Circoviridae Flashcards
What two infections does Circovirus cause?
- Porcine circovirus type-1 (non-path)
2. Porcine circovirus type-2 (PMWS)
What infection does gyrovirus cause?
Chicken infectious anemia
T/F: circovirus and gyrovirus both have circular, single stranded DNA, but circrovirus has ambisense DNA and gyrovirus has negative sense DNA
True
T/F: For circoviridae, virus replication occurs in non active cell
False, occurs in actively dividing cell
What cell structure does DNA replication occur for circoviridae?
Nucleus
Who is most commonly affects by PMWS caused by porcine circovirus 2 (PCV2)?
Pigs at 4-6 or 2-3 weeks post-weaning
What is the most common method of spread for PMWS caused by PCV2?
Fecal-oral transmission
T/F: Horizontal transmission occurs in swine with PMWS caused by PCV2
False, vertical transmission (transplacental infection)
How is PMWS caused by PCV2 distinctly characterized histologically?
Botryoid inclusion bodies in macrophages
Lymphoid depletion caused by PMWS causes a loss of what two types of cells?
B and T cells
T/F: subclinical infections are the most common CS of PMWS
True
T/F: PMWS can be severe with more pronounced lesions if there is a co-infection with other viruses
True
Is antigen detection for PMWS effective?
No, because most pigs are seropositive
What are 2 vaccinations for PMWS?
- Chimeric vaccine
2. Inactivated or baculoviruse-expressed vaccines
When are sows vaccinated for PMWS?
2 and 5 weeks antepartum
Porcine dermatitis and nephropathy syndrome (PDNS) is associated with what porcine virus?
PCV2
Who is primary affected by chicken infectious anemia caused by PCV2?
Young chickens (2-4 weeks age)
What are 3 transmission routes of chicken infectious anemia?
- Shed in feces and feather dander
- Horizontal via inhalation and oral route
- Vertically via egg
T/F: The principal sites of replication for chicken infectious anemia are hemocytoblasts in bone marrow, precursor T cells in cortex of thymus, and dividing CD4 and CD8 cells in spleen
True
What is the main Dx method for chicken infectious anemia?
Examination of blood: low PCV, watery blood, slow clotting
