Difference between revisions of "Escherichia coli"

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{{review}}
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<big><center>[[Enterobacteriaceae|'''BACK TO ENTEROBACTERIACEAE''']]</center></big>
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<big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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<big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
 +
 
 +
 
 +
* [[Intestines - Inflammatory Bowel Disease And Related Conditions#Histiocytic Ulcerative Colitis|Histiocytic ulcerative colitis]] in the dog and cat.
 +
 
 +
* Causes [[Peritoneal cavity - inflammatory#In dogs|peritonitis in dogs]] and [[Peritoneal cavity - inflammatory#In pigs|peritonitis in pigs]]
 +
* In [[Bones - inflammatory#Osteomyelitis|osteomyelitis]]
 +
*In neonatal [[Joints - inflammatory#In Cattle|polyarthritis of calves]]
 +
*In [[Joints - inflammatory#In Horses|arthritis of horses]]
  
 
===''Eschericia coli'' (''E. coli'') overview===
 
===''Eschericia coli'' (''E. coli'') overview===
[[File:Ecoli.jpg|200px|right]]
+
 
 
*Member of ''Enterobacteriacae'' family of Gram-negative bacilli
 
*Member of ''Enterobacteriacae'' family of Gram-negative bacilli
*'''Facultative anaerobe'''
+
*Facultative anaerobe
 
*One of predominant bacterial species in colonic flora
 
*One of predominant bacterial species in colonic flora
 
*Colonisation of intestinal tract from environmental sources shortly after birth
 
*Colonisation of intestinal tract from environmental sources shortly after birth
 
*Abundant in the environment
 
*Abundant in the environment
 
*Most strains have low virulence
 
*Most strains have low virulence
*Found in many non-specific, endogenous infections, eg. wound infections, upper respiratory tract infections, infections of the urinary tract, mammary glands and uterus and septicaemia
+
*Found in many non-specific, endogenous infections, eg. wound infections and upper respiratory tract infections and septicaemia
*An enteropathogen, causing neonatal diarrhoea in young animals and enteric colibacillosis
+
*Also and enteropathogen
*Enterotoxigenic ''E. coli'' is the most common cause of diarrhoea in calves, lambs and pigs
 
 
*Pathogenic strains possess virulence factors allowing colonisation of mucosal surfaces
 
*Pathogenic strains possess virulence factors allowing colonisation of mucosal surfaces
  
Line 18: Line 27:
  
 
*Usually motile with flagella and fimbriae
 
*Usually motile with flagella and fimbriae
*'''Oxidase negative''' (do not possess cytochrome C oxidase)
+
*Oxidase negative (do not possess cytochrome C oxidase)
*Grow on '''MacConkey agar''' (in presence of bile salts), producing pink colonies
+
*Grow on MacConkey agar (in presence of bile salts), producing pink colonies
*'''Haemolytic activity'' on blood agar characteristic of certain strains
+
*Haemolytic activity on blood agar characteristic of certain strains
*'''Lactose fermenter'''
+
*Lactose fermenter
*Reduce nitrates to nitrites and ferment glucose to produce acid and gas
+
*Reduce nitrates to nitrits and ferment glucose to produce acid and gas
*Possess a lipopolysaccharide ('''O''') antigen, a flagellate ('''H''') antigen, polysaccharide capsule ('''K''') antigens and fimbrial ('''F''') antigens
+
*Possess a lipolysaccharide (O) antigen, a flagellate (H) antigen, polysaccharide capsule (K) antigens and fimbrial (F) antigens
 
*Epidemiological typing of ''E. coli'' uses antigen combinations, eg. O125:K12:H42
 
*Epidemiological typing of ''E. coli'' uses antigen combinations, eg. O125:K12:H42
  
Line 29: Line 38:
 
===Pathogenesis===
 
===Pathogenesis===
  
*<u>Virulence factors</u> include capsules, endotoxin, enterotoxins and colonisation factors
+
*Virulence factors include capsules, endotoxin, enterotoxins and colonisation factors
 
*Capsular polysaccharides produced by some strains prevent phagocytosis and interfere with complement
 
