Lactation tetany of mares (eclampsia, transit tetany)

Hypocalcaemia in mares causes lactation tetany, which is characterized by abnormal behaviour, in coordination and tetany. The condition also occurs in horses after prolonged physical exertion or transport. The disease was most common when the draft horse breeding was widely practiced.

Clinical signs include increased excitability in mild cases. Severely affected animals show profuse sweating, rapid laboured respiration dilatation of nostrils accompanied with synchronous diaphragmatic flutter, and signs of tetany such as stiff gait, muscle tremors, inability to chew, recumbency, convulsions and cardiac arrhythmias. In severe cases, the serum calcium is below 8 mg/dl. Untreated lactating mares may sometime die within 24-48 hours.

Slow intravenous administration of calcium borogluconate (300-500 ml of 25% calcium borogluconate solution) is effective in the treatment. Voiding of large volume of urine is one of the early signs of favourable response.