Circoviridae

Question 1

What are the 2 genus that fall under Circoviridae?

Answer 1

1. Circovirus

2. Gyrovirus

Question 2

3 diseases caused by Circoviruses

Answer 2

1. Psittacine beak and feather disease
2. Porcine Circovirus type-1
3. PCV-2 (PMWS)

Question 3

1 disease caused by Gyroviruses

Answer 3

Chicken infectious anemia virus

Question 4

T/F Viruses belonging to Circoviridae are large, almost the size of Poxviruses.

Answer 4

False, size is 17-22 nm

Question 5

What type of symmetry does the family circoviridae have? Enveloped?

Answer 5

Spherical, icosohedral.

Non-enveloped

Question 6

What type of DNA does Circoviridae contain?

Answer 6

Circular single-stranded DNA.

Question 7

What DNA sense do circoviruses have? Gyroviruses?

Answer 7

Circoviruses- ambisense

Gyroviruses- Negative sense

Question 8

What is significant about Chicken Infectious Anemia Virus structure compared to other viruses in Circoviridae?

Answer 8

12 trumpet like structures

Question 9

Where do Circoviridae viruses replicate?

Answer 9

In the nucleus of a cell (actively dividing cell)

Question 10

What is the most common route of transmission of Post-Weaning Multisystemic Wasting Syndrome in pigs?

Answer 10

Fecal-oral

Question 11

Can PMWS be vertically transmitted?

Answer 11

yes, transplacentally

Question 12

Is Circoviridae stable in the environment?

Answer 12

yes

Question 13

Concerning PMWS where would you see “botryoid bodies” during histology?

Answer 13

Macrophages

Question 14

what pathogenesis is consistently seen in the blood of pigs infected with PMWS?

Answer 14

Lymphopenia- however this loss of lymphocytes is not well understood

Question 15

What happens if transplacental infection with PMWS occurs in the 1st or 2nd trimester?

Answer 15

Resorption or abortion of fetus

Question 16

Clinical Signs of PMWS

Answer 16

Lethargy
Progressive weight loss
Cough
Dyspnoea
Stunted growth
Lymphadenopathy
Diarrhea
Skin Discoloration
Congenital tremors
Possibly icterus

Question 17

A pig with PMWS is also infected with Mycoplasma hyopneumoniae. What disease would you expect to see?

Answer 17

Chronic bronchopneumonia

Question 18

When would you give the following PCV-1 or PCV-2 vaccinations:
1st piglet dose
2nd piglet dose
Sow dose

Answer 18

1st- 3 weeks
2nd- 6weeks
Sow- 2-5weeks antepartum

Question 19

What disease, other than PMWS, is associated with PCV-2?

Answer 19

Porcine Dermatitis and Nephropathy Syndrome

PDNS

Question 20

PDNS is reported in what age group of pigs?

Answer 20

Older piglets

Question 21

Chicken Anemia Virus causes what disease in chickens?

Answer 21

Chicken infectious Anemia

Question 22

What age group is CAV highly contagious to?

Answer 22

Chicks 2-4 wks old

Question 23

How is CAV transmitted?

Answer 23

Shed in feces and dander- inhaled or oral exposure

vertically

Question 24

Which cells is CAV replicated in causing anemia and immunosuppression?

Answer 24

hemocytoblasts

Tcells

Question 25

What is the protein associated with CAV induced apoptosis of replicating cells?

Answer 25

Apoptin

Question 26

Clinical signs of Chicken Infectious Anemia

Answer 26

Anorexia
Lethargy
Depression
reduced weight gain
Low PCV
Watery blood with low clotting ability
SubQ hemorrhages
Skeletal hemorrhages

Question 27

What happens to the thymus of chickens infected with CAV?

Answer 27

Atrophy

Question 28

Concerning vaccination protocols for chickens, what other disease should be controlled due to the synergistic immunosuppressive factors?

Answer 28

Marek’s disease