Influence of different therapy approaches: With or without manual extraction of retained placenta on reproductive performance in Simmental cows

The aim of the research was to determine the influence of different methods used in the therapy of retained placenta on conception rate and duration of days open in cows. Research was performed on 241 Simmental cows aged 2-8 years divided in three groups. The first group of cows (group A) (n=82) with retained placenta was treated with manual extraction of placenta 12-24 h after parturition combined with application of intrauterine antibiotics. The second group (group B) (n=79) with retained placenta was treated with intrauterine antibiotics only 12-24 h after parturition and repeated 2-3 times in 48 h intervals. The third group (group C) (n=80) was the control group and had physiological puerperium (without retained placenta). To assess the reproductive performance of Simmental cows, interval from calving to first insemination (days open to first service, DOFS), interval from calving to pregnancy (days open to pregnancy, DOP), relative pregnancy rate (%), first service conception rate (FSCR, %) and all service conception rate (ASCR, %) were measured. The estimate of hazard ratio for DOFS in group A relative to cows in group B was 2.20 (p is less than 0.0001), implying that cows in group B had oestrus earlier and were open shorter until the first insemination, that is, the relative rate of first service decreased by 54.5% in the group A while holding all other variables constant. The variable that had a significant influence on DOFS was lactation (HR=0.99; p is less than 0.0001). The estimate of hazard ratio for DOP in group A relative to cows in group B and C was 3.53 (p is less than 0.0001) and 1.73 (p is less than 0.0001), respectively, implying that cows in group B and C were open longer until pregnancy, that is, the relative rate of pregnancy in group A decreased by 71.6% and 42.2% in comparison with group B and C while holding all other variables constant. Variables that had a significant influence on DOP were lactation (HR=0.99; p is less than 0.0001) and peripartal diseases (HR=0.48; p=0.02). The estimate of hazard ratio for DOFS and DOP between group B and C was not significant. Cows treated with intrauterine foaming tablets after RFM became pregnant earlier and had a better conception rate in contrast to cows treated with manual extraction of placentae.