Related Experiment Videos
A model of acute infectious neonatal diarrhoea
Abstract:
Oral inoculation of neonatal MFI mice with enterotoxigenic strains of Escherichia coli that possessed the K99 or F41 antigen or both resulted in severe diarrhoea with high mortality. The diarrhoea was associated with increased fluid in the gut, greatly increased numbers of E. coli in gut homogenates and reduced weight gain compared to control animals. Further studies with strain B44 demonstrated greatly increased numbers of E. coli on the surface of the intestinal mucosa and haemo-concentration. The infection was transmissible between litter-mates. There was no evidence of invasion of the intestinal tissue of infected animals. Gnotobiotic Balb C mice and endotoxin-resistant mice were susceptible to oral inoculation with bovine enterotoxigenic E. coli strains, but neonatal rats were not susceptible to infection with enterotoxigenic E. coli strains B44 or 431. Porcine strains of E. coli that possessed K88 or 987P antigen did not infect neonatal MFI mice but an "atypical" porcine strain (431) which possessed both K99 and F41 antigens caused diarrhoea and a high mortality. The disease in neonatal mice resembled acute diarrhoea caused by these bacteria in other species, particularly the calf, and the model should be of value in assessing the efficacy of therapeutic agents.
Insights
Neonatal mice inoculated with enterotoxigenic Escherichia coli (E. coli) developed severe diarrhea and high mortality. This model effectively mimics bacterial diarrhea in other species, aiding therapeutic agent assessment.
Area of Science:
- Veterinary Medicine
- Microbiology
- Infectious Diseases
Background:
- Enterotoxigenic Escherichia coli (E. coli) causes significant morbidity and mortality in neonatal livestock.
- Understanding the pathogenesis and host susceptibility is crucial for developing effective treatments.
Purpose of the Study:
- To establish and characterize a neonatal mouse model for enterotoxigenic E. coli infection.
- To evaluate the susceptibility of different mouse strains and neonatal rats to specific E. coli strains.
Main Methods:
- Oral inoculation of neonatal MFI mice with enterotoxigenic E. coli strains possessing K99, F41, or both antigens.
- Assessment of clinical signs, mortality, gut fluid, E. coli colonization, weight gain, and intestinal tissue.
- Testing susceptibility in gnotobiotic mice, endotoxin-resistant mice, and neonatal rats.
Main Results:
- Infection led to severe diarrhea, high mortality, increased gut fluid, high E. coli counts, reduced weight gain, and hemoconcentration.
- E. coli colonized the intestinal mucosa without invading tissues.
- Neonatal rats were resistant, while gnotobiotic and endotoxin-resistant mice were susceptible to bovine E. coli strains.
Conclusions:
- Neonatal MFI mice are a suitable model for studying enterotoxigenic E. coli-induced diarrhea, mirroring disease in other species.
- The model is valuable for evaluating the efficacy of therapeutic interventions against E. coli infections.