Parenteral micronutrient supplementation enhances mammary immune function and colostrum–milk quality by modulating cytokine profiles and oxidative stress in transition crossbred cows

Yallappa M Somagond^1,2Pravasini Das¹Ajay Kumar Dang¹Dhawal K Yadav¹Priyanka M Kittur¹Bibhudatta Samanta Kumar Panda¹Pooja Devi¹Aarti Kamboj¹Mohanned Naif Alhussien^3*

• ¹National Dairy Research Institute, Karnal, India
• ²ICAR - National Research Centre on Mithun, Medziphema, India
• ³Technical University of Munich, Munich, Germany

The present study assessed whether strategic pre- and peri-partum parenteral supplementation with trace minerals and vitamins could enhance mammary gland health and improve the immunonutritional quality of colostrum and milk in dairy cattle. Twenty-four multiparous cross-bred cows were blocked by parity and projected yield, then assigned to control, multivitamin (MV; vitamins A, B-complex, D₃, E), multi-mineral (MM; Copper (Cu), Manganese (Mn), Selenium (Se), and Zinc (Zn)), or combined multivitamin and multi-mineral (MMMV) groups; intramuscular injections were administered on days −30, −15, −7, 0, +7, +15, and +30 relative to calving. Longitudinal sampling on days 0, 2, 3, 4, 7, 15, and 30 postpartum revealed that MMMV cows produced colostrum and milk with higher fat and protein percentages, stable lactose, and greater concentrations of insulin-like growth factors and immunoglobulins than all other groups (P < 0.05). Mammary health indicators improved concomitantly: somatic cell counts fell, the neutrophil-to-macrophage ratio normalised, and phagocytic activity of both cell types increased. These functional improvements were accompanied by reduced expression of toll-like and chemokine receptors in milk phagocytes. Additionally, the cytokine profile shifted toward an anti-inflammatory state evidenced by lower levels of IL-1β, IL-6, IL-8, IL-17A, and IFN-γ, and higher levels of IL-4 and IL-10 as well as reduced oxidative stress, indicated by decreased activities of superoxide dismutase, catalase, and glutathione peroxidase in the milk whey of the MMMV group. The multi-mineral (MM) and multivitamin (MV) treatments conferred intermediate benefits, whereas the control group showed the greatest inflammatory and oxidative stress. Collectively, these findings demonstrate that repeated parenteral delivery of complementary trace minerals and vitamins throughout the transition period enhances mammary innate immunity, attenuates inflammation and oxidative stress, and augments the nutritive and immunological value of colostrum and milk, thereby offering a practical intervention to safeguard udder health and optimise passive immune transfer to calves.