Veterinary Clinical Medicine-II

ETIOLOGY AND EPIDEMIOLOGY OF HYPOMAGNESEMIC TETANY

Etiology of hypomagnesemic tetany

• Short period of starvation (24-48 hrs) which may occur in association with transport also.
• High Po₄ intake competes with Mg absorption (cereals rich in K, lush green).
• No readily mobilizable large storage of Mg in the body.
• No efficient homeostatic mechanism.
• Loss of Mg in milk, urine & digestive secretions.
• Reasonably low level along with starvation may precipitate the disease.
• During inclement weather (cold, wet, windy weather), hyper activity of thyroid leads to inadequate calorie intake.
• Variation in susceptibility between individual animals .
• Cows turned out to lush pasture during spring after closed housing in winter.
• Grazing on young green cereal crops may cause wheat pasture poisoning.
• Dry cattle or beef cattle running at pasture in winter time, when nutrition is usually inadequate.

Epidemiology hypomagnesemic tetany

• Occur throughout the world. Commonly occurs in winter and in conditions where there is no proper shelter.
• Morbidity 2-12%.
• Case fatality is high (about 30%) – difficult to determine the cause as the affected animals are found dead.
• Can also occur in sheep, but less common.