In its latest beef advice Teagasc highlights both spring- and autumn-calving cows going to grass suckling calves will be at risk from grass tetany.

It says it is particularly an issue if they are forced to clean out paddocks when weather is changeable, as it is too often in April. The other factor that will increase the risk is the increase in the use of potassium fertilisers as farmers try and rebuild low soil phosphorous (P) and potassium (K) indexes.

According to Teagasc the condition is due to an acute lack of magnesium (Mg) in the blood. Cows are unable to use stored Mg effectively and, for that reason, need a daily intake of between 20-30g of Mg.

Teagasc note there are a number of ways to supplement cows with Mg and it is a case of choosing the right one for your farm.