Effects of vitamin D3 injection or drinking water administration on serum 25-hydroxycholecalciferol status of nursery pigs

Abstract Text:

Two experiments were conducted to evaluate the effect of administration of vitamin D₃ (VD₃) to nursery pigs by injection or by drinking water. At weaning, a total of 51 crossbred pigs (27 and 24 pigs in Exp. 1 and 2, respectively) were allotted to 3 replicates of 3 and 2 treatments for Exp. 1 and 2, respectively. Treatments were: in Exp. 1, 1) control, no vitamin administration, 2) intramuscular injection (INJ), 0.8 mL of 50,000 IU of VD₃ per mL at weaning, and 3) water administration (H2O), 5,493 IU of VD₃ per L of drinking water for 14 d postweaning, and in Exp. 2, 1) control, no vitamin administration, and 2) water administration (H2O), 92 IU of d-α-tocopherol and 5,493 IU of VD₃ per L of drinking water for 28 d postweaning. In Exp. 1, all pigs were injected with ovalbumin at weaning and d 14 postweaning as an immune stimulant, and in Exp. 2, the lightest 2 pigs within each pen were injected (INJ) additionally with 2 mL of 500 IU of d-α-tocopherol, 50,000 IU of retinyl palmitate, and 50,000 IU of VD₃ per mL. A common nursery diet was fed to all pigs during the experiments. In Exp. 1, serum 25-hydroxycholecalciferol (25-OHD₃) concentrations were increased after VD₃ administration (P < 0.01) in which the INJ and H2O groups had greater values than the control group through d 35 and d 21 post-administration, respectively [P < 0.05; peaks of 36.0, 46.0, and 79.1 ng/ml for control (d 14 post-administration), H2O (d 7-14 post-administration), and INJ (d 3 post-administration), respectively]. In Exp. 2, serum 25-OHD₃ concentrations were also increased after VD₃ administration (P < 0.05) in which those values increased to peak at d 3 post-administration in the INJ groups regardless of water treatment (P < 0.05; 146.6 and 154.4 ng/ml for control and H2O, respectively) and at 14 and 28 post-administration in the control and H2O groups without INJ, respectively (P < 0.05; 35.7 and 79.4 ng/ml, respectively). Even though the INJ groups had greater serum 25-OHD₃ concentrations than the groups without INJ through d 7 post-administration regardless of water treatments (P < 0.05), the H2O-only group had greater values than the INJ-only group from d 21 (P < 0.05; 76.4 and 64.5 ng/ml, respectively) post-administration onward. In conclusion, serum 25-OHD₃ concentrations in nursery pigs can be enhanced either by VD₃injection or drinking water administration at weaning.

Keywords: vitamin D₃, nursery pigs, injection, water administration