Model of sepsis (Caecal Ligation and Puncture) in rats caused by mixed and pure bacterial cultures and changes in white blood cell counts

The number of leucocytes and immunocompetent cells, was investigated during a clinical form of sepsis in rats. The experiments were carried out on 104 male rats, Wistar strain, of body weight 190 to 240 g. The rats were divided into four groups: three with 28 animals and one control group with 20 animals. The animals were killed 12, 24, 72 or 120 hours after surgical intervention. This consisted of caecal ligation and puncture (CLP), with inoculation of mixed bacteria or pure cultures of Escherichia coli or Staphylococcus aureus. They induced similar changes in the total leukocyte counts and percentages of different white blood cells. The significant leucopenia in the first half (early sepsis) of the examined period preceded significant leukosis in the rats with sepsis in the second half of the experiment (late sepsis). Also there were significant alterations in the numbers of granulocytes and agranulocytes. Neutrophilia and lymphopenia dominated during the whole period