Circoviridae

Question 1

What are the 2 genuses in family Circovridae?

Answer 1

• Circovirus*
• Gyrovirus*

Question 2

Chicken infectious anemia is part of genus _________

Answer 2

Gyrovirus

Question 3

Which disease of genus circovirus affects birds?

Answer 3

Psittacine beak and feather disease virus

Question 4

Which porcine virus is non-pathogenic?

Answer 4

Porcine circovirus Type 1

Question 5

*Porcine circovirus type 2 *is also known as

Answer 5

PMWS (Post-weaning Multisystemic Wasting Syndrome)

Question 6

Describe the DNA of family Circoviridae

Answer 6

circular SSDNA

Question 7

Both genuses *Circovirus *and Gyrovirus have circular SSDNA, but one is

negative sense SSDNA

and one is

ambisense SSDNA

Answer 7

• Circovirus -ambisense*
• Gyrovirus- negative sense*

Question 8

**Trumpet-like structures **are seen on the surface of which genus of Circoviridae?

Answer 8

Gyrovirus (Chicken Infectious Anemia)

Question 9

Circoviruses are small, non-enveloped, spherical viruses with

________ symmetry

Answer 9

Icosahedral symmetry

Question 10

Circoviruses replicate in actively dividing cells, but replication of their circular SSDNA occurs in the ________

Answer 10

nucleus

Question 11

PMWS or Porcine circovirus Type 2

is found in all secretions and _________ transmission is the most common route

Answer 11

fecal-oral

Question 12

PMWS (Porcine circovirus 2)

can occur via the transplacental route as well as fecal-oral route which is the most common.

What happens to the fetus if the mom pig gets the virus during the 1st or 2nd trimester?

Answer 12

Fetal death or Abortion

in 1st or 2nd trimester

Question 13

PMWS (Porcine circovirus 2)

can occur via the** transplacental route** as well as fecal-oral route which is the most common.

What happens to the fetus if the mom pig gets the virus during the

3rd trimester?

Answer 13

Usually nothing happens, minimal effect on fetus in 3rd trimester

Question 14

A farmer noticed that his 5 week old piglets were having

diarrhea, coughing, feeling lethargic, and not growing as fast as they should be.

A couple of the piglets had a yellowish discoloration of the skin.

The farmer reported no lesions on the skin of the piglets, but did mention that 2 of his pregnant pigs had aborted, 1 in the 1st trimester, and 1 in the second trimester.

Histopathology showed botyroid grape-like intracytoplasmic inclusions and necropsy of a dead piglet showed white necrotic foci in the liver, and multifocal necrosis in the kidneys. What is your diagnosis?

Answer 14

Porcine Circovirus 2 (PMWS)

Question 15

If a pregnant pig with PMWS was coinfected with *Porcine parvovirus *

what would you expect to happen with her pregnancy and the fetus?

Answer 15

Aborted fetus

or

Mummified or Stillborn fetuses

Question 16

A pig with PMWS is coinfected with another virus that is causing

interstitial pneumonia.

What virus is it?

Answer 16

Porcine Arterivirus (PRRS)

Question 17

A pig with PMWS is coinfected with something that is causing

chronic bronchopneumonia- an enzootic swine pneumonia.

What is the pathogenic agent?

Answer 17

Mycoplasma hyopneumoniae

Question 18

Two types of vaccines are used to treat Porcine Circovirus 2 (PMWS)

The chimeric vaccine utilizes ______ as genetic backbone for expression of capsid

protein of PCV2

while

the inactivated baculovirus-expressed vaccine includes the capsid protein from

________

Answer 18

Chimeric Vaccine - PCV1 as backbone

Inactivated baculovirus-expressed vaccine- includes capsid protein from PCV2

Question 19

A farmer notices that his older piglets are sporadically displaying

skin lesions that are red to black colored, m**ultifocal to coalescing, and look necrohemorrhagic on the perineal and hind limbs.

At necropsy, necrotizing vasculitis and fibrinous glomerulonephritis are discovered.

If you know this condition is associated with PCV2, what is your diagnosis?

Answer 19

Porcine Dermatitis and Nephropathy Syndrome (PDNS)

Question 20

A chicken farmer calls and is worried because his 3 week old chickens are

anorectic, lethargic, depressed, look pale, and are not gaining weight.

One of the sick chickens got in a fight and started bleeding, but the blood was watery and clotted slowly. Upon necropsy, it was noticed that the thymus and bursa of the chicken were atrophied. After taking a blood sample from a sick chickens, the PCV’s were all less than 27. This farm also has a history of Marek’s disease.

What is your diagnosis?

Answer 20

Chicken Infectious Anemia (Gyrovirus)

Question 21

The principal cells involved in Chicken Infectious Anemia are the

______ in bone marrow

__________ in thymic cortex

and

_____ and ______ cells in the spleen

Answer 21

Hemocytoblasts in bone marrow

Precursor-T cells in thymic cortex

CD4 and CD8 cells in spleen