Green Feed Supplementation - Grass Tetany Management
RumenWorks Nutrition

Grass Tetany Assist

  • Reduces the Risk of Grass Tetany
  • Supplements Low Magnesium Levels
  • Increases Available Energy

Green Feed Management

Grass Tetany, Phalaris or Ryegrass Stagers are the common names for the condition known as Hypomagnesaemia. This condition relates to inadequate levels of Magnesium in the cows system. Cattle are unable to store enough Magnesium in their bodies at certain periods of the year and as such require daily supplementation.

When Magnesium levels become critically low, normal physical function is compromised. Magnesium is a key element in the control of muscle actions; therefore, low Magnesium causes loss of appetite, muscle spasms or convulsions, muscle weakness or co-ordination issues-hence the term “staggers”.

When Magnesium levels get low the signals from the brain to muscle groups can get “scrambled” or not arrive. Green feed has a nutrient profile that interferes with the animal’s ability to absorb Magnesium. Rapidly growing feed has a high concentration of Potassium.

Potassium reduces the amount of Magnesium that can be absorbed, which can result in the low levels of Magnesium we are seeing with this metabolic disease. While in some cases, the visual signs of hypomagnesaemia are very prominent, we must consider what we cannot see. The onset of hypomagnesaemia is not sudden, there is a gradual development over time; we just cannot see it.

The true cost of hypomagnesaemia is not just the sick and dead animals, it is the animals that are effected internally but display very little external signs. As hypomagnesaemia effects muscle control, one of the first muscle groups affected is the digestive system, especially the rumen.

The decrease in rumen contraction rates and the strength of these contractions impact significantly on the performance of these animals. This decrease in rumen function results in a downward spiral in nutrient supply to the animal, therefore production, possibly resulting in more clinical signs of hypomagnesaemia or death.

The RumenWorks Range of Green Feed Licks simplifies the challenge of managing green feed and grass tetany easier. It does this by consistently supplying several forms of highly available Magnesium and energy to the animal, as they are dealing with the green feed challenge.

Grass Tetany Assist

Dose Rate:

Cattle and sheep consumption rates can vary due to individual conditions on property, and in the animal. As a guide to attain protection against Grass Tetany, the following dose rates should be used as a base point.

Dose Rate Cattle Sheep
200kg: 50g/day 30g/adult head/day
400kg: 100g/day
600kg: 150g/day


In high pressure situations such as Bloat and Grass Tetany the product must be continuously available. There must be adequate troughing. 1 trough to 25 head for cattle, 1 trough to 50 head for sheep. Spread the troughs around the paddock and near watering points.

Typical Green Feed Loose Lick Macro Nutrients:

Macro Nutrients g/kg
Calcium 130
Magnesium 99
Phosphorus 18.7
Sulphur 47.4
Sodium 82.68
Carbohydrates 174.2
Cattle Dose Rate: 100g/hd/day
Sheep Dose Rate: 30g/hd/day
RumenWorks Nutrition

Green Feed Supplement Products

To aid in growth rates, pasture utilisation, bloat and grass tetany management.

For product & soil type advice please get in touch.