Susceptibility of Gastro-Intestinal Tract to Irritating Action of Salmonella Group of Food-Poisoning Bacteria.

Abstract

There is a bactericidal mechanism in the small intestine that causes the destruction of bacteria injected directly into the duodenum, or that pass through the stomach into the intestine. 1 , 2 , 3 , 4 Savage and White 5 have shown that certain types of “food-poisonings” can be caused by heat-stable toxic substances in B. enteritidis infected food material. Young dogs (3 to 6 months old) were fed meat and bread. The meat was ground up and mixed with equal amount of 1 per cent NaCl solution, autoclaved. Some samples were mixed with bread to proper consistency and fed as controls. B. enteritidis (5 strains obtained from Prof. E. O. Jordan) was inoculated in some of these meat flasks, incubated 24 hours, and stood at room temperature for 5 to 7 days before being mixed with bread and fed to the dogs. In the third experiment, the same B. enteritidis infected meat was placed in the boiling water for 45 minutes, bread added and fed as in other experiments. All food was warmed to 30° to 35° C. before feeding.

Cool or ordinary temperature room was 50° F. and 40 per cent relative humidity. Warm room was 98° F. and 70 per cent relative humidity; effective temperature was 91°. Windows and doors in both rooms were closed. Table I gives the results of gastric analysis on 44 dogs fed with the three above mentioned mixturles. These were acute experiments, dogs anesthetized 2 ½ hours after feeding.

Table II shows the relative distribution of B. prodigiosus in the gastro-intestinal tract 2 ½ hours after ingestion under the same conditions as the previous experiment. Six young dogs 4 months old of the same litter were used.