*Capsular polysaccharides produced by some strains prevent phagocytosis and interfere with complement
 
*Endotoxin is a lipolysaccharide component of the cell wall of Gram-negative bacteria, composed of lipid A, a core polysaccharide and various side chains
 
*Endotoxin is a lipolysaccharide component of the cell wall of Gram-negative bacteria, composed of lipid A, a core polysaccharide and various side chains
*'''Endotoxin''' is realeased when bacteria die, and causes endothelial damage leading to [[Disseminated Intravascular Coagulation|'''disseminated intravascular coagulation''']] and '''endotoxic shock'''; it is also a '''pyrogen'''
+
*Endotoxin is realeased when bacteria die, and causes endothelial damage leading to disseminated intravascular coagulation and endotoxic shock; it is also a pyrogen
*Enterotoxins, verotoxins and cytotoxic necrotising factors produced by many pathogenic ''E. coli''; these produce cell damage at their site of action
+
*
*'''Alpha-haemolysin''' may increase iron availability for invading organisms
 
*'''Siderophores''' are made by certain pathogenic strains, and are responsible for iron aquisition; they include aerobactin and enterobactin
 
  
==Extra-intestinal infection==
+
===Extra-intestinal infection===
  
 
*Soft tissue infections in adult animals
 
*Soft tissue infections in adult animals
 +
*Most common organism infecting urinary tract
 +
*Causes pyometra in the dog and cat and pyelonephritis
 +
*Acute mastitis in lactating animals
 
*Pathogenesis:
 
*Pathogenesis:
 
**Produces an alpha-haemolysin which may be cytotoxic
 
**Produces an alpha-haemolysin which may be cytotoxic
Line 47: Line 57:
 
**May enter blood to cause septicaemia
 
**May enter blood to cause septicaemia
 
*Clinical infections:
 
*Clinical infections:
**'''Urogenital tract infections'''
+
**Avian [[Intestines - Catarrhal Enteritis#Colibacillosis|colibacillosis]]:  
***Most common organism infecting urinary tract
+
***Septicaemia in newly-hatched chickens
***Ascending infections of urinary tract
+
***Infection enters via faecal contamination of the egg surface or via the ovary of the hen
***Causes pyometra in the dog and cat and [[Pyelonephritis|pyelonephritis]]
+
***Infection enters via the respiratory tract
***Cystitis in the bitch
+
***A bacteraemia develops
***Prostatitis in dogs via opportunistic infection
+
***Acute colisepticaemia, subacute fibrinopurulent serositis or chronic granulomatous disease of the viscera
***Colonisation of mucosa aided by fimbriae
+
***Occurs in older birds via inhalation of ''E. coli'' in dust; respiratory infection spreads to the blood to cause acute colisepticaemia
**'''Mastitis'''
+
***Airsacculitis, pericarditis and perihepatitis during acute phase
***Opportunistic infection of mammary glands of sows and cows
+
***Often secondary to virus or mycoplamsa infection or environmental stress
***Endotoxaemia in the acute form often fatal
+
**Colisepticaemia:
***Death within 24-48 hours during peracute disease
 
***Animals depressed with sunken eyes
 
**[[Colibacillosis|'''Colibacillosis''']]:  
 
***Avian:
 
****Septicaemia in newly-hatched chickens
 
****Infection enters via faecal contamination of the egg surface or via the ovary of the hen
 
****Infection enters via the respiratory tract
 
****A bacteraemia develops
 
****Acute colisepticaemia, subacute fibrinopurulent serositis or chronic granulomatous disease of the viscera
 
****Occurs in older birds via inhalation of ''E. coli'' in dust; respiratory infection spreads to the blood to cause acute colisepticaemia
 
