For all breeding ewe systems, the success of the lamb growth window is hugely driven by milk yield of ewes. Whilst we do have some sheep dairy systems within the practice, attaching a cluster is not an easy option for the majority and we need some other way of assessing milk yield and ewe performance. Eight week weight is a useful proxy for assessing milk yield of your ewe flock. Hence why we recommend that at least some data is collected when lambs average 56 days old.
For the commercial ewe flock, the target for 8 weeks is 20kg. There will of course be a range so the second piece of information of interest is the percentage of light lambs (lambs <17kg) at this age. More than 10% of lambs classed as light lambs might indicate issues. Whilst there may be obvious reasons for some (ewe with mastitis, a lamb with joint ill) the lambs of first time mothers often feature here, and too many lambs at these weights may be a good indicator for next year that there are gains which can be made, and often simply!
We do have flocks within the practice with lots of EID equipment (and this of course does help), but recording 8 week weight (8WW) can be done with minimal equipment.
Top tips for recording 8WW
- If you haven’t recorded it before, start by just recording as few/many lambs as you can manage (and doing at the same time as clostridial vaccination can save a handling time). Pen, paper and analogue scales are all you need.
- Ideally record if lambs are singles or twins (it makes a big difference). Some farms even record by area/sward the lambs are on- all detail can help understand the results.
- Some EID kit on farm? Even if you just have a wand, put a tag in the lambs before you weigh, weigh the lamb and input in your wand- download the file and send to your vet. We have a TRUTEST wand and WEIGH HEAD which can be used in conjunction with your vet.
- Noticing very light lambs on the weighing? Clearly mismothered or a mum with mastitis or poor doer. There is lots of evidence that snatching at this stage and housing with access to good quality forage and creep can rescue performance and prevent long term stunting. Top tip – put them with your pet lambs – their enthusiasm for creep will draw in the newly weaned lamb.
- Remember to share your data with your vet. Large Flock Consultancy Members have data analysis included in their package and FHAP members can have some done as part of their visits too. We are now working with some flocks where we can compare year on year!
- Milk yield is heritable! As a closed flock – do you know who your milkiest ewes are? You do if you’re measuring 8 week weight!
Feel free to chat to Teamsheep about starting your data journey, or if you need to use our EID equipment!
Written By Emily Gasgoigne, Veterinary Surgoen
