Porcine circovirus associated disease

Question 1

What is PCVAD?

Answer 1

a group of diseases associated with common underlying viral infection PCV2

Question 2

To diagnose PCVAD, what must be present?

Answer 2

1. clinical signs
2. hallmark microscopic lesions
3. virus in lesion

Question 3

Why is PCV2 necessary but insufficient cause to dx PCVAD?

Answer 3

because it is ubuiquitous and most pigs become infected with PCV2, some get dz

Question 4

what are the two clusters of PCV2?

Answer 4

2a and 2b

2a is in the vaccines

Question 5

What is the epidemiology of PCV2?

Answer 5

1. ubiquitous, stable, resistant
2. infection may be asymptomatic/subclinical
3. overt disease requires co-factors that enhanced PCV2 replication

Question 6

What are factors that influence the expression of PCV2>

Answer 6

1. poor managemnet
2. PRRS
3. mycoplasma hyopneumniae
4. SIV
5. parvovirus
6. unknowns
7. genetics
8. vaccine status

Question 7

What type of herd presentations of PCV2 are there?

Answer 7

epizootic
endemic
reproductive

Question 8

What are the clinical signs of post-weaning multisystemic wasting syndrome?

Answer 8

1. elevated mortality
2. weight lost, wasting
3. pallor (jaundice)
4. diarrhea (grow, finish)
5. dyspnea

Question 9

What are the clinical signs of reproductive presentation of PCV2?

Answer 9

1. elevated mummies, still births, abortions etc
2. often start-up herds without vaccination program
3. still birthws with non-suppurative necrotizing myocarditis with PCV2 antigen!

Question 10

What is the lesion seen in still births caused by PCV2?

Answer 10

non-suppurative necrotizing myocarditis with PCV2 antigen

Question 11

What stages of gestation are affected by PCV2>

Question 12

What stage of gestation does PCV2 affect? PRRS? parvovirus?

Answer 12

1. multiple (

Question 13

What is the pathogenesis of PCVAD?

Answer 13

1. predilection for dendritic cells and macrophages
2. these cells accumulate PCV2, viral persistence
3. modified DC function, impaired innate pathogen recognition signals and antigen presentation
4. lymphoid depletion
5. immunosuppresion
6. seroconversion (some pigs remain persistenly viremic and asymptomatic)

Question 14

What is the role of immune stimulation in PCVAD-PMWS?

Answer 14

a near simultaneous immune stimulation is associated with higher PCV2 replication in tissues, which is positively correlated with severity of disease

Question 15

Why would you be concnerend with using vaccines (especially mycoplasma vaccines) in nursery animals with PCV2 viremia?

Answer 15

ecuase immune stimulation while the pig is infected can restul in massive replication of PCV in tissue

Question 16

What is the pathology of PCV2?

Answer 16

1. lymphoid tissues: lymphadenopathy–depletion and granulomatous inflam, thymic atrophy
2. liver: hepatocyte necrosis, icterus
3. lung: interstitial pneumonia
4. kidney: intersitial nephritis (white foci)
5. GIT: granulomatous enteritis

Question 17

What two diseases cause white foci in liver?

Answer 17

lepto

PCV2

Question 18

What is the most appropriate tool for defninitive diagnosis of PCV2?

Answer 18

IHC

Question 19

How is definitive diagnosis achieve with PCV2?

Answer 19

Multiple tissues from multiple pigs
Must fulfill case deinition
1. clinical signs
2. histologic lesions: lymphoid depletion, granulomatous inflam
3. virus in lesions (IHC)

Question 20

What is treatment of PCV2?

Answer 20

supportive care

mass medication/anti-inflammatory for secondary disase

Question 21

What is control/prevention of PCV2?

Answer 21

1. control concurrent dz
2. reduce immune stimulation
3. implement good production practices
4. vaccination

Question 22

What are the different PCV2 vaccines available?

Answer 22

1. ingelvac/circoFLEX is capsid protein for piglets
2. PCV2-1 chimera for piglets
3. PCV2 capsid protein piglets
4. inactivated PCV2: sows, piglets

Question 23

What does PCV2 vaccination do?

Answer 23

extremely efficacious!!!!!
piglet
1. decreased mortality
2. decreased viral load
3. increased ADG
4. decreased growth variation