****Airsacculitis, pericarditis and perihepatitis during acute phase
 
****Often secondary to virus or [[:Category:Mycoplasmas|''mycoplasma'']] infection or environmental stress
 
**'''Colisepticaemia''':
 
 
***Systemic disease in young calves, piglets, foals, lambs
 
***Systemic disease in young calves, piglets, foals, lambs
 
***Penetration of intestinal mucosa and entrance into the blood
 
***Penetration of intestinal mucosa and entrance into the blood
Line 75: Line 72:
 
***Virulence related to adhesive properties, complement resistance and ability for iron aquisition
 
***Virulence related to adhesive properties, complement resistance and ability for iron aquisition
 
***Ammonia, dust, viral infections and temperature changes enhance likelihood of disease
 
***Ammonia, dust, viral infections and temperature changes enhance likelihood of disease
**[[Oedema Disease|'''Oedema disease of pigs''']]:
 
  
**'''Watery mouth of lambs''':
+
===Intestinal disease===
***Affects lambs under three days old
 
***Lack of colostrum allows collonisation and overgrowth of ''E. coli'' in the small intestine
 
***Systemic invasion by ''E. coli''
 
***Absorption of endotoxin leads to death
 
***Severe depression, anorexia, salivation and abdominal distension
 
***Morbidity and mortality high
 
** [[Inflammatory Bowel Disease#Histiocytic Ulcerative Colitis|Histiocytic ulcerative colitis]] in the dog and cat.
 
** Causes [[Peritonitis - Cats and Dogs|peritonitis in dogs]] and [[Peritonitis#In pigs|peritonitis in pigs]]
 
**Found in [[Osteomyelitis|osteomyelitis]]
 
**Associated with neonatal [[Infectious Arthritis#In Cattle|polyarthritis of calves]]
 
**In [[Deep Pyoderma|deep pyoderma]]
 
**Found in [[Infectious Arthritis#In Horses|arthritis of horses]]
 
 
 
==Intestinal infection==
 
  
 
*''E. coli'' is part of the flora of the large intestine, but is not usually found in the small intestine
 
*''E. coli'' is part of the flora of the large intestine, but is not usually found in the small intestine
 
*Some strains possess fimbrae which attach the bacteria to the small intestinal epithelium of particular animal species
 
*Some strains possess fimbrae which attach the bacteria to the small intestinal epithelium of particular animal species
*''E. coli'' may cause diarrhoea via attaching and effacing lesions, where bacteria adhere intimately to the enterocyte, and cause localised effacement of the brush border microvilli; the epithelial erosion causes [[Haemorrhage#Dysentery|dysentery]]
+
*K88 (F4) is associated with adhesion to the small intestinal mucosa of pigs
 
+
*K99 (F5) associated with adhesion in pigs and cattle (these possess certain fimbrae, and are now renamed F antigens)
 
