Abstract
Plasma calcium and calcitonin levels were measured periodically during the two last
months of pregnancy and at the time of parturition in 9 pregnant mares and their foals.
In pregnant animals, there was an increase in plasma calcitonin levels in the days
before parturition, which was not due to any change in plasma calcium. This result
indicates that in the mare, as in the cow, in the days before parturition CT secretion
escapes from its control by plasma calcium.
In 0-day and 7-day-old foals plasma calcium levels were significantly higher than
in their mothers, but plasma calcitonin levels were not significantly different from
those observed in their dams at the time of parturition.
Key words
Calcium - Calcitonin - Horse - Newborn - Pregnancy - Parturition
