bornaviridae, astroviridae, birnaviridae Flashcards Preview

VIRO final > bornaviridae, astroviridae, birnaviridae > Flashcards

Flashcards in bornaviridae, astroviridae, birnaviridae Deck (16):


oral nasal route, persistent infection of neurons usually fatal mostly in horses and sheep of Europe, transmission of BDV not clear


bornaviridae path

virus pass intra-axonally to the olfactory bulbs of the brain from olfactory nerve endings, virus disseminates throughout the CNS, virus replicates in neurons and glial cells causes severe encephalomyelitis
distinctive eosinophilic Joest Degen Bodies in neurons


borna disease clinical signs

dysfunctions in the limbic system, later stages can cause dysfunctions of the motor systems causing paralysis, and paresis
surviving horses may have sensory or mortar defecits


astroviridae general

five or six point stars, genome singular linear +ssRNA


astrovirus enteritis

mild, self limiting enteritis
transmission fecal oral
in calves, lambs, puppies, kittens, piglets, humans


clinical signs astroviridae enteritis

diarrhea, dehydration. vomiting, abdominal pain


pathogensis calves astroviridae

virus destroys dome M cells and absorptive enterocytes, resulting in watery diarrhea


pathogenesis lambs astroviridae

mature enterocytes of villi are affected, causing stunting and fusion


genus- avibirnavirus
DZ- infectious burial disease virus IBDV

acute highly contagious, viral infection of young chickens, predilection for the bursa where B cell form


birnaviridae general

non enveloped, hexagonal, single shell icosahedral, two segments linear dsRNA, virus replication in cytoplasm


IBDV 2 serotypes

2= asymptomatic
1= 3 antigenic, one is very virulent (50-100%)


IBDV transmission

stable in nature, can survive in poultry houses even after cleaned, can be in water


IBDV pathogenesis

immunosuppression-in recovered birds or subclinical cases, diminished Anitbody response and increased susceptibility to a wide range of opportunistic infectious agents, maximum virus replication in bursa and depletion of b cells due to both necrosis and apoptosis


IBDV signs

distress, depression, ruffled feathers, diarrhea, anorexia, dehydration, swollen bursa fabrics with hemorrhages, atrophied bursa, SC hemmorhage, his to shows atrophy of bursa


IBDV prevention

attenuated vaccine with mild, intermediate and intermediate plus.
mild vaccines that cause no bursal lesions cannot be used in chicks with maternal antibodies, intermediate can be given with maternal antibodies though


IBDV vaccine

have a live recombinant vaccine that uses a viral vector (herpes virus of turkeys) to express the VP2 antigen of IBDV in chickens is recent