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Calcined Magnesite

Cal Mag is produced from the raw material Magnesium Oxide which is quarried around the world. Cal Mag offers the most commonly used and economic source of supplementary magnesium for ruminant livestock


Cal Mag provides a good source of dietary magnesium. The magnesium in Cal Mag is highly available during digestion. Due to its poor palatability, Cal Mag is normally included in TMR, Minerals, Mineral Buckets, compounds, blends or premixes.

Dairy cows
Small amounts are used in winter diets. The major use, however, is with Dairy Cows at turnout. Feed 50 – 60 grammes per head per day, commencing about 10 days prior to turn out, to help prevent Grass Staggers (Hypomagnesaemia). magnesium is not readily stored in the body so continue feeding during high-risk periods, eg: lush Spring grass
Dry Cows

Dry Cows generally have a higher magnesium level than Lactating Cows. This magnesium can be supplied by including Cal Mag in the diet or feeding Dry Cow minerals which have a high level of magnesium. It may sometimes be used in conjunction with magnesium chloride.

Suckler Cows & Beef
As with Dairy Cows, Cal Mag is primarily used at turn out.

Typical feed rates are 50 grammes/head/day.

Handling & Storage

Cal Mag should be stored in a cool, dry place. It may go lumpy / hard if stored for extended periods

Typical Analysis

Magnesium 50-52%

Pack Size

25kg or Tote bags