Uterine prolapse and hypocalcemia in dairy cows

Blood samples were collected from 53 dairy cows with uterine prolapse and from 53 cows with normal parturition (no uterine prolapse) matched by dairy as controls for various management programs among dairies. Cows with uterine prolapse had significantly lower total serum calcium content than did controls (P less than 0.01). Mean (+/- SEM) serum calcium content (mg/dl) for affected cows and controls were 6.08 (+/- 0.25) and 6.96 (+/- 0.20), respectively. Severe hypocalcemia (less than 4 mg/dl) was found in 10 (19%) of the affected cows, compared with 1 (1.8%) of the controls. Fifteen (28%) of the affected cows had moderate hypocalcemia (4.1 to 6.0 mg/dl), compared with 14 (26%) of the controls; 19 (36%) of the affected cows were mildly hypocalcemic (6.1 to 7.9 mg/dl), compared with 25 (47%) of the controls. Nine (17%) of the affected cows and 13 (25%) of the controls were within the normal range of calcium content (greater than 8 mg/dl). Nine of the affected cows were first-calf cows. The serum of these animals did not have significantly lower calcium concentrations, compared with controls matched by parity. Serum calcium values (mg/dl) for 9 first-calf cows and the 9 matched controls were 7.24 (+/- 0.42) and 7.00 (+/- 0.39), respectively. It was concluded that hypocalcemia was associated with uterine prolapse in multiparous dairy cows and, along with other factors, is involved as an etiologic factor for this puerperal condition.