مرتضی حسن آبادی - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran.
مهرداد مهری - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran &Center of Excellence in Ruminant Abortion and Neonatal Mortality, Ferdowsi University of Mashhad, Mashhad, Iran.
حسام الدین سیفی - Department of Clinical Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran & Center of Excellence in Ruminant Abortion and Neonatal Mortality, Ferdowsi University of Mashhad, Mashhad, Iran.

Recent studies suggest that vitamin D may have preventive and therapeutic effects on autoimmune disease, cancer, and diabetes type ۱ and ۲ beyond the skeletal condition and calcium metabolism. To demonstrate the effects of an over-supplemented single ۸ million I.U. vitamin D۳ IM injection on the modulation of immune responses and oxidative/antioxidative variables in transition dairy cows, this study was conducted on a commercial dairy farm with about ۱۵۰۰ lactating cows in the Tehran province, Iran. Twenty-four multiparous Holstein cows were randomly categorized into control and treatment groups. In the treatment group, ۱۲ cows received a single dose of ۸,۰۰۰,۰۰۰ IU vitamin D intramuscularly. In the control group, a placebo (distilled water) was injected into ۱۲ cows ۲ to ۸ days before the expected calving time. Blood samples were collected on ۲۱ and ۷ days before calving and ۱,۳,۷,۱۵, and ۳۰ days after calving. ۲۵(OH)vitamin D۳, tumor necrosis factor- α (TNF-α), interferon-γ (INF-γ), haptoglobin, interleukin ۶ (IL-۶), ferric reducing the ability of plasma (FRAP), glutathione peroxidase (GPx), superoxide dismutase (SOD), and hemolysate GPx were measured. This study showed that the treatment group had significantly higher amounts of ۲۵(OH) vitamin D۳, hemolysate GPx, and IL-۶ values than the control group. According to our results, vitamin D۳ injection increased the amounts of IL-۶ and hemolysate GPx activity and tended to affect serum GPx activity. 

Haptoglobin, immune regulation, Superoxide dismutase, ۲۵(OH) Vitamin D