Viral Diseases of Ruminants II (13) Flashcards
What class is bovine viral diarrhea classified as?
flaviviruses
genus pestivirus
What are properties of flaviviruses?
unstable in environment
wide range of systemic clinical presentations most importantly encephalitis
many serotypes
diagnosis ELISA, PCR, virus isolation
transmission by arthropods and direct contact (pestiviruses)
What is BVD? It is classified as a _____ disease
spreads by contact and most secretions/excretions contain virus
vaccines widely used
respiratory
T/F: There is no vaccine for BVD
false - widely used
These oral lesions are common in what disease?
BVD
What are clinical signs of BVD?
acute infection
usually subclinical
diarrhea
depression
oculonasal discharge
anorexia
decreased milk production
oral ulceration
pyrexia
leukopenia
respiratory
Gut lesions in BVD/mucosal disease involves depletion of ______ and _______
Peyer’s patch
ulcerations
How is BVD transmitted?
vertical and horizontal transmission
What does transiently infected with BVD mean?
typically adult animals
infection lasts 10-14 days - animals become less productive
shed relatively low amounts of the virus
animals develop long-standing immunity after they recover
What does persistently infected with BVD mean?
calves born to dams that became infected at 30-110 days of pregnancy
infection lasts for life
- some will be poor-doers and self-cull
- some will appear healthy
shed high amounts of the virus for their entire life
T/F: An abortion can occur with those infected with BVD
TRUE
T/F: A non-vaccinated or immunocompromised cattle can become infected when exposed to a PI calf (70-100%)
TRUE
Define congenital BVD symptoms
mainly neurologic
cerebellar hypoplasia
spastic or dummy calf
cataracts, poor doers, microphthalmia
Some persistently infected animals of BVD [will/will not] give birth to a PI calf
will
When are BVD vaccines useful?
before pregnancy
detecting and culling persistently infected calves is important to control disease in the herd
Bovine respiratory disease complex is also called _____
shipping fever
What is the most common and costly disease affecting NA beef industry?
bovine respiratory disease complex
What does bovine respiratory disease complex incorporate?
a combination of a suppressed immune system with overgrowth of bacteria from the upper respiratory tract moving to the lower respiratory tract
Bacteria of BRDC cause ______, and settle out in the cranial-ventral lung
bronchopneumonia
What is the pathogenesis of BRDC?
What are the most common viruses associated with BRDC?
What are the most common bacteria associated with BRDC?
How do you recognize BRD?
How do you control and prevent BVD?
avoid mixing cattle from multiple sources
minimize transport times
avoid stacking stressful events
herds should have vaccine protocol
consider metaphylaxis (treatment of group of animal without signs of disease)
