Lesson 8b Flashcards
Its cell wall lipopolysaccharide are used as antigens in serotyping E. coli
Escherichia coli
antigens are present in many strains and act as
adhesins facilitating attachment to mucosal surfaces
Proteinaceous fimbrial (F)
Give the virulence factors of pathogenic strains of E. coli
- capsules
- endotoxins
- adherence and colonization
- enterotoxin
interfere with the phagocytosis and with the antibacterial effectiveness of the
capsule
released upon lysis or death of the bacteria, and produce pyrogenic activity
endotoxin
allow attachment to mucosal surfaces and facilitates colonization by diminishing the expulsive effects of peristalsis and the
flushing effect of urine
fimbrial adhesins
most common adhesin present in strains of E. coli infecting pigs
K88
adhesins occur in calves
F41
adhesins in calves and lambs
K99
adhesins found only in older piglets
F18
strains are important in post-weaning diarrhea and edema diseases
F18+
an adhesin associated with attaching and effacing E. coli
intimin
produce characteristic attaching and effacing lesions in which bacteria are intimately adherent to the host epithelial cell membrane with
marked rearrangement of the cytoskeleton
Attaching and effacing E. coli (AEEC)
Derivatives of endotoxins of E. coli
- enterotoxin
- shigatoxins
- verotoxins
- cytotoxic necrotizing factors
found most in pigs, induces hypersecretion of
fluid into the intestine through stimulation of
adenylate cyclase activity
LT1
heat labile demonstrated in some ETEC strains
isolated from cattle
LT2
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
STa
causes secretion of chloride and
bicarbonate ions as well as inhibition of absorption of sodium ions
STb
Common under intensive systems of management due to build-up of infection in the environment
enteric colibacillosis
endotoxins produced during enteric colibacillosis
LT and STa
fimbrial adhesins important for neonatal diarrhea in case of enteric colibacillosis
K88 and K99
invade the bloodstream following infection of the intestines, lungs or navel ill
Colisepticaemia
In poultry, colisepticaemia is called …..
coligranuloma (Hjarre’s disease)
occurs 1 to 2 weeks after weaning in rapidly growing pigs
edema disease of pigs
What disease is produced by isolated noninvasive E. coli strains which replicate in the tract and produce a shigatoxin (ST2e)
edema disease of pigs
occurs within a week or two after weaning, often following changes in feeding regimens or in management and with possible
involvement of rotaviruses
post weaning diarrhea
major outbreaks of post weaning diarrhea of pigs are associated with …….
Enterotoxigenic E. coli; Enteropathogenic E. coli
Infection of the mammary glands of cows and sows by members of the Enterobacteriaceae, including E. coli
coliform mastitis
virulence factor of Urogenital tract infection which facilitate mucosal colonization
fimbriae
In E. coli infections, specimens cultured on blood and MacConkey agar are incubated aerobically at what temp. and how many hours
37°C for 24 to 48 hours
The colonies of some E. coli strains have a ______ on EMB agar
metallic sheen
On _______, colonies of E. coli are bright pink
MacConkey agar
On ______, colonies of E. coli are greyish, round and shiny with a characteristic smell
blood agar
Enterotoxins in the small intestine can be detected, using methods employing ______
monoclonal antibodies
For expression of fimbrial antigens, isolates should be subcultured on …………..
Minca medium
