Enterobacteriaceae, Escherichia coli (E.coli) - Gutierrez Flashcards
What bacteria type can grow on MacConkey agar?
Gram neg
Virulence factors in Gram negative bacteria?
- LPS endotoxin (Lipid A)
- Fimbriae
- Capsule
- Flagella
- Toxins
- Siderophores
- Adhesions
What are the fecal coliforms?
- Escherichia coli
- Enterobacter spp.
- Klebsiella spp
- Citrobacter spp.
_______ refer to enterobacteriaceae that ferment lactose
Coliforms
Major pathogenic enterobacteriaceae spp that infect animals?
- Yersinia
- E. coli
- Salmonella
Opportunistic enterobacteriaceae spp?
- Klebsiella
- Proteus
Which part of the LPS from gram negative bacteria is known as an endotoxin?
Lipid A
Most strains of E.coli are ___________
Commensals
How does an animal acquire E.coli?
Rapid acquisition from the environment
The concentration of E. coli is higher in which part of the body?
Large intestines
E. coli vs the environment?
- Survives well in environment but usually does not multiply
What are the intestinal pathogenic E.coli?
- ETEC: Enterotoxigenic E.coli
- EPEC: Enteropathogenic E.coli
- EHEC: Enterohemorragic E.coli
Virulence factors associated with ETEC: Enterotoxigenic E.coli?
- Enterotoxins
- Adhesions
ETEC: Enterotoxigenic E.coli infects what animal species?
- Calves
- Piglets
- Lambs
CS associated with ETEC: Enterotoxigenic E.coli?
severe watery diarrhea, dehydration, metabolic acidosis, death
When can CS be seen with ETEC: Enterotoxigenic E.coli ?
First few days after birth in calves, lambs, and piglets
Disease in piglets caused by ETEC: Enterotoxigenic E.coli?
- Neonatal diarrhea
- Post weaning disease
ETEC in piglets depends on?
The equilibrium between maternal immunity and infection pressure
How can piglets become more susceptible to ETEC?
- Low birth weight
- Too many piglets per sow
- Low hygiene
- Other infections
In newborns, when can infection with ETEC begin?
1st few days after birth
Lipid A endotoxin results in what clinical sign?
Fever
True or False: Bacteria forming pedestals is a common route of EPEC
TRUE
What is the most important pathogroup of E.coli in large animals?
ETEC
Post weaning diarrhea in piglets from ETEC can result in ____________
Death due to shock (LPS)
How to prevent ETEC in young livestock?
Keep infection pressure low and maternal immunity high
__________ is the main cause of diarrhea in young livestock within a few days of age
ETEC
Edema disease in pigs is associated with what toxin?
Stx2e exotoxin (Shiga toxin)
What receptors are expressed in ETEC infected piglets with post weaning diarrhea?
- F4
- F18
What receptors are expressed in ETEC infected piglets with neonatal diarrhea?
- F4
- F41
- F5
ETEC in bovines and ovines results in ___________
- Neonatal diarrhea
- Neonatal diarrhea + septicemia
Neonatal diarrhea in bovines infected with ETEC is caused by what toxins?
STa and EAST1
Neonatal diarrhea in bovines infected with ETEC express what receptors?
- F5
- F41
A farmer is having problems with young calves having diarrhea despite claiming they are vaccinated for E. coli. What might be the problem?
Vaccine is for targeting F4 and F18 receptors instead of F5
Neonatal diarrhea AND septicemia in bovines infected with ETEC express what receptors?
F17+
What makes calves susceptible to being infected with ETEC?
- Getting colostrum too late
- Not enough colostrum
- Early infection or high load of infection
What antibody type could be administered to treat ETEC or EPEC in livestock?
Antibodies against lipid A
(Anti-lipid A)
EPEC is most pathogenic in which of the following species?
A. Dogs
B. Calves
C. Rabbits
D. Piglets
C. Rabbits
(also called RPEC in rabbits)
Piglets are more at risk for which of the following: ETEC or EPEC
ETEC
_______ toxin is produced in the intestine but is absorbed and carried in the bloodstream, leading to damage of blood capillaries and increased fluid loss. This is caused by _______ strain of E.coli
Shiga, EHEC/STEC/VTEC
What receptor is expressed in edema disease of pigs?
F18
A piglet showing neurological signs with no diarrhea. What is your top differential?
