During a recent webinar about grazing management on sheep farms, Philip Creighton of Teagasc spoke about the benefits of applying nitrogen (N) this spring.
Philip said: “Once we have built our grass covers as part of our closing plan, we need a number of things such as heat, moisture and N to boost growth rates.
“The decisions around what to apply and when to apply is based around our stocking rate (our demand) and how much grass we need.
“By applying N early we can see many benefits, especially in terms of reducing concentrate requirements and ultimately costs.
The average response to nitrogen (N) applied, is for every 1kg of N applied, we can grow up to 10kg of grass DM [dry matter].
“That, in terms of cost, if we take protect urea for example, at €400/t, that is going to cost us 87c/kg per kilogram of N applied.
“In terms of per kilogram of grass DM grown, that is going to cost us 8.7c.
“What’s the alternative? The alternative is that we don’t have grass or have very little of it and we are going to have to supplement the ewes with concentrates.
The less grass we have the more concentrates we are going to have to feed. So if we take concentrates at €330/t, that’s going to cost us 38c/kg DM.
“So the 10kg of grass we grew from the 1kg of N applied, would feed one ewe for four days in early lactation at a cost of 87c/kg.
“While to feed 10kg of concentrates would cost €3.80, which is about four times the cost of grazed grass.
“Now I know in reality we are not going to feed an all-concentrate diet but even if we had to supplement half the diet with concentrates post-lambing, that is going to be still twice as costly to feed the ewe compared to a mainly grass diet.
“So, getting as much grass in the diet as possible will go a long way in reducing concentrate feed costs. However, we need to make sure that if we are applying N that we do so when conditions are suitable.”