Lesson 8a, 8b

Question 1

Act as adhesins in E. coli facilitating attachment to mucosal surfaces

Answer 1

Proteinaceous fimbrial (F)

Question 2

Give three parts of the E. coli that can be utilized as antigens for serotyping E. coli

Answer 2

Somatic (O), flagellar (H) capsular (K) antigens

Question 3

Give the virulence factors of pathogenic strains of E. coli

Answer 3

1. capsules
2. endotoxins
3. adherence and colonization
4. enterotoxin

Question 4

Interfere with the phagocytosis and with the antibacterial effectiveness of the complement system

Answer 4

Capsule

Question 5

Released upon lysis or death of the bacteria then produce fever, DIC, endotoxic shock

Answer 5

Endotoxin

Question 6

Allow attachment to mucosal surfaces and facilitates colonization by reducing the expulsive effects of peristalsis and the flushing effect of urine

Answer 6

Fimbrial adhesins

Question 7

What is the most common adhesin present in strains of E. coli infecting pigs

Answer 7

K88

Question 8

E. coli adhesins present in calves

Answer 8

F41

Question 9

E. coli adhesins in calves and lambs

Answer 9

K99

Question 10

Adhesins found only in older piglets due to lack of receptors in younger piglets

Answer 10

F18

Question 11

These E. coli strains are important in post-weaning diarrhea and edema diseases in older piglets

Answer 11

F18+

Question 12

An adhesin associated with attaching and effacing E. coli

Answer 12

Intimin

Question 13

These E. coli are adhere to the host epithelial cell membrane with marked rearrangement of the cytoskeleton

Answer 13

Attaching and effacing E. coli (AEEC)

Question 14

Derivatives of endotoxins of E. coli

Answer 14

1. enterotoxin
2. shigatoxins
3. verotoxins
4. cytotoxic necrotizing factors

Question 15

What type of enterotoxin is common in pigs and induces hypersecretion of fluid into the intestine through stimulation of adenylate cyclase activity?

Answer 15

LT1

Question 16

Heat labile enterotoxin demonstrated in some ETEC strains isolated from cattle?

Answer 16

LT2

Question 17

This toxin produced by E. coli influence fluid and electrolyte secretion of the small intestine and inhibits fluid absorption

Answer 17

STa (heat-stable enterotoxin)

Question 18

Which heat-stable toxin of E. coli causes secretion of chloride and bicarbonate ions and inhibit sodium absorption?

Answer 18

STb

Question 19

STa of E. coli cause diarrhea through increasing ____ _____

Answer 19

guanosine monophosphate

Question 20

Common under intensive systems of management due to build-up of infection in the environment

Answer 20

enteric colibacillosis

Question 21

endotoxins produced during enteric colibacillosis

Answer 21

LT and STa

Question 22

Which fimbrial adhesins are important for neonatal diarrhea in case of enteric colibacillosis?

Answer 22

K88 and K99

Question 23

Common under intensive systems of management due to build-up of infection in the environment affecting newborn calves, lambs and piglets

Answer 23

Enteric colibacillosis

Question 24

In poultry, colisepticaemia is referred to as _____ characterized by chronic inflammatory changes resembling tuberculous lesions

Answer 24

Coligranuloma (Hjarre’s disease)

Question 25

Occurs 1 to 2 weeks after weaning in rapidly growing pigs

Answer 25

Edema disease of pigs

Question 26

Which toxin is produced by noninvasive E.coli that damages endothelial cells with consequent perivascular edema?

Answer 26

ST2e

Question 27

What disease is produced by isolated noninvasive E. coli strains which replicate in the tract and produce a shigatoxin (ST2e)

Answer 27

edema disease of pigs

Question 28

Occurs within a week or two after weaning, after changes in feeding regimens or in management and with possible involvement of rotaviruses

Answer 28

Post-weaning diarrhea of pigs

Question 29

Majority outbreaks of post-weaning diarrhea in pigs are associated with?

Answer 29

Enterotoxigenic E. coli (ETEC)

Question 30

Infection of the mammary glands of cows and sows by members of the Enterobacteriaceae, including E. coli

Answer 30

Coliform mastitis

Question 31

In E. coli infections, specimens cultured on blood and MacConkey agar are incubated aerobically at what temp. and how many hours

Answer 31

37°C for 24 to 48 hours

Question 32

The colonies of some E. coli strains have a ______ on EMB agar

Answer 32

metallic sheen

Question 33

On _______, colonies of E. coli are bright pink

Answer 33

MacConkey agar

Question 34

On ______, colonies of E. coli are greyish, round and shiny with a characteristic smell

Answer 34

Blood agar

Question 35

Enterotoxins in the small intestine can be detected, using methods employing ______

Answer 35

Monoclonal antibodies

Question 36

For expression of fimbrial antigens, isolates should be subcultured on?

Answer 36

Minca medium

Question 37

Identify the 3 major enteric and systemic pathogens

Answer 37

Escherichia coli Salmonella serotypes Yersinia species

Question 38

Name atleast 3 opportunistic pathogens of Enterobacteriaceae

Answer 38

Proteus species Enterobacter species Klebsiella species

Question 39

Give at least 2 non-pathogenic enterobacteriaceae

Answer 39

Hafnia sp. and Erwinia sp.

Question 40

Formerly used to describe enterobacteria capable of fermenting lactose

Answer 40

Coliform