests can be used to monitor vaccination response and epidemiology. |
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| ==Control== | | ==Control== |
− | '''Vaccination''' is only commercially available against '''DHV-I'''. Immunisation involves two or three innoculations. Live, live attenuated and inactivated forms are available. | + | '''Vaccination''' is only commercially available against '''DHV-1'''. Immunisation involves two or three innoculations. Live, attenuated and inactivated forms are available. |
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− | DHV-I can be prevented by '''strict isolation''' in the first 4-5 weeks of life. | + | DHV-1 can be prevented by '''strict isolation''' in the first 4-5 weeks of life. |
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| The viruses are resistant to inactivation by heat, acid and some disinfectants. Only 5% phenol and formaldehyde are successful in inactivating the viruses. | | The viruses are resistant to inactivation by heat, acid and some disinfectants. Only 5% phenol and formaldehyde are successful in inactivating the viruses. |
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| ==References== | | ==References== |
− | <references/>
| + | Gough R.E. and McNulty, M.S. (2007) '''Picornaviridae'''. In: '''Poultry Diseases, 6th Edition''' (eds. Pattison, M., McMullin, P., Bradbury, J., Alexander, D.) ''Saunders, Elsevier'', pp 350-359 |
− | Animal Health & Production Compendium, '''Duck Hepatitis Virus datasheet''', accessed 05/06/2011 @ http://www.cabi.org/ahpc/
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| + | Woolcock, P.R. (2008) '''Duck Hepatitis'''. In: '''Diseases of Poultry, 12th Edition''' (eds. Saif, Y.M., Fadly A.M., Glissen J.R., McDougald L.R., Nolan L.K., Swayne D.E.) ''Wiley-Blackwell'', pp 373-384 |
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| + | {{CABI source |
| + | |datasheet = [http://www.cabi.org/ahpc/?compid=3&dsid=84184&loadmodule=datasheet&page=2144&site=160 duck hepatitis], [http://www.cabi.org/ahpc/Default.aspx?site=160&page=2144&LoadModule=datasheet&CompID=3&dsID=84185 duck hepatitis virus] and [http://www.cabi.org/ahpc/Default.aspx?site=160&page=2144&LoadModule=datasheet&CompID=3&dsID=84186 duck hepatitis virus type II] |
| + | |date =5 June 2011 |
| + | }} |
| + | <br><br> |
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| + | {{Dave Cavanagh |
| + | |date = 23 August 2011 |
| + | }} |
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| + | {{OpenPages}} |
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− | {{review}}
| + | [[Category:CABI Expert Review Completed]][[Category:CABI AHPC Pages]] |
− | [[Category:CABI Expert Review]] | |
| [[Category:Enteroviruses]] | | [[Category:Enteroviruses]] |
| + | [[Category:Astroviridae]] |
| [[Category:Avian Viruses]] | | [[Category:Avian Viruses]] |
| [[Category:Alimentary Diseases - Birds]] | | [[Category:Alimentary Diseases - Birds]] |
| [[Category:Neurological Diseases - Birds]] | | [[Category:Neurological Diseases - Birds]] |