Association between subclinical hypocalcemia and postpartum health disorders in dairy cattle

Abstract

In dairy cattle, parturition and the onset of lactation lowers blood calcium concentrations (hypocalcemia) that can result in a clinical (milk fever) or subclinical condition. Cows with milk fever have paresis and require prompt calcium treatment. In contrast, in the sub-clinical form of hypocalcemia (SCH) the lower blood calcium concentration does result in paresis but does affect smooth muscle function (Huber et al., 1981) and immune function affecting health (Risco et al., 1984, 1994; Martinez- Patino et al., 2012). Many dairy producers have adopted the practice of feeding acidogenic diets prepartum that has contributed to a notable reduction in the incidence of milk fever with an average reported of 2.4 % (Reinhardt et al., 2011). However, despite the application of these diets, the prevalence of subclinical hypocalcemia (SCH) remains at 25 and 47% in primiparous and multiparous cows, respectively. Because of the higher prevalence and impact on health, there has been a resurgence in the interest to develop SCH prevention and therapeutic strategies. This paper discusses the association between hypocalcemia, postpartum health disorders and risk for metritis related to a reduction in immune function in dairy cattle. In addition, therapeutic considerations for SCH are discussed.