Hypocalcemia in Transition Dairy Cows: Immunometabolic Dysfunction,Diagnostic, and Preventive Management.

One of the most prevalent metabolic disorders affecting dairy cows during the periparturient period is hypocalcemia, which is increasingly viewed as a complex immunometabolic disease rather than a simple calcium deficiency. Recent evidence shows that complex interactions between endocrine regulation, immune dysfunction, oxidative stress, and metabolic adaptations play a role in the development of both clinical and subclinical hypocalcemia. Prevalence rates for clinical hypocalcemia range from approximately 3-10% and for subclinical forms up to 50% or more in multiparous dairy cows, thereby underlining its significant economic and health impact on modern dairy production systems. Impaired reproductive performance, reduced milk yield, increased susceptibility to mastitis, metritis, retained placenta, displaced abomasum, and decreased fertility have been associated with hypocalcemia. The review offers a comprehensive and up-to-date summary of the pathophysiological mechanisms driving hypocalcemia in dairy cows, focusing on immunological changes and oxidative stress pathways. Current knowledge on disruptions in calcium homeostasis is synthesised, along with advances in diagnostic strategies such as ionised calcium measurement and point-of-care testing, and recent developments in preventive and therapeutic approaches tailored to modern dairy farming. The review stresses the significance of early detection and tailored management approaches to enhance animal health, productivity, and reproductive performance.