+
*The fimbrae are encoded by plasmids
*'''Enterotoxigenic ''E. coli'' (ETEC)''':
+
*''E. coli'' may cause diarrhoea via attaching and efacing lesions, where bacteria adhere intimately to the enterocyte, and cause localised effacement of the brush border microvilli
**General:
+
*Enterotoxigenic ''E. coli'':
*** Contributes to [[Calf Diarrhoea, Undifferentiated Neonatal|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves, also known as enteric colibacillosis
+
** Contributes to [[Intestines - Catarrhal Enteritis#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves
***Causes scours in pigs, calves and lambs
+
**Causes scours in pigs and calves
***'Traveller's diarrhoea' in humans
+
**'Traveller's diarrhoea' in humans
**Pathogenesis:
+
**These strains carry a plasmid which encodes an enterotoxin
***Oral infection, intestinal colonisation and toxin production
+
**Two types of enterotoxin: heat-labile (LT) and heat-stable (ST) toxins
***Fimbrial antigen or colonisation factor antigens (CFAs)determine species specificity
+
**The plasmids which produce these toxins are responsible for the pathogenicity of these strains
***Fimbrial adhesins allow bacteria to attach to mucosal surfacesin the small intestine and lower urinary tract; this prevents expulsion by peristalsis and flushing of urine
+
**Fimbrial antigen or colonisation factor antigens (CFAs)determine species specificity
***K88 (F4) is associated with adhesion to the small intestinal mucosa of pigs
+
**Fimbrial adhesins allow bacteria to attach to mucosal surfacesin the small intestine and lower urinary tract; this prevents expulsion by peristalsis and flushing of urine
***K99 (F5) associated with adhesion in pigs and cattle (these fimbrial adhesins were originally thought to be capsular (K) antigens)
+
**LT is an oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
***The '''fimbriae are encoded by plasmids'''
+
**It attaches to the brush border of the epithelial cells of the small intestine
***These strains carry a plasmid which encodes an enterotoxin
+
**LT causes ADP-ribosylation of the stimulatory subunit of guanine nucleotide binding proteins of the adenylate cyclase complex in eukaryotic cell membranes
***Two types of '''enterotoxin: heat-labile (LT) and heat-stable (ST) toxins'''
+
**This causes irreversible activation of adenylate cyclase in target cells
***The '''plasmids''' which produce these toxins are '''responsible for the pathogenicity''' of these strains
+
**This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
****'''LT'''
+
**The gut becomes distended with fluid and a [[Intestines - diarrhoea#Secretory Diarrhoeas|secretory diarrhoea]] which lasts several days results
*****An oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
+
**LT is antigenic
*****It attaches to the brush border of the epithelial cells of the small intestine
+
**Immunity is developed via production of antibody to LT protein and fimbrial antigen
*****Causes ADP-ribosylation of the stimulatory subunit of guanine nucleotide binding proteins of the adenylate cyclase complex in eukaryotic cell membranes
+
**Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
*****This causes irreversible activation of adenylate cyclase in target cells
+
**ST is not immunogenic; it is small, with only 19 amino acids
*****This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
+
**ST activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
****'''ST'''
+
*Enteropathogenic ''E. coli'':
*****Activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
+
**Possess ''E. coli'' adherencefactor plasmid
**Clinical signs:
+
**Cause attching and effacing lesions in the gut
***The gut becomes distended with fluid and a [[Diarrhoea#Secretory Diarrhoeas|secretory diarrhoea]] which lasts several days results
+
*Enteroinvasive ''E. coli''
***Watery diarrhoea, dehydration, acidosis, death
+
**Dysentry-like strains
**Immunity:
+
**Invade epithelial cells by inducing endocytosis  
***LT is antigenic
+
**Traverse gut wall to lamina propria
***Immunity is developed via production of antibody to LT protein and fimbrial antigen
+
*Enterohaemorrhagic ''E. coli'':
***Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
 
***ST is not immunogenic; it is small, with only 19 amino acids
 
 
 
 
 
*'''Enteropathogenic ''E. coli'' (EPEC)''':
 
**Attaching and effacing strains of ''E. coli''
 
**Attach to small intestinal epithelial cells and cause necrosis of enterocytes and stunting and fusion of villi
 
**Possess ''E. coli'' adherence factor plasmid
 
**An adhesin, intimin is required for attachment to enterocytes
 
**Secrete signalling proteins that activate a tyrosine kinase, causing rearrangement of cytoskeletal proteins and effacement of microvilli
 
**Intracellular calcium levels increase and production of protein kinase C causes loss of chloride ions and water from the intestinal epithelial cells
 
**Diarrhoea results
 
 
 
 
 
*'''Enteroinvasive ''E. coli''''':
 
**Cause colisepticaemia in calves during their first week of life; occasionally in lambs, piglets and puppies
 
**Infection via ingestion or umbilicus; inadequate colostrum increases susceptibility
 
**Invade epithelial cells of small intestine by inducing endocytosis  
 
**Traverse gut wall to lamina propria and enter lymphatics
 
**Resistant to complement-mediated killing
 
**Bacteraemia or septicaemia and endotoxaemia
 
**Widespread petechial haemorrhages of organs and serosa
 
**Abscesses, pneumonia in long term
 
**Death occurs in absense of treatment
 
 
 
 
 
*'''Enterohaemorrhagic ''E. coli''''':
 
