Entero: E. coli (Ex2) Flashcards
Where does Enterobacteriacae normally reside?
What are the benefits of it being there?
- Resides in the GI tract
- Microbial antagonism
- Breakdown and absorption of food
- Waste processing
- Vitamin K production
General features of Enterobacteriacae
gram, oxygen requirements, shape, oxidase
- Gram negative
- facultative anaerobe
- rods or coccobacilli
- oxidase negative
What are Coliform Bacteria?
Name the three included
- Lactose positive bacteria
- E. coli
- Klehsiella
- Enterobacter
General features of Escherichia coli
lactose, oxidase, motility, shape
- lactose positive
- oxidase negative
- motile
- rods
Virulence Factors of E. coli
- capsule
- fimbrial and non-fimbrial adhesions
- endotoxin (LPS)
- enterotoxins
- cytotoxins
- siderophores
What do these stand for? ETEC EHEC VTEC/STEC EPEC RPEC APEC NTEC
ETEC - enterotoxigenic EHEC - enterohemorrhagic VTEC/STEC - verotoxigenic/shiga-like toxic EPEC - enteropathic RPEC - rabbit pathogenic APEC - avian pathogenic NTEC - nectrotoxigenic
General Features of ETEC in pigs
symptoms, age affected, adhesion factors, enterotoxins
- watery diarrhea
- neonatal, weanlings
- adhesion factors: F4, F5, F6, F18, F41
- enterotoxins: LT, Sta, Stb, EAST1
Adhesion factors of ETEC in pigs
F4 - on plasmids, specific receptors, mannose resistant, genes expressed at body temp, solely in pigs, neonates to weanlings
F5 - on plasmids, in pigs and bovines, mannose resistant, expression temp dependent, in young animals
F6 - extrachromosomal, neonatal
F41 - chromosomal, mannose resistant, pigs and bovines, freq with F5, rare, neonatal
Describe LT enterotoxin in ETEC in pigs
- heat labile
- high molecular weight
- strong antigen
- Na absorption, Cl and HCO3 secretion
- activation of adenlyate cyclase
Describe the heat stable enterotoxins in ETEC in pigs
- low molecular weight
- little antigen
- Sta: activation of guanylate cyclase, Na absorption, Cl and HCO3 secretion
- Stb: prostaglandin E2, secretion of water and electrolytes, stimulation of 5-H secretion
- EAST1: closely related to Sta
Characteristics present at each age (neonatal, neonatal till 4 wks, weanling) in ETEC in pigs
(adhesion, enterotoxins, hemo/non)
Neonatal: F5, F6, F41; Sta, Stb; non-hemolytic
Neonatal - 4 wks: F4; LT, Sta, STb, EAST1; hemolytic
Weanling: F4, F18; LT, Sta, Stb, EAST1; hemolytic
What are the causes of ETEC in pigs?
- increase infection pressure
- lowering of maternal immunity (MMA, first delivery, low birth weight, too many piglets)
- appearance of new type
What are the symptoms of ETEC in pigs?
- remain drinking
- smelly feces
- dehydration
- diarrhea
How do you diagnose ETEC in pigs?
- agglutination tests
- PCR
Treatment of ETEC in pigs
- hydration
- antimicrobials
Prevention of ETEC in pigs
- keep infection pressure low and maternal immunity high
- hygiene
- vaccination of sows
- selection of receptor free piglets
Virulence factors of VTEC in pigs
- adhesion in small bowel: F18
- exotoxin: VT2e or Stx2e: media necrosis
- endotoxin: acute mortality
What are the symptoms of VTEC in pigs?
- acute mortality in some
- diarrhea in some
- anorexia
- edema (hoarse voice, dyspnea, swollen eyelids, CNS)
- CNS signs
How do you treat VTEC in pig?
- fasting to eliminate toxin
- increases intestinal peristalsis
- antimicrobial therapy
How do you prevent VTEC in pigs?
- reduce stress
- feed restriction, increase fiber content, starter feed before weaning
- adaptation of intestinal flora (probiotics, organic acids, zinc oxide, antimicrobials, vaccination)
- selection of F18 receptor negative animals
What are the symptoms of UTI E. coli in pigs?
- anorexia
- hematuria
- vaginal exudate
- general malaise
What is MMA of PPDS?
What are the possible etiologies?
- Metritis-Mastitis-Agalactiae
- Post Partum Dysgalactiae Syndrome
- problem in milk production
- E: hereditary, hormonal, feed, infectious agents
What are the symptoms of ETEC in bovines?
What age is affected?
- watery diarrhea leading to dehydration
- less than 3 days old, neonates
Virulence factors of ETEC in bovines
- fimbriae (F5, F41, F17, CS31A)
- toxins (Sta and Stb)
