Ewes in good condition during lactation produce more milk, which means larger lambs with higher survival and growth rates through to weaning. Feed on offer (FOO) during lactation is the driving factor.
Ewes in good condition will use fat reserves and pasture to provide high lactation levels, and will therefore tend to lose condition over lactation.
Daily milk production peaks at two to three weeks and 40–50% milk is produced in the first four weeks of lactation. Competition for feed between ewes and lambs begins about four to six weeks after lambing commenced. By 12-15 weeks of lactation milk production has almost completely ceased and the ewe is competing fully for feed with the lambs.
If supplementation is required then it is important to provide good levels of roughage in the diet, even low quality barley straw, as well as high quality grain.
Condition score target
(kg DM/ha green FOO)
Lambs eat pasture from around two weeks old and the lamb’s rumen is fully capable of digesting pasture by three weeks of age. However, lambs weaned before six weeks are likely to suffer as they can’t make up for the lost milk by suddenly increasing pasture intake. Lambs can increase pasture intake a little if milk intake declines but lambs under eight weeks are likely to grow better on their mother than if weaned.
Single lambs consume more milk and can grow around 80 grams (g)/day faster than twin lambs in early lactation and 35g/day faster than twins in late lactation. This occurs even if twin ewes are grazing high FOO pastures. Although ewes produce more milk for twins, these lambs get around 68% and 59% of the milk intake of single lambs in peak and late lactation respectively.
Imprint feed lambs
Imprint feeding of lambs with ewes before weaning will reduce the time required to train lambs to eat grain. At least four to six feedings of grain are recommended over a two to four week period so that lambs recognise the feeder and remember it.