Small Ruminant Viruses

Question 1

What are the viral characteristics of bluetongue disease?

Answer 1

reoviridae, RNA, segemented

Question 2

How is blue tongue transmitted?

Answer 2

arbovirus

Question 3

Where does bluetongue occur in the world?

Answer 3

tropics and subtropics

Question 4

What is the most important economic loss of bluetongue?

Answer 4

major trade barrier

Question 5

What insect transmits blue tongue virus?

Answer 5

culicoides

Question 6

What is the reservoir for bluetongue virus?

Answer 6

subclinically infected cattle

Question 7

What are the viral characteristics of caprine arthritis-encephalitis?

Answer 7

retroviridae - RNA, enveloped

Question 8

What are the 2 syndromes associated with caprine arthritis-encephalitis and at what age do they occur?

Answer 8

encephalomyelitis in kids (2-4 months)

arthritis - older than 1 year

Question 9

What are the clinical signs associated with caprine - A-E?

Answer 9

lameness, wasting, but afebrile, alert, good appetite and sight, ascending paralysis, paddling

Question 10

What are the arthritis signs of caprine -A-E?

Answer 10

insidious onset over months/years, joints swollen and painful

Question 11

Where will you find lesions in necropsy of goats with caprine-A-E?

Answer 11

focal malacia in WHITE matter
joint lesions are of proliferative sinovitis
pneumonia

Question 12

How is caprine-A-E diagnosed?

Answer 12

antibody detection, test and remove

Question 13

How is caprine-A-E controlled?

Answer 13

no vax, transmission thru colustrum - can pasteurize colostrum to prevent

Question 14

What are the clinical signs of scrapie?

Answer 14

excitable, tremors, intense pruritus, deterioration over 1-6 months

Question 15

What are the necropsy lesions associated with scrapie?

Answer 15

gray matter - vacuolation, no inflammation

Question 16

What test can be used to diagnose scrapie?

Answer 16

IHC and western blot on CSF

Question 17

What family is maedi?

Answer 17

retroviridae

Question 18

What is maedi called in the US?

Answer 18

ovine progressive pneumonia

Question 19

What are the clinical signs of maedi?

Answer 19

insidious onset, not recognized until 3 years old

jerking of head and flared nostrils, nasal discharge and cough, abort, immunosuppresion

Question 20

What are the necropsy lesions associated with maedi?

Answer 20

lungs and LN - HOMOGENOUSLY consolidated nodules, lungs don’t collapse

Question 21

What is the most commonly used test for maedi?

Answer 21

antibody ELISA

Question 22

What is a more sensitive test that can be used for maedi?

Answer 22

WB, PCR

Question 23

How is maedi transmitted?

Answer 23

Directly and indrectly (not typical of retros)

Question 24

How is maedi controlled?

Answer 24

avoiding transmission –> biting arthropods, surgical equipment mechanically

Question 25

What family is ovine pulmonary adenomatosis?

Answer 25

retroviridae

Question 26

What can not be used to diagnose ovine pulmonary adenomatosis?

Answer 26

cell culture - doesn't grow on it

Question 27

What is the incubation time for ovine pulmonary adenomatosis?

Answer 27

years, but shorter in lambs

Question 28

How are the clinical signs of ovine pulmonary adenomatosis different from maedi?

Answer 28

large amounts of surfactant containing viscous fluid produced by tumor cells Lesions in lung are nodular

Question 29

What kind of tumors come from ovine pulmonary adenomatosis?

Answer 29

adenomas and adenocarcinomas - metastasis

Question 30

Where is OPA secreted?

Answer 30

in saliva and respiratory secretions

Question 31

What are 2 other names for Orf?

Answer 31

contagious ecthyma, scabby mouth

Question 32

What viral family is Orf?

Answer 32

Poxviridae - replicates in cytoplasm

Question 33

Where are scabby lesions found on the sheep?

Answer 33

muzzle, within the mouth esp lambs, rarely on eyelids, feet and teats

Question 34

What makes Orf so hard to eradicate from a flock?

Answer 34

reinfection, chronic infections, resistance in environment

Question 35

How can Orf be prevented?

Answer 35

ewes vaccinated weeks before lambing --> applied by scarified skin, short lived immunity