Grass Tetany is typically seen in which animals?

• A. Lactating cows and older cattle
• B. Growing calves
• C. Horses
• D. Sheep

Answer: (A)

Grass tetany is a magnesium deficiency that occurs when ruminants graze on lush, rapidly growing pasture. It is most commonly seen in lactating cows and older cattle because milk production raises magnesium needs and aging can reduce mineral absorption and rumen efficiency. When forage is high in potassium and relatively low in magnesium, the animal’s body can’t keep enough Mg in circulation, leading to the neurological signs of tetany. Growing calves, sheep, and horses can be affected under certain conditions, but the classic risk group is lactating dairy cows and older cattle.