Bovine Viral Diarrhea Flashcards
what viral family does BVD belong to
flaviviridae
what type of virus is BVD
RNA
enveloped
what are the 2 types of BVD
cytopathic
noncytopathiic
where does non-cytopathic BVD replicate
leukocytes
lymphoid tissue
proximal colon
respiratory tract
where does cytopathic BVD replicate
gastrointestinal tract
where can BVDV replicate in persistently infected intact males
seminal vesicles and prostate gland
is there more of a concern with intact males being persistenly infected
yes because they can now transmit the diease venerally
where is the primary replication site of BVD
tonsils
nasal mucosa
where do the high virulent strains spread to
T-cell dependent areas
bone marrow
true or false
there is persistent viremia with non-cytopathic BVD
true
what is dangerous about the spread of a non-cytopathic BVD
transplacental and intrauterine passing of the virus leads to persistently infected calves from birth
what are the clinical signs in a post natal infection of a non-pregnant cow
panleukopenia / immunosuppression
infection is trivial
diarrhea
nasal and ocular discharge
erosive stomatitis
drop in milk yeild
what are the clinical signs seen in an infected pregnant cow
transplacental spread
early infection = reabsorption of fetus
80-125 days = immunotolerant to BVD / persistently infected
after 125 days = abortions, weak calf syndrome, congenital defects
what are the most common clinical signs in a calf infected after 125 days in the womb
CNS
cerebellar hypoplasia
ataxia
tremors
wide stance
stumbling
death
how can calves infected between the days of 80-125 in utero present
1 - superinfection with homologous BVD
2 - mutatioin of the ncp to cytopathic variant
3 - vaccination with attenuated BVD