Effects of Food Borne Pathogens on the Internal Organs of Albino Rats (Rattus norvegicus)

Different bacterial and fungal species were isolated from ready-to-eat foods in six major cities in Ondo State, Nigeria. The pathogenicity testing was carried out using albino rats which were fed with food-borne pathogenic isolates. The feeding process was carried out for a period of two weeks, during which the weights and physical appearance of the rats under study were closely observed and recorded. The internal organs of experimental rats with special emphasis on heart, liver, kidney, small and large intestines were also used as case studies. Albino rats were fed with feed contaminated with microbial isolates of food origin. The organisms are Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis, Bacillus cereus and Salmonella typhi. The rats were grouped into seven categories with each containing two rats which were fed with a specific pathogen. The results for hematology test showed that infected rats had an increase in white blood cell count in relation to their PCV while the uninfected rats (control rats) had normal white blood cell counts in relation to their PCV. Histopathology tests showed that infected rats demonstrated hemorrhage destruction and aggregation of lymphoid cells in the livers and heart. Uninfected rats showed intact tissues in their livers and hearts. It can however be deduced that the effects of food-borne pathogens is cytolytic in the tissues and there is a geometric increase in white blood cells activated in response to invasion of food-borne pathogens.