Pseudorabies and PMWS in Swine

Question 1

What is another name of Pseudorabies?

Answer 1

Aujeszky’s Disease

Question 2

What family is Pseudorabies in?

Answer 2

Herpesviridae (DNA, enveloped)

Question 3

In what disease in the Herpesvirus family do you not always see intranuclear inclusion bodies?

Answer 3

Pseudorabies

Question 4

What disease in the herpesvirus family is capable of jumping species (not humans)?

Answer 4

Pseudorabies

Question 5

Pseudorabies is eradicated in the US swine production, but why should we still be concerned about it?

Answer 5

Pseudorabies is endemic in wild swine populations in the southern US (chances of spread low, but backyard pigs could get it, need close interaction as it is herpes)

Question 6

In naive populations of swine, does Pseudorabies cause abortion?

Answer 6

Yes, up to 50% of sows will abort
Outcome of pregnancy determines fate (mummified, macerated, stillborn, weak or normal depending on if it crossed the placenta/which area)

Question 7

Which disease can prolong pregnancy in sows? Why would this happen? (Disease and virus family)

Answer 7

Pseudorabies (herpesvirus)
No fetal cortisol, or not enough fetal cortisol due to the amount of viable babies left (small liter from abortion, or mummified ones present)

Question 8

How does Pseudorabies effect piglets? (2 scenarios)

Answer 8

Non-immune sows – mortality 100% in piglets

Immune sows – maternal Ab protective, less severe disease in piglets with recovery

Question 9

How does Pseudorabies effect weaned, growing and mature swine? (3 phases)

Answer 9

1) Sneezing, coughing, constipation, vomiting
2) Incoordination, muscle spasms, excess salivation etc.
3) Moribund, mature swine have a low mortality with significant weight loss and poor growth rates

Question 10

How do secondary hosts (not pigs) get infected with Pseuodrabies?

Answer 10

Direct or indirect contact with swine

Question 11

What is the major sign of Pseudorabies in cattle?

Answer 11

Pruritis “mad itch”

Some cows have progressive CNS involvement with death in hours to weeks

Question 12

What are the clinical signs of Pseudorabies in dogs?

Answer 12

frenzy, pruritus, paralysis of jaw, drooling, howling NO tendency to attack

Question 13

What are the clinical signs of Pseudorabies in cats?

Answer 13

Death

Question 14

Is there viremia in Pseudorabies?

Answer 14

No (but infected ones are chronic shedders as it is a rabies virus)

Question 15

How does Pseudorabies virus reach the cranial nerve ganglia?

Answer 15

Travelling the axoplasm

Question 16

Where will you find gross lesions with Pseudorabies?

Answer 16

Occasional necrotic foci in the liver and spleen

Question 17

Where can microscopic lesions be found in swine with Pseudorabies?

Answer 17

CNS

Question 18

What is the standard test used to diagnose Pseudorabies?

Answer 18

Antibody ELISA

Question 19

How would you test a piglet fetus to see if it had Pseudorabies?

Answer 19

IF, virus isolation, and serum neutralization (detect antigen)

Question 20

What secretions are Pseudorabies shed in?

Answer 20

Saliva and nasal discharge

Question 21

What virus is possibly transmitted by rats and raccoons?

Answer 21

Pseudorabies

Question 22

Is there a vaccine for Pseudorabies?

Answer 22

Yes, used in endemic areas and around areas of outbreak

Question 23

If you have an outbreak of Pseudorabies at a farm, would you vaccinated your cat and dog?

Answer 23

Yes, or strict separation from pigs

Question 24

What virus family causes Postweaning Multisystemic Wasting Syndrome (PMWS)?

Answer 24

Circoviridae (DNA, naked)

Question 25

What are the other three forms of disease seen with PMWS?

Answer 25

1) Repro failure
2) Respiratory disease in finishing pigs
3) Porcine dermatitis and nephropathy syndrome (immunopathology, affects a few animals in a herd only)

Question 26

How is PMWS shed?

Answer 26

Feces

Question 27

What age group of piglets is protected via maternal Ab from PMWS?

Answer 27

6-9 weeks, then viral spread

Question 28

Why do you not test for PMWS with serology?

Answer 28

Circovirus is often in pig herds, but they may not be ill unless there are other stressors or viruses

Question 29

You arrive at a farm where several pigs are infected with Cirvovirus (PMWS), what would you recommend to the farmer?

Answer 29

Do NOT cull the entire herd
Early segregation and euthanasia of affected pigs
Vaccines