A rat model for dose-response relationships of Salmonella Enteritidis infection.
OBJECTIVE
To develop an animal model to study dose-response relationships of enteropathogenic bacteria.


RESULTS
Adult, male Wistar Unilever rats were exposed orally to different doses of Salmonella enterica serovar Enteritidis after overnight starvation and neutralization of gastric acid by sodium bicarbonate. The spleen was the most sensitive and reproducible organ for detection of dose-dependent systemic infection. Illness was only observed in animals exposed to doses of 10(8) cfu or more. At lower doses, histopathological changes in the gastro-intestinal tract were observed, but these were not accompanied by illness. Marked changes in numbers and types of white blood cells, as well as delayed-type hyperresponsiveness, indicated a strong, dose-dependent cellular immune response to Salm. Enteritidis.


CONCLUSIONS
The rat model is a sensitive and reproducible tool for studying the effects of oral exposure to Salm. Enteritidis over a wide dose range.


CONCLUSIONS
The rat model allows controlled quantification of different factors related to the host, pathogen and food matrix on initial stages of infection by food-borne bacterial pathogens.
Havelaar
A H
AH
Microbiological Laboratory for Health Protection, National Institute of Public Health and the Environment, Bilthoven, the Netherlands.
Garssen
J
J
Takumi
K
K
Koedam
M A
MA
Dufrenne
J B
JB
van Leusden
F M
FM
de La Fonteyne
L
L
Bousema
J T
JT
Vos
J G
JG
D000284:Administration, Oral; D000818:Animals; D004195:Disease Models, Animal; D005215:Fasting; D005243:Feces / Q000382:microbiology; D005744:Gastric Acid / Q000378:metabolism; D005745:Gastric Acidity Determination; D006863:Hydrogen-Ion Concentration; D006968:Hypersensitivity, Delayed / Q000276:immunology / Q000382:microbiology; D007958:Leukocyte Count; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000382:microbiology* / Q000503:physiopathology*; D012477:Salmonella enteritidis / Q000502:physiology*; D017693:Sodium Bicarbonate / Q000378:metabolism; D013154:Spleen / Q000382:microbiology
D017693:Sodium Bicarbonate