Circoviridae Flashcards
What are the 2 genuses in family Circovridae?
- Circovirus*
- Gyrovirus*
Chicken infectious anemia is part of genus _________
Gyrovirus
Which disease of genus circovirus affects birds?
Psittacine beak and feather disease virus
Which porcine virus is non-pathogenic?
Porcine circovirus Type 1
*Porcine circovirus type 2 *is also known as
PMWS (Post-weaning Multisystemic Wasting Syndrome)
Describe the DNA of family Circoviridae
circular SSDNA
Both genuses *Circovirus *and Gyrovirus have circular SSDNA, but one is
negative sense SSDNA
and one is
ambisense SSDNA
- Circovirus -ambisense*
- Gyrovirus- negative sense*
**Trumpet-like structures **are seen on the surface of which genus of Circoviridae?
Gyrovirus (Chicken Infectious Anemia)
Circoviruses are small, non-enveloped, spherical viruses with
________ symmetry
Icosahedral symmetry
Circoviruses replicate in actively dividing cells, but replication of their circular SSDNA occurs in the ________
nucleus
PMWS or Porcine circovirus Type 2
is found in all secretions and _________ transmission is the most common route
fecal-oral
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?
Fetal death or Abortion
in 1st or 2nd trimester
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?
Usually nothing happens, minimal effect on fetus in 3rd trimester
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?
Porcine Circovirus 2 (PMWS)
If a pregnant pig with PMWS was coinfected with *Porcine parvovirus *
what would you expect to happen with her pregnancy and the fetus?
Aborted fetus
or
Mummified or Stillborn fetuses
A pig with PMWS is coinfected with another virus that is causing
interstitial pneumonia.
What virus is it?
Porcine Arterivirus (PRRS)
A pig with PMWS is coinfected with something that is causing
chronic bronchopneumonia- an enzootic swine pneumonia.
What is the pathogenic agent?
Mycoplasma hyopneumoniae
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
________
Chimeric Vaccine - PCV1 as backbone
Inactivated baculovirus-expressed vaccine- includes capsid protein from PCV2
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?
Porcine Dermatitis and Nephropathy Syndrome (PDNS)
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?
Chicken Infectious Anemia (Gyrovirus)
The principal cells involved in Chicken Infectious Anemia are the
______ in bone marrow
__________ in thymic cortex
and
_____ and ______ cells in the spleen
Hemocytoblasts in bone marrow
Precursor-T cells in thymic cortex
CD4 and CD8 cells in spleen