EHEC/STEC/VTEC - Edema disease of pigs
How do you treat EHEC?
- Fasting to eliminate toxin + increase peristalsis
- Antibiotics
- Treat the unaffected animals too!!
How can EHEC be prevented in pigs?
- Reduce stress
- Vaccinate
- Feed composition
- Selection of F18r- animals (they don’t have this receptor so they can’t get infected)
Some pigs on the farm have been infected with EHEC and are showing symptoms, but half of the pig population tested negative and are showing no clinical signs. How can this be?
Some pigs can be F18r-
They do not express the receptor needed to cause EHEC/edema disease in pigs
What E.coli spp infects cattle and is of zoonotic importance?
EHEC/STEC/VTEC
I ate a medium rare steak and now have bloody diarrhea. What E.coli spp am I most likely infected with?
EHEC/STEC/VTEC
HUS is defined by the triad:
- Acute renal failure
- Thrombocytopenia
- Hemolytic anemia
Virulence factors associated with UPEC?
- P fimbriae (pap genes)
- Mannose- resistant adhesins
- Type 1 fimbria (mannose receptor)
- Hemolysin (HlyA)
- Aerobactin (siderophore)
_______ is the most important pathogen in UTIs of warm blooded animals
UPEC
UPEC is more common in which of the following species? Dogs or Cats
Dogs
What E.coli spp affects mainly adult pigs?
UPEC
Symptoms associated with UPEC?
- Hematuria
- Vaginal exudate
- Anorexia
What do you do if a pig tests positive for UPEC?
Cull pig, fertility problems
UPEC in dogs can result in:
- Cystitis
- Urethritis
- Pyelonephritis
- Prostatitis
- Pyometra
What E.coli spp causes watery mouth disease?
SEPEC: Septicemic E.coli
in shoats
Invasion of SEPEC in bovines is through __________
Intestinal epithelium or the umbilicus
Which E.coli spp is excreted in nasal secretions and urine of bovines?
SEPEC: Septicemic E.coli
Are neonate or suckling pigs more susceptible to SEPEC?
Neonates
How does SEPEC avoid phagocytosis?
- Capsule is resistant to phagocytosis
- P fimbriae and O antigens
- Type 1 fimbriae promotes adhesion
Virulence factors associated with NTEC?
- Cytotoxic necrotizing factors (CNF1-3)
- Cytolethal distending toxin (CDT)
- F17, Afa, aerobactin
MPEC in bovines causes __________
coliform mastitis
Which species of E.coli has no known virulence factors?
MPEC
What animal species can be infected with MPEC?
Bovines and pigs
_________ is a major pathogen in the poultry industry
APEC: avian pathogenic E.coli
Clinical manifestations associated with APEC? (6)
- Neonatal colibacillosis
- Respiratory colibacillosis
- Egg yolk peritonitis
- Scabby hip/necrotic dermatitis
- Swollen head syndrome
- Coligranuloma
How are cows infected with MPEC?
fecal contamination of udders
Post partum dysgalactiae syndrome occurs in _______ species of animals and is caused by _______ spp of E.coli
Pigs, MPEC
CS associated with MPEC in pigs?
- Reluctant to nurse
- Constipation
- Thick vaginal discharge
- Increased resp rate
What can be seen in poultry with neonatal colibacilosis?
- Enlarged liver and spleen
- Fluid in body cavities
- Drooping of head
- Speticemia - death
What can be seen in poultry with respiratory colibacilosis?
- Thickened air sacs with caseous exudate on resp surface
- Edema
- Airsacculitis
- Perihepatitis and/or pericarditis
- Septicemia - death
- Fever
What spp of E.coli and clinical manifestation can result in a cooked egg appearance on necropsy of poultry?
APEC, egg yolk peritonitis
What can be seen in poultry with scabby hip/necrotic dermatitis?
- Loss of feathers
- Dead birds decompose quickly
- Discoloration/ thickened inflamed skin
Swollen head syndrome is caused by what spp of E.coli?
APEC
What can be seen in poultry with swollen head syndrome?
- Edema/swelling over the eyes
- Begins as acute rhinitis
_________ is a clinical manifestation in older birds infected with APEC
Coligranuloma
What can be seen in poultry with coligranuloma?
- Granulomas in the liver, cecum, duodenum, mesentery, and serosal surfaces
- lingering mortality