“This is the time of year to begin proper management to reduce grass tetany incidence in your cattle operation,” says MU Extension Regional Livestock Field Specialist Patrick Davis.  Grass tetany is related to mineral imbalances in cattle and if not prevented can lead to sickness and death.  Therefore, Davis will discuss management strategies to reduce grass tetany incidence in your cattle operation.     

 “Spring lush forage growth leading to animal mineral imbalances results in grass tetany in cattle,” says Davis.  Spring forage has potential to be high in potassium and low in sodium which are important for absorption and utilization of magnesium by the animal.    Magnesium is the most often indicated mineral deficiency in grass tetany but recent evidence suggests deficiencies in sodium are implicated in grass tetany as well.  Therefore, Davis urges cattle producers to provide proper salt and magnesium supplementation free choice to reduce the incidence of grass tetany in cattle.

“Avoid grazing new grass till it reached 4 to 6 inches tall to reduce the incidence of grass tetany in your cattle herd,” says Davis.  Immature plants that are below this height have magnesium that is less available to the animal.  Therefore, Davis urges cattle producers to graze new grass at proper height for proper magnesium consumption to help reduce the incidence of grass tetany.  

“Planting legumes and maintaining adequate pasture fertility can help reduce the incidence of grass tetany in your cattle herd,” says Davis.  Legumes are high in magnesium compared to grasses, and through cattle consumption should help reduce the incidence of grass tetany.  Grass tetany is more likely in cattle grazing pastures over fertilized with nitrogen and potassium since these reduce the plants magnesium availability to the animal.  Davis urges cattle producers to test and properly apply nitrogen and potassium fertilizers to reduce the incidence of grass tetany.         

“Older early lactation cows are the most susceptible to grass tetany,” says Davis.  Early lactation cows are releasing large amount of magnesium in milk during lactation.  This combined with older cow’s reduced ability to mobilize bone magnesium leads to low serum magnesium levels and subsequent development of grass tetany.  Davis urges cattle producers to reduce the incidence of grass tetany by grazing less susceptible animals like dry cows, heifers, stocker cattle and cows nursing calves more than 4 months old on high risk lush green pastures.    

“Consult your veterinarian to plan treatment in case your cattle exhibit signs of grass tetany,” says Davis.  Grass tetany symptoms include unusual behavior, muscle tremors, frequent urination, staggers, and convulsions.  Davis urges cattle producers to visit with their veterinarian and plan treatment protocols in case cattle exhibit these symptoms because swift action may lead to saving the animal.     

“Cattle operation losses due to grass tetany can negatively impact productivity and profitably of the operation,” says Davis.  For more information on how to reduce the incidence of grass tetany in your cattle operation please contact your local MU Extension Livestock Field Specialist.