Feeding ewes to maximise lamb survival this spring

Jack Murphy, Teagasc Johnstown Castle, writes; on sheep farms the feeding management of the ewe pre lambing will have a massive bearing on mortality rates.

80% of foetal growth takes place in the last 6-8 weeks pre lambing.  This results in the ewe’s energy requirement being at its highest when her intake capacity is at its lowest.

Using your scanning results to separate ewes into singles, twins and triplets bearing should be carried out at a minimum. In addition to penning sheep by litter size you should also pen thin single bearing ewes with the twins and pen your thin twin bearing ewes with the triplet bearing ewes so that they get extra concentrate supplementation.

The above table is based of feeding 70 DMD silage to ewes in adequate body condition score. Depending on your own situation you may need to increase or reduce the level of concentrates fed. Feeding levels should be targeted to deliver lambs that are born large enough to maximise survival while at the same time minimising lambing difficulty associated with oversized lambs. The optimum lamb birth weights for lowland lambs are; Single 5.5-6kg, Twin 4.5 -5kg and Triplets 3.5 – 4kg.

Generally an 18-19% crude protein ration will be sufficient. For high litter size flocks a 20-21% protein nut may be required. High quality protein sources such as soya bean meal will increase colostrum/milk quality and production and good quality cereals such as barley, wheat and maize will maximise energy intakes. It is also essential that a suitable vitamin and mineral mixture is included as this will help prevent any deficiencies and reduce the risk of issues such as milk fever and grass tetany post lambing. 

The last month of pregnancy in sheep you will often see cases of vaginal prolapse on farm. If the number of vaginal prolapses exceeds 1% (one ewe in every 100) in your flock, you need to look at management factors which may be causing this. Ensure that forage is always set up in front of the ewes to avoid them overstretching when eating. If you are letting ewes out of a pen to feed concentrates avoid having them funnelling through too small of an opening. Once concentrate feed level exceeds 0.5 kg per head per day, split the feed into two equal feeds at least eight hours apart. Adequate trough space is vital to ensure that all ewes get access to their fair share of the concentrates and will help in reducing issues of prolapse. A general guide is that you can feed ten 70kg ewes or eight 90kg ewes in a standard 4.8m wide pen during late pregnancy.

National Hill Sheep Conference

This important conference is in Wicklow this year with a focus on flock health, breeding, biodiversity, and lessons from the recently completed SUAS EIP project. The conference is on Thursday 15 February at 7pm in the Glendalough Hotel, Eircode: A98 X9C1. The speakers on the night will include Dr. Philip Skuce of Moredun Research Institute, David Coen, from Sheep Ireland, Nicola Warden from CAFRE and Declan Byrne, Teagasc.

Finally, don't forget to complete the sheep census which can still be submitted online up until the 14^th of February.