ABSTRACT:
This study aimed to evaluate the effects of type of calving (eutocic vs. dystocic), season of the year (rainy vs. dry) on retained placenta (RP) and subclinical endometritis (SE) prevalence, to verify the relation between these diseases, as well as its effects on culling rate, days open and number of AI/conception. Retention of fetal membranes was recorded on first day postpartum. Endometrial cytology was performed between 30 and 80 days in milk (DIM) and positive cases were considered ≥5% neutrophils. Data were analysed by logistic regression and analysis of variance on Minitab program (P<0.05). The prevalence of RP was 14.93% (69/462) and of SE was 27.49% (127/462). A tendency of effect of RP on SE prevalence was detected (P=0.10). Dystocia increased RP prevalence (P<0.05). Cows that calved during rainy months had greater SE prevalence (P<0.05). RP increased culling rate (P<0.05), calving to conception interval (P<0.05) and number of AI/conception (P<0.05), although SE occurrence did not affect these variables (P>0.05). In conclusion, RP tended to be a risk factor for SE, dystocia is a predisposing factor for RP and calvings that happens during rainy period increases SE. There is a negative impact on reproductive efficiency of crossbred dairy cows that had retained placenta.
INDEX TERMS:
Placenta; endometritis; reproduction; dairy cows; Bovine; postpartum