Testing

Question 1

What must the virus be like for isolation to be possible?

Answer 1

Stable outside the host

Question 2

What must a viral transport medium do?

Answer 2

Inhibit bacteria

Question 3

Why is virus isolation not often done?

Answer 3

takes a long time

Question 4

Why is EM rarely used?

Answer 4

Expensive, high expertise

Question 5

How can you confirm a haemagglutination test?

Answer 5

Haemagglutination inhibition

Question 6

How do you detect viral antigen?

Answer 6

Polyclonal or monoclonal antibodies

Question 7

What are two ways you can identify a virus by incubation with antibody?

Answer 7

Direct detection or two antibody system

Question 8

What can you label antibody with?

Answer 8

Fluorescein, peroxidase, colloidal gold

Question 9

What can you do on an immobilisaed antigen?

Answer 9

Immunohistology or captures antigen

Question 10

What do Rapid Immunomigration tests do for FeLV?

Answer 10

Use blood, saliva or tears to look for p27

Question 11

How do in house test kits for FeLV-antigen or parvo work?

Answer 11

ELISA

Question 12

What’s an advantage of PCR?

Answer 12

Fast

Question 13

What’s a disadvantage of PCR?

Answer 13

False positives due to contamination

Question 14

How can you get false negatives due to PCR?

Answer 14

Intermittent virus shedding

Question 15

What does more PCR cycles mean?

Answer 15

Less virus present

Question 16

What are the three types of antibodies?

Answer 16

Maternally derived (6-8 weeks), from vaccination (DIVA), from previous or current infection (rising titre or IgM)

Question 17

How do you test for calicivirus or herpesvirus?

Answer 17

Viral isolation

Question 18

What should you do if you get a positive FeLV test?

Answer 18

Re-test in 12 weeks, if negative could be latent infection so do bone marrow PCR

Question 19

How do you diagnose FIV?

Answer 19

Antibody test (ELISA or RIM), confirm with PCR or Western Blot

Question 20

Why is FIP hard to diagnose?

Answer 20

If coronavirus antibody is high this only shows exposure, and PCR cannot differentiate between FIP and enteric coronavirus

Question 21

SO how should you diagnose FIP?

Answer 21

Do antibody titre and PCR, and diagnose if margin or error is high

Question 22

Why is coronavirus isoaltion difficult?

Answer 22

Fragile

Question 23

When can you get a false negative in bacteria?

Answer 23

If on antibiotics

Question 24

How do you take a sample for blood culture?

Answer 24

In a meat broth

Question 25

Where can you find anaerobes?

Answer 25

Abscess, endometritis, pyothorax

Question 26

How long do anaerobes survive in air?

Answer 26

No more than 20 minutes

Question 27

What happens if you refrigerate anaerobes?

Answer 27

Kills them

Question 28

How can you determine antibiotic sensitivity?

Answer 28

Broth dilution MIC or agar gel diffusion

Question 29

What’s the problem with sensitivity testing?

Answer 29

Only for aerobic bacteria and variable in vivo tissue penetration

Question 30

In which species should you not use intradermal TB testing?

Answer 30

Ctas

Question 31

When can you get false positives in intradermal TB testing in dogs?

Answer 31

Due to cross-reactivity

Question 32

Where do you TB test dogs?

Answer 32

Inner pinna

Question 33

Why is serology for Mycoplasma unreliable?

Answer 33

Cross-react

Question 34

What’s the problem with bacterial isolation from biopsy?

Answer 34

Needs special media and techniques

Question 35

Which method is not available for avian, human and bovine mycobacteria?

Answer 35

PCR

Question 36

How do you submit swabs for yeast culture?

Answer 36

Bacterial transport medium

Question 37

What is easier to stain for yeast than sellotape?

Answer 37

Smear