Effect of elective cesarean section on the incidence of subclinical endometritis in Belgian Blue cows

Over 95% of Belgian Blue (BB) cows deliver via elective cesarean section (CS). The aim of this study was to determine the effect of elective CS on the incidence of subclinical endometritis (SCE) using cytobrush (CB) and low-volume lavage (LVL) techniques and evaluate the sensitivity of both techniques in detecting SCE. Uteri of BB cows (n = 100) were collected from the slaughterhouse. Cytobrush samples followed by LVL cytology samples were collected from all uterine horns (n = 200). The samples collected by CB was rolled on a microscope slide while LVL samples were centrifuged, and the pelleted cells were then scattered over a microscope slide. In total, three hundred nucleated cells were identified and the proportion of polymorphonuclear (PMN%) to endometrial cells was assessed. The cut-off for SCE was set at ≥1% PMN. To compare the CS horn with its CS-free counterpart, linear (PMN%) and logistic regression (SCE positive versus SCE negative) modeling was performed. The PMN% in CB (0.34 ± 0.45%) samples was lower than in LVL (2.67 ± 0.45%) samples (p < 0.0001), suggesting LVL is a more sensitive technique than CB. The CS horn had no effect on the PMN% (p = 0.99 for CB and p = 0.12 for LVL), and hence on the incidence of SCE (p = 0.18 for CB and p = 0.81 for LVL).