Effect of subcutaneously released 24F-1,25-dihydroxyvitamin D3 on incidence of parturient paresis in dairy cows

J Dairy Sci. 1990 Feb;73(2):406-12. doi: 10.3168/jds.S0022-0302(90)78687-0.


Twenty-one aged Jersey cows were fed a high calcium diet prior to parturition to predispose them to parturient paresis. Eleven cows were implanted subcutaneously with pellets containing 24F-1,25-dihydroxyvitamin D3 7 d before the expected date of parturition and thereafter at 7-d intervals until parturition. Ten cows were left untreated to serve as controls. Incidence of parturient paresis among control animals was 80% (8/10). Treatment reduced the incidence of parturient paresis to 9% (1/11). The mean observed plasma calcium concentration nadir of implanted cows was 6.61 +/- .40 mg/dl, which was significantly greater than the plasma calcium nadir of 4.45 +/- .39 mg/dl observed in the control cows. Two steers were implanted with and three nonpregnant, nonlactating cows received intramuscular injections of 24F-1,25 dihydroxyvitamin D3 to contrast circulating plasma concentrations achieved by the two routes. Intramuscular injection and implantation resulted in plasma 24F-1,25 dihydroxyvitamin D3 concentrations above 300 pg/ml for the first 48 h after administration. From d 4 until d 11 after administration, plasma concentration was maintained between 164 and 89 pg/ml in the implanted steers. Plasma concentration was undetectable 7 d after an intramuscular injection. These data indicate that, with refinement, sustained release of 24F-1,25 dihydroxyvitamin D3 can be successfully used to reduce the incidence of parturient paresis.

MeSH terms

  • Animals
  • Calcitriol / administration & dosage
  • Calcitriol / analogs & derivatives*
  • Calcitriol / blood
  • Calcium / blood
  • Calcium, Dietary / administration & dosage
  • Cattle
  • Cattle Diseases / prevention & control*
  • Chi-Square Distribution
  • Drug Implants
  • Female
  • Male
  • Parturient Paresis / prevention & control*
  • Phosphorus / blood
  • Pregnancy
  • Random Allocation


  • Calcium, Dietary
  • Drug Implants
  • Phosphorus
  • 24-fluoro-1,25-dihydroxycholecalciferol
  • Calcitriol
  • Calcium