Escherichia coli - Exam 2

Question 1

E. coli is a gram ______ bacteria.

Answer 1

Negative

Question 2

True/False. E.Coli is part of the normal flora of animals.

Answer 2

True

Question 3

How is strain identification of E. coli commonly done?

Answer 3

Serotyping (ID of bacterial O:K:F:H antigens) and virotyping (ID by specific toxic activity, virulence factor or virulence gene)

Question 4

What are the antigens of E. coli?

Answer 4

O - LPS

K - capsule

H - flagella

F or P - adhesins

Question 5

What are the clincal signs for enterotoxigenic E. coli?

Answer 5

Diarrhea is water and non-bloody

Minimal inflammatory changes

Question 6

Which E. coli causes edema disease in weaned pigs?

Answer 6

Shigatoxigenic E. coli

Question 7

Which species/age group does enterotoxigenic E. coli affect?

Answer 7

Neonatal and weaned pigs

Neonatal calves and lambs

Dogs and horses

Question 8

How is E. coli typically transmitted?

Answer 8

Fecal-oral route

Question 9

What is the virulence factor for enteropathogenic E. coli?

Answer 9

Bundle forming pilus

Question 10

What protein is used for attachment by enterpathogenic E. coli? What is the effect of the attachment?

Answer 10

Initimin is an E. coli protein for attachment

Causes the collapse of microvilli in distal small intesting and upper large intestine

Question 11

What are the clinical sings of enteropathogenic E. coli?

Answer 11

Watery diarrhea in all animals

No blood or leukocytes

Question 12

Which type of E. coli is the causative agent for neonatal colibacillosis and colisepticemia in pigs?

Answer 12

Enterotoxigenic E. coli

Question 13

Which type of E. coli has zoonotic potential?

Answer 13

Enterohemorrhagic E. coli

Question 14

What does E. coli cause in dogs?

Answer 14

Colisepticemia in neonatal pups

Pyometra in bitches

Lower UTIs

Question 15

What does E. coli cause in poultry?

Answer 15

Omphalitis

Colisepticemia

Coligranuloma

Question 16

What is the disease caused by E. coli that is a peracute condition that results in death due to endotoxemia?

Answer 16

Coliform mastitis

Question 17

How do you diagnose enteric disease caused by E. coli?

Answer 17

Fecal sample for culture

Question 18

What test would you use to test for Lipid A?

Answer 18

Limulus Amebocyte (LAL) Test

Lipid A is the endotoxin of gram negative bacteria

Question 19

What is the benefit of having the family of enterobacteriaceae as part of the normal flora in the GI tract?

Answer 19

Microbial antagonism - protect GI tract against foreign bacteria

Breakdown and adsorption of the food

Waste processing

Vitamin K production

Question 20

What are the most prevalent bacteria in nosocomial infections?

Answer 20

Infections acquired from the hospital

Klebsiella pneumonia

Klebsiella oxytoca

Enterobacter cloacae

Proteus mirabilis

Citrobacter freundii

Question 21

Which enterotoxins of E. coli cause diarrhea?

Answer 21

AB toxins

They are heat liable and stable, both plasmid encoded

Question 22

What are the virulence factors of necrotoxigenic E. coli (NETC) and what does it cause?

Answer 22

Cytotoxic necrtizing factors 1 and 2 (cause necrosis of cells…obvii)

Causes UTI infections (or so they think, “they” aren’t really sure)

Question 23

Which rough strain is used to make a vaccine for coliform mastitis?

Answer 23

J5 strain. Works on other bacteria.