AG MED - GI - JOHNE’S DISEASE

Question 1

What is paratuberculosis?

Answer 1

Question 2

What organism causes paratuberculosis?

Answer 2

Question 3

Difference in semantics between Johne’s disease and paratuberculosis

Answer 3

Question 4

Herd prevalence of paratuberculosis

Answer 4

Question 5

Herd losses due to paratuberculosis

Answer 5

Question 6

Economic losses due to paratuberculosis

Answer 6

Question 7

Paratuberculosis epidemiology

Amount of death loss at any one time:

Onset often associated with:

Infected primarily as calves by:

Adult infection:

See signs earlier with:

Answer 7

Question 8

Epidemiology of paratuberculosis

When is MAP shed?

Where does MAP persist and for how long?

Answer 8

Question 9

Epidemiology of paratuberculosis

Major route of infection:

Colostrum and milk:

Transplacental transmission:

Sexual transmission:

Answer 9

Question 10

Paratuberculosis

For every clinical case _____ % of herd probably infected.

Detect only _______ % of these with current techniques.

If 25-30% are clinical:

Answer 10

Question 11

What is the incubation period for paratuberculosis?

How long are animals clinical on average?

What is the course of “pipe stream diarrhea”?

Answer 11

Question 12

Clinical signs of paratuberculosis

Weight:
Appetite:
Attitude:
Appearance (2):

Answer 12

Question 13

Clinical pathology of paratuberculosis

Early stages:

Advanced
Protein, albumin, globulins:
Calcium, sodium, potassium:
RBC:
Phosphate:

Answer 13

Question 14

What are the four stages of paratuberculosis?

Answer 14

Question 15

Paratuberculosis Stage I

Description:

Age at infection:

Diarrhea:

Organism location:

Histology/culture:

Answer 15

Question 16

Paratuberculosis Stage II

Description:

Diarrhea:

Antibodies:

Other diseases:

Fecal culture:

Environment:

Answer 16

Question 17

Paratuberculosis Stage III

Description:

Weight:

Diarrhea:

Thirst/appetite:

Fecal culture:
Fecal PCR:
Ab ELISA/AGID:

Answer 17

Question 18

Paratuberculosis Stage IV

Description:

Condition:

Diarrhea:

Death:

Answer 18

Question 19

What are two testing strategies for paratuberculosis?

Answer 19

Question 20

Spectrum of Immune Response to MAP

(Graph)

Cellular response
Humoral response
Bacterial load and shedding

Answer 20

Question 21

Antibody based tests for paratuberculosis

What are the three tests?

Which would you use for animals with clinical signs?

Which isn’t good for individuals (unless they have advanced clincial disease) but is good for herds and groups?

Which has low sensitivity and specificity?

Answer 21

Question 22

What are the two main antigen/organism based tests for paratuberculosis?

Which is the gold standard?

Cons of the gold standard?

Answer 22

Fecal culture and PCR
*Others = intradermal/IV Johnin test, biopsy of ileocecal junction/lymph node, and gamma interferon CMI test

Fecal culture is the gold standard; detect 1-4 years prior to clinical signs

Fecal culture is expensive ($50 WADDL) and time consuming (up to 6 months in sheep); prone to contaminants

Question 23

PCR can be used to find MAP DNA fragments in what four things?

PCR can be used in combination with what test?

Three advantages of PCR:

Four disadvantages of PCR:

Answer 23

Feces, blood, milk, tissues (liver, lymph nodes, etc)

Combined with culture

Higher sensitivity, higher specificity, automation

Inhibitors, contaminants, less availability, expensive

Question 24

Immune response for paratuberculosis

MAP is taken up by which two groups of cells?

How does the organism survive?

How does the infection spread?

What happens as mycobacteria-laden macrophages accumulate?

Answer 24

Question 25

Immune response to paratuberculosis

What does immunity to MAP depend upon?

Is humoral immunity effective?

What is required to kill MAP macrophages?

What cells are the major contributor to the immune response?

Answer 25

Question 26

Immune response to paratuberculosis

What happens to the cell mediated immunity towards the end of the subclinical phase?

Answer 26

Question 27

Why is control of paratuberculosis difficult? (6)

Answer 27

Question 28

Treatment for paratuberculosis?

Answer 28

Question 29

What might you see postmortem with paratuberculosis?

Answer 29

Question 30

Control strategy for Johne’s

2.

Answer 30

Question 31

Vaccination for paratuberculosis

Does it decrease infection?

Does it interfere with testing?

Are there health risks?

Is it used in the United States?

Answer 31