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Flashcards in Past Exam 2011/2012 Deck (76)
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1

_____ is the bacterium that contributes to hemorrhagic bowel syndrome in adult dairy cattle.

Clostridium perfringens Type A

2

____________________________ is an organism that creates some initial damage to the nasal turbinate epithelium of pigs that allows the subsequent colonization by Pasteurella multocida type D.

Bordetella bronchiseptica

3

____________________________ is the single most identifiable antecedent agent in Guillain-Barre syndrome in humans

Campylobacter jejuni

4

____________________________ is a cause of focal hepatic necrosis, jaundice and enterocolitis in laboratory rodents.

Clostridium piliforme

5

____________________________ is the cause of bacillary hemoglobinuria of cattle, deer, elk and sometimes sheep

Clostridium haemolyticum

6

____________________________ is commonly involved in shipping fever pneumonias in cattle and can cause meningoencephalitis and severe lameness when it establishes a septicemia.

Histophilus somni

7

____________________________ causes acute inflammation of the turbinates and air sacs of adult chickens which leads to depressed feed intake and a marked loss of egg production.

Haemophilus paragallinarum

8

____________________________ is a Clostridial organism that enters via wounds and causes pitting edema

Clostridium septicum

9

____________________________ is transmitted at a very early age and can cause severe polyserositis (peritonitis, pleuritis, pericarditis and joint infections) in pigs.

Haemophilus parasuis

10

___________________________ causes pseudomembraneous colitis in humans, horses and possibly other animals

Clostridium difficile

11

Severe___________________________ is the cause of death in human cholera

dehydration, fluid loss or diarrhea

12

_______________ is the major toxin involved in human cholera

Cholera toxin

13

____ and ____ are the capsular types of Pasteurella multocida that cause hemorrhagic septicemia

B and E

14

List three diseases commonly caused by Fusobacterium necrophorum in cattle

a. _Liver abscesses in feedlot cattle

b. _Post-partum metritis

c. _Foot rot

d. Calf diphtheria

15

Define toxico-infectious botulism?

It is a type of botulism where the organism is growing in the host (usually in the intestine or a wound) and elaborates one of the botulinum toxins which is absorbed and causes botulinum toxicity

16

Why is it not necessary to have a polyvalent immunizing agent against Clostridium tetani?

Because there is only a single toxin of importance (tetanospasmin) rather than multiple toxin types

17

Briefly describe the clinical disease syndrome caused by Campylobacter fetus subspecies venerealis in cows

Naive cows and heifers are bred or serviced using contaminated semen and the organism causes failure of implantation. The females can be bred multiple times over the course of 4-5 months but will not become pregnant until they clear the organism from the uterus. They are then immune from further problems

18

Why are serologic tests for infections caused by rough Gram-negative bacteria often adversely affected by a lack of specificity.

The core polysaccharide antigens are exposed and are more likely to be shared with other bacteria. Also, Igm is the type of antibody formed against many of the simple core polysaccharides and it is not as specific

19

Hyperimmune antiserum administered to foals with actinobacillosis is frequently of little or no value. List two reasons why the hyperimmune antiserum is not very effective

a. _Disease tends to be very acute and there is little time for hyperimmune antisera to have any effect.

b. It is thought that many of the affected foals have some congenital defects that compromise their ability to mount an immune response.

20

Several respiratory pathogens in this section produce RTX type toxins that are important virulence factors. These RTX toxins contribute to a marked increase in pathogenicity that is greater than the direct effects of the toxins on their target cells. What is the nature of this marked increase in pathogenicity?

Many of the RTX toxins are leukotoxins that are capable of lysing neutrophils. The neutrophils release their hydrolytic enzymes onto the host tissues, thus causing a lot of tissue damage not due to the direct activity of the leukotoxin on host cells

21

T or F Clostridium haemolyticum and C. novyii are transmitted by liver flukes.

False

22

T or F Brucella canis is common in feral dogs in developing countries

True

23

T or F RB51 is a modified-live strain of Brucella melitensis

False

24

T or F RB51 is infectious for humans

True

25

T or F Ranchers near Jackson Hole, Wyoming support the feeding program for elk because it means they have better pasture for their cattle despite the danger of brucella transmission

True

26

T or F Diagnosis of porcine intestinal adenomatosis is best accomplished by bacteriologic culture.

False

27

T or F Clostridium difficile is a common inhabitant of the normal adult equine intestine

False

28

T or F Blackleg of ruminants is usually diagnosed by demonstration of the principal toxin in typical lesions

False

29

T or F The Aprotective antigen@ is the most important immunogenic component for immunization against Clostridium chauvoei.

True

30

T or F In enterotoxemia of sheep, it is the epsilon toxin of Clostridium perfringens Type D that is the main cause of liquefactive necrosis, edema and hemorrhage in the brain.

True