Grass staggers (also called hypomagnesaemia or tetany) is caused by magnesium deficiency.

It occurs when a cow’s intake of magnesium is exceeded by its output. Grass staggers is most commonly a disease of lactating cows at grass, because grass can be very low in magnesium but the magnesium output in milk is high.

Cows do not store magnesium and therefore rely on consuming it in their daily diet and from supplements.

The clinical signs of grass staggers can occur very quickly.  Like most nutritional diseases, the animals showing clinical signs are just the tip of the iceberg.  For every cow with obvious symptoms many more will be affected sub-clinically, which impacts their health.

The initial symptoms of magnesium deficiency are nervousness, ears pricked, nostrils flaring, eyes alert and head held high. Movement is stiff, like walking on stilts, and cows stagger when forced to move quickly. Cows suffer loss of appetite and reduced milk production. Death results from a “Tetany” where the muscles contract uncontrollably including the heart.

Treating grass staggers with magnesium supplements

Treating trough water with magnesium plays an important role in grass staggers prevention.

Your vet can help you determine the magnesium requirements specific to your farm soil and diet. Some farms with very high potash levels in pasture will require high rates of magnesium supplementation.

Where magnesium is added to water and dosage is not accurate there is a risk of the water becoming toxic and stock refusing to drink.

Therefore we recommend ‘small amounts frequently rather than large amounts sporadically’.  Using the PETA Multi-Purpose Dispenser treat animals on on a per animal/per day dosage using coarse agricultural salt or magnesium sulphate/chloride as carrier for smaller trace element mixes (powder or liquid).