Edmundson Final Material (BVDV, Johne's, Parasites)

Question 1

What are the two BIOTYPES of BVDV?

Answer 1

Cytopathic
Non-cytopathic

*how it behaves in cell culture

Question 2

The 3 manifestations of disease seen with BVDV

Answer 2

Acute infections
Persistent Infections
Mucosal Disease

Question 3

Describe how a PI animal is made

Answer 3

infected with a NCP strain prior to 125d gestation

BEFORE animal is immunocompetent

Question 4

Most acute infections with BVDV show what clinical sign(s)

Answer 4

mild fever, leukopenia

SUBCLINICAL

Question 5

Severe acute infections with BVDV have been mostly associated with which genotype of the virus?

Answer 5

Type 2 (BVDV-2)

Question 6

With mucosal disease, which biotype is causing the lesions?

Answer 6

CP strain

Question 7

How does BVDV lead to diarrhea?

Answer 7

Causes blunting of intestinal crypts

Question 8

BVDV is maintained in which cells?

Answer 8

mononuclear phagocytic cells (WBCs)

Question 9

For which 3 diagnostic tests can Ab interference be a problem?

Answer 9

Virus isolation
ACE (ELISA)–if you use serum
RT-PCR

Question 10

The gold standard (most reliable) method for detection of BVDV

Answer 10

Virus isolation & culture

Question 11

Concerning the use of skin samples for ELISA and IHC, which test requires the samples to be fixed in formalin?

Answer 11

IHC

DO NOT formalin fix tissues for ELISA

Question 12

If screening samples from a whole herd, which diagnostic test would be the best choice?

Answer 12

RT-PCR

Question 13

What does each of the following detect:

1) ELISA
2) Serology

Answer 13

1) Antigen

2) antibody

Question 14

Which diagnostic test is best for diagnosis of PI animals

Answer 14

IHC (skin sample in formalin)

Question 15

Causative agent of Johne’s disease

Answer 15

Mycobacterium avium ss. paratuberculosis (MAP)

Question 16

Primary route of transmission for Johne’s? Primary source?

Answer 16

Fecal-oral

Infected animals are primary source (dam–>offspring)

*Infected as CALVES

Question 17

What causes the visible thickening of the intestine that occurs with Johne’s?

Answer 17

infiltration of macrophages and lymphocytes

Question 18

For which segment of intestine does MAP have a predilection?

Answer 18

Ileum

Question 19

T/F: Johne’s diarrhea is usually severe & very watery but lacks blood and mucus

Answer 19

TRUE!!

also no tenesmus

Question 20

What are the 4 stages of infection with Johne’s?

Answer 20

Stage 1–silent infection
Stage 2–unapparent carrier
Stage 3–clinical disease
Stage 4–advanced clinical disease

Question 21

At which stage do animals begin producing detectable antibodies against MAP?

Answer 21

Stage 3–clinical disease

Question 22

Major consequence of infection with Johne’s?

Answer 22

Protein losing enteropathy

leads to bottle jaw!

Question 23

Why is the sensitivity of most diagnostic tests so low?

Answer 23

Humoral response to the organism is delayed

Question 24

Which stages are undetectable by Fecal and tissue culture?

Answer 24

Stage 1 & 2 (not useful for screening)

Question 25

Which diagnostic test is most widely used for johne's and why?

Answer 25

ELISA--useful for screening herds, inexpensive, fast

Question 26

Which type of cattle are at highest risk for intestinal parasites?

Answer 26

Calves during first grazing season

Question 27

Which parasite of the HOTC complex has become the most prevalent internal parasite in US cattle operations?

Answer 27

Cooperia spp.

Question 28

Small ruminants are most severely impacted by which parasite?

Answer 28

Haemonchus contortus

Question 29

Define type 1 and type 2 ostertagiasis & when they occur in the south

Answer 29

Type 1--when the ingested larva invade gastric glands (Spring) Type 2--when hypobiotic larvae emerge from gastric glands (Fall)

Question 30

Age associated with: 1) type 1 ostertagiasis 2) Type 2 ostertagiasis

Answer 30

1) young animals (overstocking) | 2) older (1-2yr)

Question 31

When do you want to treat for Ostertagia?

Answer 31

When chances of re-exposure are low (i.e. summer in the south)

Question 32

Which part of the GI tract does Cooperia parasitize?

Answer 32

small intestine *do NOT feed on blood*

Question 33

Which dewormer is effective for tx of cooperia?

Answer 33

Benzimidazoles

Question 34

Which parasite is a common cause of diarrhea in kids 1-4months old (associated with stress)

Answer 34

Coccidia (Eimeria spp.)

Question 35

In which segment of the GI tract can you find Haemonchus?

Answer 35

Abomasum--pierce mucosa and cause protein and plasma loss

Question 36

3 classes of dewormers commonly used in goats

Answer 36

Benzimidazoles Imidathiazol Macrolides

Question 37

Which macrolide is not recommended for use and why?

Answer 37

Doramectin--increases resistance due to prolonged presence

Question 38

Biggest facotr affected the rate of development of resistance?

Answer 38

Refugia

Question 39

In goats, which two methods of dewormer administration contribute to resistance?

Answer 39

pour-on dewormers Injecting **ALWAYS give orally, OVER THE TONGUE

Question 40

When dosing goats, how much dewormer do you give compared to sheep/cattle?

Answer 40

2x the dose for all dewormers except levamisole For levamisole--1.5x dose (more toxicity)