Lesson 8b

Question 1

Its cell wall lipopolysaccharide are used as antigens in serotyping E. coli

Answer 1

Escherichia coli

Question 2

antigens are present in many strains and act as
adhesins facilitating attachment to mucosal surfaces

Answer 2

Proteinaceous fimbrial (F)

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

Answer 4

capsule

Question 5

released upon lysis or death of the bacteria, and produce pyrogenic activity

Answer 5

endotoxin

Question 6

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

Answer 6

fimbrial adhesins

Question 7

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

Answer 7

K88

Question 8

adhesins occur in calves

Answer 8

F41

Question 9

adhesins in calves and lambs

Answer 9

K99

Question 10

adhesins found only in older piglets

Answer 10

F18

Question 11

strains are important in post-weaning diarrhea and edema diseases

Answer 11

F18+

Question 12

an adhesin associated with attaching and effacing E. coli

Answer 12

intimin

Question 13

produce characteristic attaching and effacing lesions in which bacteria are intimately adherent 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

found most in pigs, induces hypersecretion of
fluid into the intestine through stimulation of
adenylate cyclase activity

Answer 15

LT1

Question 16

heat labile demonstrated in some ETEC strains
isolated from cattle

Answer 16

LT2

Question 17

toxin stimulates fluid and electrolyte
secretion into the small intestine and inhibits fluid absorption from the intestine by increasing
intracellular guanosine monophosphate isolated from porcine, bovine, ovine and human specimens

Answer 17

STa

Question 18

causes secretion of chloride and
bicarbonate ions as well as inhibition of absorption of sodium ions

Answer 18

STb

Question 19

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

Answer 19

enteric colibacillosis

Question 20

endotoxins produced during enteric colibacillosis

Answer 20

LT and STa

Question 21

fimbrial adhesins important for neonatal diarrhea in case of enteric colibacillosis

Answer 21

K88 and K99

Question 22

invade the bloodstream following infection of the intestines, lungs or navel ill

Answer 22

Colisepticaemia

Question 23

In poultry, colisepticaemia is called …..

Answer 23

coligranuloma (Hjarre’s disease)

Question 24

occurs 1 to 2 weeks after weaning in rapidly growing pigs

Answer 24

edema disease of pigs

Question 25

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

Answer 25

edema disease of pigs

Question 26

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

Answer 26

post weaning diarrhea

Question 27

major outbreaks of post weaning diarrhea of pigs are associated with …….

Answer 27

Enterotoxigenic E. coli; Enteropathogenic E. coli

Question 28

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

Answer 28

coliform mastitis

Question 29

virulence factor of Urogenital tract infection which facilitate mucosal colonization

Answer 29

fimbriae

Question 30

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

Answer 30

37°C for 24 to 48 hours

Question 31

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

Answer 31

metallic sheen

Question 32

On _______, colonies of E. coli are bright pink

Answer 32

MacConkey agar

Question 33

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

Answer 33

blood agar

Question 34

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

Answer 34

monoclonal antibodies

Question 35

For expression of fimbrial antigens, isolates should be subcultured on …………..

Answer 35

Minca medium