Author, Donkey, Bureaucrats, Administrators
53,803
edits
Changes
Jump to navigation
Jump to search
no edit summary
Also known as: '''''BAdV'''''
== Introduction ==
== Introduction ==
Bovine Adenovirus belong to the [[Adenoviridae]] family.
Bovine Adenovirus belong to the [[Adenoviridae]] family.
Most adenovirus infections in cattle involve either the '''[[Respiratory system|respiratory] (e.g. [[Rhinitis#Infectious causes of rhinitis|rhinitis]]) or [Alimentary system|gastrointestinal] tracts'''. In addition there have been reports of adenovirus associated with '''conjunctivitis, keratoconjunctivitis, and weak calf syndrome'''. It is now also thought to contribute to the disease complex '''[[Enzootic Pneumonia - Calves|Enzootic pneumonia of calves]]'''. Bovine adenoviruses have also been isolated from healthy cattle.
Most adenovirus infections in cattle involve either the '''respiratory (e.g. [[Rhinitis|rhinitis]]) or gastrointestinal tracts'''. In addition there have been reports of adenovirus associated with '''conjunctivitis, keratoconjunctivitis, and weak calf syndrome'''. It is now also thought to contribute to the disease complex '''[[Enzootic Pneumonia - Calves|Enzootic pneumonia of calves]]'''. Bovine adenoviruses have also been isolated from healthy cattle.
Currently there are '''10 recognised serotypes''' of adenovirus in cattle<ref> Benko, M., Harrach, B., Russell, W. C (2000) '''Family Adenoviridae'''. In: Van Regenmortel, M. H. V., Fauquet, C. M., Bishop, D. H. L., Carstens, E. B., Estes, M. K., Lemon, S. M., Maniloff, J., Mayo, M. A., McGeoch, D. J., Pringle, C. R., Wickner, R. B. eds. '''Virus Taxonomy'''. Seventh Report of the International Committee on Taxonomy of Viruses. ''New York, San Diego, USA: Academic Press'', 227-238</ref>
Currently there are '''10 recognised serotypes''' of adenovirus in cattle<ref> Benko, M., Harrach, B., Russell, W. C (2000) '''Family Adenoviridae'''. In: Van Regenmortel, M. H. V., Fauquet, C. M., Bishop, D. H. L., Carstens, E. B., Estes, M. K., Lemon, S. M., Maniloff, J., Mayo, M. A., McGeoch, D. J., Pringle, C. R., Wickner, R. B. eds. '''Virus Taxonomy'''. Seventh Report of the International Committee on Taxonomy of Viruses. ''New York, San Diego, USA: Academic Press'', 227-238</ref>
The respiratory and enteric tracts are the primary targets for adenovirus infection which usually results in '''cell lysis and virus shedding''', but some cells accumulate virus particles in the nucleus establishing '''persistent infections.'''
The respiratory and enteric tracts are the primary targets for adenovirus infection which usually results in '''cell lysis and virus shedding''', but some cells accumulate virus particles in the nucleus establishing '''persistent infections.'''
Respiratory and '''faecal shedding''' usually last for about 10 days and, where the kidney is involved, virus can be excreted for over 10 weeks in '''urine'''.<ref>Áldásy, P., Rusvai, M., Bartha, A (1965) Pneumo-enteritis in calves caused by adenoviruses. Acta Veterinaria Academiae Scientiarum Hungaricae, 15:167-175.</ref> With persistent infection, lysis of fragile infected cells produces virus-shedding resulting in infection of susceptible animals that come in contact with the virus.
Respiratory and '''faecal shedding''' usually last for about 10 days and, where the kidney is involved, virus can be excreted for over 10 weeks in '''urine'''.<ref>Áldásy, P., Rusvai, M., Bartha, A (1965) '''Pneumo-enteritis in calves caused by adenoviruses. '''''Acta Veterinaria Academiae Scientiarum Hungaricae,'' 15:167-175.</ref> With persistent infection, lysis of fragile infected cells produces virus-shedding resulting in infection of susceptible animals that come in contact with the virus.
== Signalment ==
== Signalment ==
Bovine Adenovirus can infect cattle and zebu of any breed, sex or age, however, younger animals are more at risk as their maternal antibody begins to wane, around the age of '''2 weeks to 4 months old'''. Experimentally, the virus has also been shown to infect goats and sheep.
