Pregnancy-specific protein B (bPSPB) and progesterone monitoring of post-partum dairy cows with placental retention.

The relationship between placental retention, progesterone and pregnancy-specific protein B (bPSPB) was determined in 60 calving Holstein cows. The cows were divided into two groups with placental retention (WPR, n = 16) and no placental retention (NPR, n = 44). Every 4 days, until 60 days post-partum, blood samples were taken and the uteri were checked using ultrasonographv. The puerperal characteristics of NPR and WPR were as follows: mean days of abnormal vaginal discharge: 20.2+/-5 versus 35.6+/-7 (P < 0.01); mean intervals to uterine involution: 21.4+/-3.7 versus 27.6+/-7.6 days (P < 0.01); rate of endometritis: 25 versus 100% (P < 0.01). The mean numbers of oestrus cycles per cow were 1.75+/-0.5 versus 0.85-/+0.9 (P < 0.05) and the mean durations of the first oestrus cycle were 18+/-3.5 versus 16+/-2.1 days (P > 0.05). The mean intervals to first ovulation were 21.5+/-8.4 versus 35+/-19 days (P < 0.01). bPSPB blood concentrations were higher in the WPR group at calving with 955+/-170 versus 750+/-205 ng/ml (P < 0.01) and also during the first 32 days post-partum with 173.68+/-47.3 versus 131.0+/-29.2 ng/ml (P < 0.01). The mean bPSPB half-life was similar in the two groups: 6.9+/-2.5 versus 6.5+/-2.1 days (P > 0.05). In conclusion, it was found that placental retention was associated with a higher rate of endometritis, a lower number of cycles, longer interval to first post-partum ovulation and higher concentration of bPSPB at calving and during the post-partum period. The positive relationship between bPSPB concentrations and calf birth weight and their association with post-partum pathological events may be useful in monitoring animals presenting high concentrations at calving.