By Poppy Frater, SAC Consulting, sheep and grassland specialist

At the recent ‘Maximising Live Lambs’ conference, hosted by SAC Consulting at Roslin Institute, the two farmer speakers, Graham Lofthouse and Donald Barrie, mentioned weaning date as a tool to help the ewe regain condition, manage gimmers and improve lamb growth.

When we consider the biology of milk supply, peak milk production occurs at three to four weeks post-lambing. At this stage, milk can fully meet the lamb’s dietary requirement.

However, from four weeks, milk supply declines. As such, at six weeks, half a twin lamb’s diet will be milk and the other half will be grass or other feeds. As milk supply drops, the lambs depend more on other feeds, mainly grass, in order to fulfil their demands, this puts them in competition with their mothers.

If quality grass is in good supply, competition is not a problem. However, if the lamb weights are dropping below 150g/day and/or ewes are lean, consider weaning after the lambs are eight weeks old to target the ewe and lamb nutrition independently.

Lambs can be given the best quality fields on the farm – high clover pasture, silage aftermaths or specialist crops such as plantain, red clover or hybrid brassicas. Thin ewes and gimmers are the next priority and the fat ewes can be put to the poorer pasture to alleviate pressure on pasture supply. Target minimum lamb weaning weight is 25kg, unless the lambs are being moved to high protein crops, such as red clover.

Mr Lofthouse found it beneficial to wean his lambed hoggs at 10 weeks, this gives them more opportunity to grow well before the next mating where the target weight is 52kg. Mr Barrie now weans at 12-13 weeks which has helped him get the ewes to target condition by mating time – a key influencer of the size of next year’s lamb crop.

The Live Lambs project was funded through the Knowledge Transfer and Innovation Fund from Scottish Government. Please see the following webpage,, for various resources developed through the project and the presentations from the Maximising Live Lambs event.