Bovine Adenovirus can infect cattle and zebu of any breed, sex or age, however, younger animals are more at risk as their maternal antibody begins to wane, around the age of '''2 weeks to 4 months old'''. Experimentally, the virus has also been shown to infect goats and sheep.
== Clinical Signs ==
== Clinical Signs ==
Because adenoviruses can be isolated from apparently healthy cattle, isolation of adenoviruses from clinically sick calves does not necessarily mean that the isolated adenovirus type plays an aetiological role in the clinical disease. For adenovirus to be considered as the aetiologic agent in a particular disease, the '''antibody titre should be low at the onset of the infection and result in at least a four-fold increase in neutralizing antibodies'''.
Because adenoviruses can be isolated from apparently healthy cattle, isolation of adenoviruses from clinically sick calves does not necessarily mean that the isolated adenovirus type plays an aetiological role in the clinical disease. For adenovirus to be considered as the aetiologic agent in a particular disease, the '''antibody titre should be low at the onset of the infection and result in at least a four-fold increase in neutralizing antibodies'''.
Adenovirus infection can be diagnosed morphometrically, serologically, and by virus isolation. Rapid presumptive diagnosis can be made either by observation of characteristic virus morphology in '''intranuclear inclusions by transmission electron microscopy or by immunofluorescent or immunohistochemical labelling''' of adenovirus antigens in tissues with gross lesions.
Adenovirus infection can be diagnosed morphometrically, serologically, and by virus isolation. Rapid presumptive diagnosis can be made either by observation of characteristic virus morphology in '''intranuclear inclusions by transmission electron microscopy or by [[Immunofluorescence|immunofluorescent]] or immunohistochemical labelling''' of adenovirus antigens in tissues with gross lesions.
Because of the number of types of adenoviruses infecting cattle, virus isolation is necessary to definitively identify the virus. Virus can be '''isolated from nasal secretions, tracheal fluids, intestinal contents and tissue homogenates.'''
Because of the number of types of adenoviruses infecting cattle, virus isolation is necessary to definitively identify the virus. Virus can be '''isolated from nasal secretions, tracheal fluids, intestinal contents and tissue homogenates.'''
== References ==
== References ==
Baber, D. J., Candy, J. B (1981) '''Isolation and characterization of bovine adenoviruses types 3, 4 and 8 from free living African buffaloes (Syncerus caffer)'''. Research in Veterinary Science, 31(1):69-75.
Baber, D. J., Candy, J. B (1981) '''Isolation and characterization of bovine adenoviruses types 3, 4 and 8 from free living African buffaloes (Syncerus caffer)'''. ''Research in Veterinary Science'', 31(1):69-75.
Belák, S., Palfi, V (1974) '''An adenovirus isolated from sheep and its relationship to type 2 bovine adenovirus'''. ''Archiv für die gesamte Virusforschung'', 46(3-4):366-369.
Benkö, M., Bartha, A., Möstl, K., Bürki, F (1989) '''A heteroploid permanent cell line originating from embryonic calf thyroid supporting the replication of all known bovine adenovirus serotypes.''' ''Veterinary Microbiology'', 19(4):317-324; 10
Boros, G., Graf, Z., Benkö, M., Bartha, A (1985) '''Isolation of a bovine adenovirus from fallow deer (''Dama dama'')'''. ''Acta Veterinaria Hungracia'', 33(1-2):119-123.
Davies, D. H., Humphreys, S (1977) '''Characterization of two strains of adenovirus isolated from New Zealand Sheep'''. ''Veterinary Microbiology'', 2:97-107.
{{review}}
{{review}}
[[Category:Adenoviridae]][[Category:Cattle Viruses]][[Category:Respiratory Diseases - Cattle]][[Category:Intestinal Diseases - Cattle]]
[[Category:Adenoviridae]][[Category:Cattle Viruses]][[Category:Respiratory Diseases - Cattle]][[Category:Intestinal Diseases - Cattle]]
[[Category:To Do - CABI review]]
[[Category:CABI Expert Review]]
[[Category:Respiratory_Viral_Infections]]
[[Category:Respiratory_Viral_Infections]]