Assessment of endometrial cytology to diagnosesubclinical endometritis and its effects on fertility inrepeat breeder dairy cows

The objective of this study was to describe endometrial cytology to determine the prevalence of subclinicalendometritis (SCE) and iťs impacts on fertility in Repeat breeder dairy cows.Dairy cows parity 1 to 5 which were inseminated 3 or more times (the average number of AI in selected cows was3.8) were examined in 190±40 days in milk. Clinically normal cows (n=77) were selected based on the absenceof abnormal discharges on external inspection and also absence of abnormal fndings on transrectal palpation andultrasonographic examination.Endometrial samples were collected from the uterus using the lavage technique in the luteal phase of estrus cycle.Collected solution centrifuged and a drop of sediment was streaked on to a clean microscopic slide and stained withGiemsa. The percentage of polymorphonuclear cells(neutrophils) was counted for each specimen.Analyzed data showed that in the selected cows, the mean amount of neutrophils was 3/1 %(0-9) and the prevalenceof cytologically diagnosed SCE (based on more than 2% neutrophils) was 52/7 %(n=38).Cytologically diagnosed SCE was signifcantly associated with impaired reproductive performance.In this study, 25% of cows (n=18) became pregnant in the next service. Conception rate (in the next AI) was 5% forcows (n=38) with SCE (more than 2% neutrophils), and 47% for cows (n=34) without SCE(less than 3% neutrophils)(p=0.009).In conclusion, subclinical endometritis in repeat breeder cows which diagnosed by endometrial cytology wasassociated with reduced reproductive performance such as relative conception rate and increased risk of involuntaryor premature culling.