Association between conditions affecting the vaginal portion of the cervix or the cranial portion of the vagina and reproductive performance in lactating dairy cows.

were to characterize the prevalence of anatomical abnormalities and pathological conditions involving the vaginal portion of the cervix or the cranial portion of the vagina and evaluate its association with reproductive outcomes and removal form herd in lactating dairy cows. Primiparous (n = 1675) and multiparous (n = 3594) cows from 3 herds were enrolled in a prospective cohort study. The vaginal portion of the cervix and the cranial portion of the vagina were examined using a digital vaginoscope in cows ranging from 0 to 70 days in milk (DIM) or at insemination. Proportion cows with well-defined longitudinal cervical folds (≥75 % of surface) was affected by the interaction between DIM category and parity, as it was smaller for primiparous compared with multiparous cows evaluated 0 to 35 DIM, but not from 36 to 70 DIM. Proportion of cows with well-defined longitudinal cervical folds increased with greater postpartum intervals, but no further change was observed after 36 to 50 DIM. Cows with calving problems were less likely to have well-defined longitudinal cervical folds from 36 to 50 DIM. Cows diagnosed with adhesions (0.5 %), double external uterine ostium (1.7 %), vaginal septum (0.6 %), masses (1.2 %), urovagina (0.7 %), and scar tissue (0.9 %) represented a small proportion of the population, however only cows with urovagina had greater odds of becoming reproductive ineligible. Proportion of cows with metritis was 5.1 % (0-7 DIM) and 7.4 % (8-21 DIM), which was not associated with outcomes of interest. Proportion of cows diagnosed with purulent vaginal discharge (PVD) was 11.9 % (22-35 DIM), 8.5 % (36-50 DIM), and 6.3 % (51-70 DIM). Cows with PVD had reduced risk of receiving AI (51-70 DIM), smaller proportion of cows pregnant by 305 DIM (36-70 DIM), and increased odds of reproductive culling (36-70 DIM). The presence of bloody discharge at the day of AI was negatively associated with the odds of becoming pregnant.