Introduction: Bacterial translocation is defined as the passage of bacteria from intestinal tract to the extraintestinal organs such as the peritoneum and blood circulation. The aim of this study is to examine bacterial translocation (regarding type of bacteria and effect of time of obstruction on bacterial translocation) from intestinal lumen to the peritoneum and viscera in acute, simple mechanical, small bowel obstruction in rats. 

 Methods: In this cohort study, thirty female Wistar rats were divided into three groups with two subgroups, each sub-group containing 5 rats. The 1st group consisted of two sham-operated and non-operated control subgroups. The 2nd group was the IO-24 group, and the 3rd group was the IO-48 group in which the interval between producing intestinal obstruction and the second laparotomy was 24 h and 48 h respectively. Each subgroup was divided into two subgroups of partial and complete obstruction. The data was analyzed using Fisher’s exact test and K2 test in SPSS. 

 Results: The most common types of bacteria were E. coli in aerobic culturing and bacteroid in anaerobic culturing. However, as the time of obstruction increased, the pattern of bacterial translocation changed to anaerobic bacteria.

 Conclusions: Our study showed that with increased time of obstruction, pattern of bacterial translocation changed from aerobic to anaerobic. Enterococci were the most common type of bacteria in an aerobic group.