 
**Possibly carried by cattle
 
**Possibly carried by cattle
 
**Produce shiga-like toxin, a vero toxin
 
**Produce shiga-like toxin, a vero toxin
**Plasmid-coded fimbriae important for virulence
 
**Intimin produced allowing intimate attachment to intestinal epithelial cells
 
**Strains do not product LT or ST and are not enteroinvasive
 
 
**Attaching and effacing lesions, unrelated to toxin production
 
**Attaching and effacing lesions, unrelated to toxin production
**[[Disseminated Intravascular Coagulation|Disseminated intravascular coagulation]] and thrombus formation  
+
**Disseminated intravascular coagulation and thrombus formation  
 
**''E. coli'' O157:H7 causes haemorrhagic collitis-haemolytic uraemic syndrome in humans
 
**''E. coli'' O157:H7 causes haemorrhagic collitis-haemolytic uraemic syndrome in humans
 +
*Enteroaggretative ''E. coli'':
  
 +
*Oedema disease of pigs:
 +
**Associated with oedema disease toxin-producing strains of ''E. coli''
 +
**Verotoxin released in the small intestine and carried in the bloodstream
 +
*Haemorrhagic gastroenteritis:
  
*'''Cytotoxin necrotising factor-producing ''E. coli'''''
+
*Watery mouth of lambs:
**Infrequently cause diarrhoea in calves, pigs and humans
+
**Lack of colostrum allows collonisation and overgrowth of ''E. coli'' in the small intestine
**Important virulence factors include toxin and fimbriae
+
**Absorption of endotoxin leads to death
 
 
==in cattle==
 
 
 
 
 
*Neonatal polyarthritis:
 
 
 
**[[Escherichia coli|'''''Coliforms''''']]
 
***Localises in joints and meninges in severe non-fatal neonatal colibacillosis
 
***May remain as chronic arthritis in larger joints
 
 
 
[[Category:Enterobacteriaceae]]
 
[[Category:To_Do_-_Bacteria]]
 

Revision as of 17:38, 23 December 2007

BACK TO ENTEROBACTERIACEAE
BACK TO BACTERIA
BACK TO INFECTIOUS AGENTS AND PARASITES


Eschericia coli (E. coli) overview

  • Member of Enterobacteriacae family of Gram-negative bacilli
  • Facultative anaerobe
  • One of predominant bacterial species in colonic flora
  • Colonisation of intestinal tract from environmental sources shortly after birth
  • Abundant in the environment
  • Most strains have low virulence
  • Found in many non-specific, endogenous infections, eg. wound infections and upper respiratory tract infections and septicaemia
  • Also and enteropathogen
  • Pathogenic strains possess virulence factors allowing colonisation of mucosal surfaces


E. coli characteristics

  • Usually motile with flagella and fimbriae
  • Oxidase negative (do not possess cytochrome C oxidase)
  • Grow on MacConkey agar (in presence of bile salts), producing pink colonies
  • Haemolytic activity on blood agar characteristic of certain strains
  • Lactose fermenter
  • Reduce nitrates to nitrits and ferment glucose to produce acid and gas
  • Possess a lipolysaccharide (O) antigen, a flagellate (H) antigen, polysaccharide capsule (K) antigens and fimbrial (F) antigens
  • Epidemiological typing of E. coli uses antigen combinations, eg. O125:K12:H42


Pathogenesis

  • Virulence factors include capsules, endotoxin, enterotoxins and colonisation factors
  • Capsular polysaccharides produced by some strains prevent phagocytosis and interfere with complement
  • Endotoxin is a lipolysaccharide component of the cell wall of Gram-negative bacteria, composed of lipid A, a core polysaccharide and various side chains
  • Endotoxin is realeased when bacteria die, and causes endothelial damage leading to disseminated intravascular coagulation and endotoxic shock; it is also a pyrogen

