Agreement among bacteriological findings, vaginal discharges, and endometrial cytology for endometritis detection in postpartum beef cows

Aim of the study: This study aims to demonstrate the relationship among vaginal secretions, bacterial isolates, and endometrial cytology during 20-30 days postpartum in beef cows. Background: Endometritis is one of the most common diseases that occurs in dairy cow after several weeks postpartum period. There is two types of endometritis, clinical and subclinical endometritis that cause severe economic losses by increased days open, calving interval and numbers of services to conception. Materials and Methods: A total of 82 beef cows, aged 3 years to 7 years and at 20-30 days post-calving, were enrolled in this study. All the cows were checked by transrectal palpation, ultrasound, and vaginal secretions collection. A four-grade system (0 = clear mucus, 1 = mucus containing flecks of pus, 2 = discharge including < 50% pus, and 3 = involving > 50% pus) was used to categorize vaginal secretions of these cows. Endometrial cytology and bacteriological samples were then collected using a cytobrush technique. Results: Nine of 82 beef cows (11%) had abnormal vaginal secretions (grade 1-3) and indicated to clinical endometritis (CE), and nine of 73 clinically healthy cows (12.32%) had subclinical endometritis (SCE, ≥ 8 % PMN cows). The agreement among endometrial examination, polymorphonuclear neutrophil percentage (PMN %), and vaginal discharge score (0-3) was moderate (k = 0.48, p < 0.01), whereas that between vaginal discharge score (0-3) and bacteriological finding was poor (k = 0.032, p = 0.51). The agreement between bacterial finding and PMN % was also poor (k = 0.15, p = 0.02). Escherichia coli was the most common bacteria isolated from healthy (14.6 %), CE (38.8 %), and SCE (42.8 %) cows. Moreover, E. coli was the major bacteriological risk factor for SCE occurrence. E. coli and Staphylococcus aureus were the most common risk factors for the occurrence of CE. Conclusion: A moderate agreement exists among PMN %, bacteriological findings, and vaginal secretions, whereas a poor agreement exists between bacterial findings and PMN %. E. coli, S. aureus, and dystocia were the major factors affecting uterine infection in beef cows. CE and SCE insignificantly affected the reproductive performance of beef cows.