Blood urea nitrogen may serve as a predictive indicator of retained placenta in dairy cows.

Retained placentae (RP) results in significant economic losses to dairy farmers. In Experiment 1, to screen biochemical indicators of RP, 21 cows with RP and 21 cows with no retained placenta (NRP) were selected as a control group, and blood was collected at -7 d, 0 h (parturition) and 12 h. Serum biochemical indicators were ascertained. Results indicate serum concentrations of phosphorus (P) and blood urea nitrogen (BUN) in cows of the RP group were markedly greater than in cows of the NRP group at -7 d (P < 0.01). In Experiment 2, to evaluate predictive indicators for RP, 34 cows with RP and 34 cows with NRP were selected, and there was blood sampling at -15 d, -10 d, -7 d, -4 d, and -1 d. Serum P, BUN, and total protein (TP) were evaluated. Associations of values among the three indicators and occurrence of RP were analyzed using binary logistic regression. Results indicate there was a negative correlation between only the values for BUN and RP (P = 0.016). In Experiment 3, to test hypothesis that relatively greater concentrations of BUN effects immune function in placental tissues, four cows were selected, placentae were collected at 0 and 12 h, and hematoxylin-eosin (HE) staining was performed. Results indicated that the extent of inflammatory cell infiltration and vascular proliferation were less at the 12 than 0-hour timepoint. Taken together, BUN at -7 d may serve as a predictive indicator of RP in cows.

Validation of a 13,14-dihydro-15-keto-PGF(2alpha) enzymeimmunoassay and its application for reproductive health monitoring in postpartum buffaloes.

The objective of the present study was to validate a simple, sensitive and direct enzymeimmunoassay (EIA) procedure for 13,14-dihydro-15-keto-PGF(2alpha) (PGFM) for use in buffaloes with postpartum reproductive disorders and determine the practicalities of using plasma concentrations of 13,14-dihydro-15-keto-PGF(2alpha) for monitoring their reproductive health. The EIA was used for determination of the circulating levels of PGFM associated with the retention of fetal membranes, postpartum endometritis and variable postpartum intervals. The concentrations of PGFM with retention of fetal membranes in the periparturient period were lower as compared to buffaloes that had uneventful parturitions. Concentrations of PGFM associated with postpartum endometritis were elevated as compared to those in buffaloes free of reproductive tract infections. Buffaloes having higher plasma concentrations of PGFM in early postpartum period had shorter postpartum intervals, indicating the association between PGFM concentrations postpartum and uterine involution as well as the resumption of estrous cycle in this species. The study presents the possibility of using circulating PGFM concentrations for monitoring the postpartum reproductive health of buffaloes.