bornaviridae, astroviridae, birnaviridae

Question 1

bornaviridae

Answer 1

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

Question 2

bornaviridae path

Answer 2

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

Question 3

borna disease clinical signs

Answer 3

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

Question 4

astroviridae general

Answer 4

five or six point stars, genome singular linear +ssRNA

Question 5

astrovirus enteritis

Answer 5

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

Question 6

clinical signs astroviridae enteritis

Answer 6

diarrhea, dehydration. vomiting, abdominal pain

Question 7

pathogensis calves astroviridae

Answer 7

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

Question 8

pathogenesis lambs astroviridae

Answer 8

mature enterocytes of villi are affected, causing stunting and fusion

Question 9

birnaviridae
genus- avibirnavirus
DZ- infectious burial disease virus IBDV

Answer 9

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

Question 10

birnaviridae general

Answer 10

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

Question 11

IBDV 2 serotypes

Answer 11

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

Question 12

IBDV transmission

Answer 12

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

Question 13

IBDV pathogenesis

Answer 13

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

Question 14

IBDV signs

Answer 14

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

Question 15

IBDV prevention

Answer 15

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

Question 16

IBDV vaccine

Answer 16

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