by David McCartney

What is magnesium?

Magnesium is a mineral which ruminants rely on for many body functions, including enzyme activation and energy metabolism.

How do ruminants store it?

70% of all magnesium is stored in the skeleton.

What happens if we don’t supplement?

If the animal doesn’t absorb the required level of magnesium, acute or chronic cases of hypomagnesaemia, also known as grass staggers, will be seen.

When animals are turned out onto lush pasture which is low in magnesium due to the way it grows, animals cannot mobilise their body stores quickly enough

and blood levels fall rapidly. This results in cases of acute grass staggers. If not found and treated quickly, acute grass staggers has a high death rate.

Chronic cases can also be seen, where blood levels of magnesium drop slowly over a longer period of time. Clinical cases are then brought on by a stressor, such as bad weather.

Which animals are at risk?

All ruminants are at risk of grass staggers, although acute cases are more often seen in older animals as the magnesium in the skeleton of older animals is not so readily available.

When and what should we supplement?

It is essential to supplement with bioavailable sources of magnesium all year round. Traditional sources of magnesium are very unpalatable and cannot be readily absorbed by the animal.

Triple mag is the combination of three sources of magnesium that is used across the Harbro range of cattle feed products. Triple mag is designed to be up to 50% more available than the traditional sources.

It is increasingly important to provide supplementation in the spring and autumn, when grass is lush and fast growing. Fast growing grass contains less magnesium than slow growing swards.

Which Harbro products are designed to reduce the risk of grass staggers in Suckler Cows?

• Triple Mag rolls, fed at 1kg/cow/day to provide their 30g magnesium requirement
• Super Suckler rolls, fed at 2kg/cow/day to provide their 30g magnesium requirement
• Super Suckler and Triple Mag mineral buckets to allow free access to supplementary magnesium
• Range of powdered minerals which can be incorporated into diets or be given free access

Our team of trusted advisors are on hand to recommend which products would work best on your farm.