EVALUATION OF THE EFFECT OF EXPERIMENTAL COW ENDOMETRITIS ON BACTERICIDAL CAPABILITY OF PHAGOCYTIZING CELLS ISOLATED FROM THE BLOOD AND UTERINE

Studies were undertaken to assess the bactericidal activity of phagocy tes isolated from blood and the uterine lumen of clinically healthy co ws after ovulation, and from cows in which endometritis was induced ex perimentally. Experiments were carried out on 28 clinically healthy co ws of the black and white lowland breed. Animals were aged 5 years and were used between the 2nd and 8th day after spontaneous ovulation. Co ws were divided into four groups. Group I comprised animals in which c ell-mediated type immune reaction was induced in the left uterine horn by intrauterine challenge with tuberculin. Cows in this group were in itially vaccinated with M. bovis via the intrauterine route. In group II, Arthus type immune reaction was induced by challenging immunized a nimals with C. fetus ssp. veneralis through intrauterine instillation. The non-specific inflammatory process was initiated in the uterus of animals in group III by one instillation of lipopolysaccharide from S. abortus equi. Animals in group IV were set as control and received a phosphate buffered saline instillation into the uterine lumen. The cel ls from the left uterine horn were washed out 6 h after induction. Neu trophils were isolated from blood samples collected from all animals w ithin the same time. The bacterial activity of cells from the uterine lumen and blood was assessed with the nitro-blue tetrazolium reduction test. Results are presented as increase in optical density resulting from a constant number of phagocytizing cells (Delta OD/10(6) cells). Induction of cell-mediated immune reaction or Arthus type immune react ion in the uterus significantly boosts the intracellular capability of uterine cells to kill bacteria through the oxidation system. Experime ntally induced non-specific endometritis weakens the bactericidal acti vity of uterine phagocytes, while peripheral blood phagocytes efficien tly kill the engulfed bacteria.