Prepartum measurement of serum biomarkers reflecting osteoclastic and osteoblastic bone metabolism for predicting the risk of milk fever in dairy cows

Abstract

We investigated whether prepartum levels of serum bone biomarkers are related to the degree of parturient hypocalcaemia and risk of milk fever (MF) in dairy cows with advancing parity. A total of 58 late-pregnant cattle were assigned to four groups: nulliparous, primiparous, multiparous in the 2nd lactation and multiparous in the 3rd–5th lactation. The multiparous cows were further assigned to MF and non-MF groups according to the onset of MF. Serum samples were obtained from the cows during the 3 weeks prepartum to 5 d postpartum period for the measurement of serum calcium (Ca) and three bone biomarkers: tartrate-resistant acid phosphatase isoform 5b (TRAP5b), osteoprotegerin (OPG) and bone isoenzyme of alkaline phosphatase (ALP3). The ratios of OPG to TRAP5b (O/T ratio) and ALP3 to TRAP5b (A/T ratio) were calculated. The data from all cattle showed that the severity of hypocalcaemia at parturition increased with advancing parity/age. The MF cows had elevated serum TRAP5b activity and a decreased O/T ratio after parturition, suggesting an increased number of osteoclasts due to osteoclastogenesis, in response to severe hypocalcaemia. The MF cows showed lower serum ALP3 activity during the 3 weeks prepartum than the non-MF cows, therefore, prepartum osteoblast function was likely weak in the MF cows. During the 2–3 weeks prepartum, serum ALP3 activity and the A/T ratio had moderate associations with the serum Ca concentration at day 0 (day of calving) in the multiparous cows, and receiver operating characteristic curve analysis revealed that ALP3 activity had excellent ability to predict MF. In conclusion, prepartum serum ALP3 activity is a promising biomarker to predict MF in multiparous cows.

Serum metabolic profiling in pregnant Holstein cows 3 weeks prior to parturition using two-dimensional gas chromatography time-of-flight mass spectrometry

“…Interestingly, ALP3 activity had a moderate positive association with serum calcium concentration on the day of parturition [19]. These findings suggest that osteoblast activity may be reduced in cows with MF during the prepartum period and that prepartum ALP3 activity has great potential as a predictive indicator for cows to develop MF.…”

“…To ensure effective preventive measures, it is crucial to identify predictive indicators of MF before parturition. Our recent study showed that the prepartum concentrations of serum bone biomarkers are related to the degree of hypocalcemia and risk of MF in dairy cows [ 19 ]. In particular, cows with MF exhibited lower serum activity of alkaline phosphatase isoenzyme 3 (ALP3), a specific biomarker for osteoblast function and bone mineralization, during the 3 weeks before parturition.…”

“…In particular, cows with MF exhibited lower serum activity of alkaline phosphatase isoenzyme 3 (ALP3), a specific biomarker for osteoblast function and bone mineralization, during the 3 weeks before parturition. Interestingly, ALP3 activity had a moderate positive association with serum calcium concentration on the day of parturition [ 19 ]. These findings suggest that osteoblast activity may be reduced in cows with MF during the prepartum period and that prepartum ALP3 activity has great potential as a predictive indicator for cows to develop MF.…”

“…We hypothesized that metabolomic analysis of cow’s serum samples will reveal useful biomarkers for predicting MF. In the present study, we performed two-dimensional gas chromatography mass spectrometry (GC×GC/MS)-based metabolomics analysis using prepartum serum samples from a previous study [ 19 ]. Considering the variation of ALP3 between MF and normal groups, we aim to identify serum indicators that can enhance our ability to predict the risk of MF in cows during the crucial 3-week prepartum period.…”

“…This study analyzed serum samples obtained from 25 late-pregnant Holstein cows approximately 3 weeks (18 to 23 days, average 20.7 days) before parturition ( Supplementary Table 1 ). These samples were originally collected for a previous study [ 19 ] and were kept at −80°C without a freeze–thaw cycle. The experimental procedures of animal care and blood sampling were complied with the Guide for the Care and Use of Agricultural Animals of Obihiro University of Agriculture and Veterinary Medicine (approval #19-49).…”