Abstract
The plasma concentrations of calcium, magnesium, inorganic phosphorus, and parathyroid hormone were measured in 15 parturient cows between a week before and after parturition. In 3 cows (affected with parturient hypocalcemia), the calcium concentration was at least 3.7, 3.9, and 5.8mg/dl within 24 hours after parturition. The inorganic phosphorus concentration also decreased with the decrease in calcium level. No changes were observed in magnesium concentration. Parathyroid hormone increased markedly in concentration in two of the cows after parturition. The parathyroid gland responded poorly to the decrement of plasma calcium level in the remaining cow on which no ordinary treatment was effective. Therefore, it was suggested that hypoparathyroidism might be detected from among paretic cows in the field.
