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Flashcards in Past Exam 2006-2007 Deck (141)
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1

______________________________ is a halophilic organism common in shellfish that is a frequent cause of food poisoning in humans.

Vibrio parahemolyticus

2

______________________________ is the cause of severe osmotic diarrhea in humans and is most commonly associated with fecal contamination of food and water.

Vibrio cholerae

3

______________________________ is an organism frequently associated with esophageal lesions in feeder lambs that causes septicemia when it gains access to the blood.

Pasteurella trehalosi

4

______________________________ is an organism that dogs and causes the development of a hacking, paroxysmal cough of several days to weeks duration.

Bordetella bronchiseptica

5

______________________________ is an organism that can be detected in a dairy herd by testing a bulk tank sample of milk for antibody against the organism

______________________________ is an organism that can be detected in a dairy herd by testing a bulk tank sample of milk for antibody against the organism

6

______________________________ is the cause of contagious equine metritis.

Taylorella equigenitalis

7

______________________________ is an organism that produces a Afilamentous hemagglutinin@ and possibly pertactin and fimbriae that are thought to be involved in attachment to mammalian cells.

Bordetella bronchiseptica

8

___________________________ is a bacterial toxin that blocks the release of the neurotransmitters glycine and gamma-aminobutyric acid at the level of the spinal cord and brainstem

tetanospasmin

9

______________________________ is the organism most likely involved in the development of hemorrhagic bowel syndrome in cattle

Clostridium perfringens

10

______________________________ causes extensive myonecrosis that usually affects cattle 6 months to 2 years of age

Clostridium chauvoei

11

______________________________ causes mesocolonic edema in piglets 1-7 days of age and pseudomembraneous colitis in humans

Clostridium difficile

12

______________________________ infects wounds and causes the development of extensive subcutaneous pitting edema

Clostridium septicum

13

______________________________ is the bacterial organism considered to be the cause of foot-rot in cattle.

Fusobacterium necrophorum

14

______________________________ is an organism that is frequently transmitted to humans through the consumption of unpasteurized goat milk

Brucella melitensis

15

Briefly describe the mechanism of action of the leukotoxin of Mannheimia haemolytica

It is an RTX toxin (forms pores in the cell membranes of ruminant leukocytes and platelets

16

What was done to Haemophilus influenzae type b vaccines that altered the immune response from a T-cell independent to a T-cell dependent response?

The type b capsular polysaccharide was conjugated with a protein such as tetanus toxoid or mutant diphtheria toxin

17

What is the proposed mechanism by which infection with Enterococcus faecalis or Escherichia coli lead to increased susceptibility to systemic infection and severe purulent meningitis caused by Neisseria meningitidis?

Co-infection or prior infection with E. faecalis or E. coli stimulates the production of IgA antibody that cross-reacts with N. meningitidis antigens. Once N. meningitidis produces a systemic infection, this IgA binds to the organism and blocks IgM and IgG from binding. Since IgA is non-opsonic, the N. meningitidis is able to avoid phagocytosis and killing, resulting in a fulminating septicemia

18

List the two major methods by which Francisella tularensis is transmitted to humans.

Transmitted by ticks or other arthropod vectors

Contact with infected rabbits (often gains entrance via the mucous membranes or by ingestion

19

List two major obstacles that have made eradication of Brucella suis in the U.S. difficult

Feral swine and occasionally other wildlife such as reindeer can be infected and we are unable to eradicate these animals. Only way to get rid of the infection is to slaughter these animals.


The serologic test gave a lot of false positives

20

The available immunizing products for use against foot-rot in sheep are considered to have marginal efficacy because:

a. The vaccines stimulate a T-cell independent response against fimbrial antigens.
b. The vaccines do not stimulate a CMI response.
c. IgG is required for protection and the vaccines only stimulate an IgA response.
d. All the above.
e. Only a and b above.
f. None of the above.

NONE of the above

21

Which of the following organisms is least likely to require some type of inducing agent or co-infection in order to produce disease?

a. Actinobacillus equuli
b. Pasteurella multocida
c. Mannheimia haemolytica
d. Moraxella bovis
e. Dichelobacter nodosus

Actinobacillus equuli

22

Which of the following seems to be less of a problem in so called a high health status swine herds?

a. Contagious pleuropneumonia (APP)
b. Polyserositis (Haemophilus parasuis infection)
c. Atrophic rhinitis
d. All the above
e. Only a and b above.

Atrophic rhinitis

23

Tyzzer=s disease:

a. Most commonly affects lab rodents, wild rabbits and muskrats.
b. Causes a severe meningitis.
c. Causes a severe nephritis.
d. All the above.
e. Only a and c above.

Most commonly affects lab rodents, wild rabbits and muskrats.

24

Which of the following causes a disease in swine that is most similar to contagious pleuropneumonia?

a. Haemophilus parasuis
b. Mannheimia haemolytica
c. Actinobacillus suis
d. Pasteurella trehalosi
e. Bordetella bronchiseptica

Actinobacillus suis

25

The major economic loss associated with Haemophilus paragallinarum infection is:

a. Mortality due to respiratory disease.
b. Decrease in growth rate and lack of feed efficiency in broiler chickens.
c. Chronic lameness.
d. Immunosuppression that leads to serious problems with a variety of secondary invaders.
e. Loss of egg production in layer hens.

Loss of egg production in layer hens

26

Histophilus somni:

a. Is the most common cause of bacterial respiratory disease in sheep.
b. Produces a lipo-oligosaccharide that may play a role in apoptosis of endothelial cells.
c. Causes respiratory infection most commonly in late winter and early spring months.
d. Rarely produces systemic disease.
e. Requires a source of adenine, guanine and GMP or it will not grow

Produces a lipo-oligosaccharide that may play a role in apoptosis of endothelial cells.

27

Which of the following organisms has recently been incriminated as a cause of peritonitis in chickens and is thought by some to work in combination with Escherichia coli?

a. Bordetella avium
b. Actinobacillus seminis
c. Haemophilus paragallinarum
d. Gallibacterium anatis
e. Clostridium colinum

Gallibacterium anatis

28

Some members of the genus Bordetella:

a. Produce severe systemic infections after gaining access to the blood through the respiratory tract.
b. Destroy ciliated tracheal epithelium leading to secondary bacterial infection.
c. Are usually restricted to growth in the respiratory tract and do not invade other tissues.
d. Cause severe systemic disease by the elaboration of toxins.
e. Only a, b and d above.
f. Only b, c and d above.

Only b, c and d above

b. Destroy ciliated tracheal epithelium leading to secondary bacterial infection.
c. Are usually restricted to growth in the respiratory tract and do not invade other tissues.
d. Cause severe systemic disease by the elaboration of toxins.

29

Immunization against Moraxella bovis:

a. Has been difficult because there are several fimbrial types that must be protected against.
b. Killed bacterins have not been effective in stimulating an IgA response in the tears that is necessary for good protection.
c. The dominant cell antigens have stimulated only a weak T-cell independent response.
d. The killed bacterins have not stimulated a good CMI response that is necessary for preventing infection.
e. All the above.
f. Only a and b above
g. Only c and d above.

Only a and b above

a. Has been difficult because there are several fimbrial types that must be protected against.
b. Killed bacterins have not been effective in stimulating an IgA response in the tears that is necessary for good protection.

30

Therapy against botulism poisoning:

a. Requires aggressive antimicrobial therapy.
b. Requires timely treatment with polyvalent antitoxin.
c. Usually produces rapid improvement.
d. All the above.

Requires timely treatment with polyvalent antitoxin.