Early turn-out pays
By James Garner
TURNING early lambing ewes and lambs out five to six weeks after birth leads to higher flock profitability than early weaning and intensive finishing, but the risk of failure is greater, according to Irish researchers.
Results comparing both systems at Knockbeg Sheep Unit, Carlow, Co Carlow, Ireland, suggest that profits may be higher when turning lambs out to pasture, but weather induced problems can cause lamb thrift to suffer, warns Teagasc sheep production officer and farms director Sean Flanagan.
"The grazing option is more profitable because it is much cheaper to finish lambs off grass. But a wet spring can cause problems and be difficult to manage.
"Early weaning and finishing lambs indoors offers more control over lamb feed intakes and allows a more accurate prediction of lamb performance. This is important because we want lambs to finish at 18kg carcass weight in 100 days; to achieve this, control is necessary," says Mr Flanagan.
Choosing to turn ewes and lambs out means weather or poor lamb thrift can hold up performance, leading to lambs missing the target and the market, he adds.
Irish sheep producers can still sell into an Easter market running through to mid-May, when main season lambs begin finishing. And unlike the UK, three quarters of lamb produced is exported. This means early season lamb, despite concerns over profitability, is still essential to Irish lamb production because it provides the continuity of supply required by its customers, says Mr Flanagan.
However, early lambing profitability concerns have raised questions about intensive systems requiring high inputs. "But it is possible to cut lamb intakes and costs by using a home-mix to replace compound creep."
This consists of 40 parts barley, 40 parts sugar beet pulp and 20 parts soya bean meal. Research at Knockbeg using this ration, costing IR£130/t (£112/t), found lamb finishing costs can be cut by IR£8 (£6.90) a head compared with a compound ration.
But researchers have also found that offering creep to lambs within a week of birth improves the success rate where ewes and lambs are turned out to grass after five weeks.
"Ample grass supply must also be on offer. When its not, there is no alternative but to early wean and finish lambs inside," says Mr Flanagan.
Ensuring grass is available for early lambers means nitrogen has to be applied in mid-February. After turn-out, management difficulties occur when its too wet to graze, meaning ewes and lambs have to be moved regularly to stop poaching and disease risks.
But one phenomenon from finishing lambs of grass remains a mystery. "Lambs finished off grass have heavier carcass weights – up to 1kg more – than indoor finished lambs, and theres no difference in fat levels when these lambs have been scanned."
Mr Flanagan says the explanation could be caused by environmental factors. "Lambs at grass exercise more and so have better muscle development. They eat grass, which may have an effect, and they may receive bypass protein from ewes milk," he adds.
• Grazing cheaper option.
• Need good grass growth.
• Extra carcass weight.