Milk fever (hypocalcaemia) is a common metabolic disease at calving in dairy cows. Prevention through pre-calving management dramatically reduces incidence and associated welfare harm.
Milk fever causes profound welfare harm — affected cows are paralysed, unable to rise, and at risk of tympany, aspiration pneumonia, and death if treatment is delayed. Even sub-clinical hypocalcaemia causes reduced feed intake, impaired immunity, and increased susceptibility to other post-calving diseases including displaced abomasum and metritis. The transition period around calving is the highest disease risk period in a dairy cow's lactation cycle. Prevention-focused management — dietary adjustment pre-calving, calcium supplementation, and monitoring — significantly reduces incidence and represents a good return on welfare investment compared with treating established disease.