[The suitability of 1-alpha-hydroxycholecalciferol for the prevention of recurrent parturient paresis in dairy cows].

Sixty-four cows with parturient paresis were given a standard treatment of 500 ml calcium gluconate (10.7 g Ca++) infusion solution. Twelve of these cows (experimental group = EG 1) additionally received 420 micrograms 1-alpha-hydroxycholecalciferol (1-alpha-OHD3) with 4 mg 25-hydroxycholecalciferol (25-OHD3) by the intramuscular route. A further 9 and 10 cows were given 210 micrograms 1-alpha-OHD3 and 2 mg 25-OHD3 (EG 3) with the calcium infusion, while 10 cows received either 420 micrograms 1-alpha-OHD3 (EG 4) or 210 micrograms 1-alpha-OHD3 (EG 5). Twenty-three cows (EG 2 and 4) which were given a calcium infusion alone acted as controls. The incidence of recurrence could not be reduced by the administration of Vitamin D3 metabolites concurrently with a calcium infusion, although calcium and phosphorus levels were higher between 24 and 48 hours after calcium infusion alone. The combination of 1-alpha-OHD3/25-OHD3 at the higher dosage resulted in the highest calcium levels.