24,25-Dihydroxyvitamin D3 administration increases incidence of parturient paresis.
Fifty percent (7/14) of aged cows treated with 4 mg 24,25-dihydroxyvitamin D3 intramuscularly precalving developed parturient paresis shortly after calving compared with 7% (1/14) of controls. Injection of 24,25-dihydroxyvitamin D3 increased concentrations in blood plasma 15 times that in control cows. Blood plasma 1,25-dihydroxyvitamin D concentrations were elevated in all groups on day of calving but were not different. Injection of 24,25-dihydroxyvitamin D3 did not alter the typical plasma profile for calcium, phosphorus, or 1,25-dihydroxyvitamin D of paretic or nonparetic cows around parturition. Although injection of 24,25-dihydroxyvitamin D3 was associated with an increased incidence of parturient paresis, the mechanism remains unknown.
D015650:24,25-Dihydroxyvitamin D 3; D000818:Animals; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000453:epidemiology*; D004100:Dihydroxycholecalciferols / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D005260:Female; D007273:Injections, Intramuscular / Q000662:veterinary; D010319:Parturient Paresis / Q000097:blood / Q000453:epidemiology*; D011247:Pregnancy
D004100:Dihydroxycholecalciferols; D015650:24,25-Dihydroxyvitamin D 3; D002117:Calcitriol; D002118:Calcium