Extra-intestinal infection

  • Soft tissue infections in adult animals
  • Most common organism infecting urinary tract
  • Causes pyometra in the dog and cat and pyelonephritis
  • Acute mastitis in lactating animals
  • Pathogenesis:
    • Produces an alpha-haemolysin which may be cytotoxic
    • Iron aquisition system
    • K antigens prevent phagocytosis or mimic host antigens and resist complement
    • Fimbriae permit adhesion to mucosal surfaces
    • May enter blood to cause septicaemia
  • Clinical infections:
    • Avian colibacillosis:
      • Septicaemia in newly-hatched chickens
      • Infection enters via faecal contamination of the egg surface or via the ovary of the hen
      • Infection enters via the respiratory tract
      • A bacteraemia develops
      • Acute colisepticaemia, subacute fibrinopurulent serositis or chronic granulomatous disease of the viscera
      • Occurs in older birds via inhalation of E. coli in dust; respiratory infection spreads to the blood to cause acute colisepticaemia
      • Airsacculitis, pericarditis and perihepatitis during acute phase
      • Often secondary to virus or mycoplamsa infection or environmental stress
    • Colisepticaemia:
      • Systemic disease in young calves, piglets, foals, lambs
      • Penetration of intestinal mucosa and entrance into the blood
      • Invasive strains survive the host defences
      • Virulence related to adhesive properties, complement resistance and ability for iron aquisition
      • Ammonia, dust, viral infections and temperature changes enhance likelihood of disease

Intestinal disease

  • E. coli is part of the flora of the large intestine, but is not usually found in the small intestine
  • Some strains possess fimbrae which attach the bacteria to the small intestinal epithelium of particular animal species
  • K88 (F4) is associated with adhesion to the small intestinal mucosa of pigs
  • K99 (F5) associated with adhesion in pigs and cattle (these possess certain fimbrae, and are now renamed F antigens)
  • The fimbrae are encoded by plasmids
  • E. coli may cause diarrhoea via attaching and efacing lesions, where bacteria adhere intimately to the enterocyte, and cause localised effacement of the brush border microvilli
  • Enterotoxigenic E. coli:
    • Contributes to undifferentiated neonatal calf diarrhoea, a mixed viral enteritis in calves
    • Causes scours in pigs and calves
    • 'Traveller's diarrhoea' in humans
    • These strains carry a plasmid which encodes an enterotoxin
    • Two types of enterotoxin: heat-labile (LT) and heat-stable (ST) toxins
    • The plasmids which produce these toxins are responsible for the pathogenicity of these strains
    • Fimbrial antigen or colonisation factor antigens (CFAs)determine species specificity
    • Fimbrial adhesins allow bacteria to attach to mucosal surfacesin the small intestine and lower urinary tract; this prevents expulsion by peristalsis and flushing of urine
    • LT is an oligometric toxin composed of an enzymatically-active A subunit (30KDa; 2 fragments - A1 and A2) and 5 identical B subunits (12KDa) forming the binding portion (B oligomer)
    • It attaches to the brush border of the epithelial cells of the small intestine
    • LT causes ADP-ribosylation of the stimulatory subunit of guanine nucleotide binding proteins of the adenylate cyclase complex in eukaryotic cell membranes
    • This causes irreversible activation of adenylate cyclase in target cells
    • This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
    • The gut becomes distended with fluid and a secretory diarrhoea which lasts several days results
    • LT is antigenic
    • Immunity is developed via production of antibody to LT protein and fimbrial antigen
    • Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
    • ST is not immunogenic; it is small, with only 19 amino acids
    • ST activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
  • Enteropathogenic E. coli:
    • Possess E. coli adherencefactor plasmid
    • Cause attching and effacing lesions in the gut
  • Enteroinvasive E. coli
    • Dysentry-like strains
    • Invade epithelial cells by inducing endocytosis
    • Traverse gut wall to lamina propria
  • Enterohaemorrhagic E. coli:
    • Possibly carried by cattle
    • Produce shiga-like toxin, a vero toxin
    • Attaching and effacing lesions, unrelated to toxin production
    • Disseminated intravascular coagulation and thrombus formation
    • E. coli O157:H7 causes haemorrhagic collitis-haemolytic uraemic syndrome in humans
  • Enteroaggretative E. coli:
  • Oedema disease of pigs:
    • Associated with oedema disease toxin-producing strains of E. coli
    • Verotoxin released in the small intestine and carried in the bloodstream
  • Haemorrhagic gastroenteritis:
  • Watery mouth of lambs:
    • Lack of colostrum allows collonisation and overgrowth of E. coli in the small intestine
    • Absorption of endotoxin leads to death