Sward height is key to lamb growth

Finishing lambs as quickly as possible from grass is one of the biggest challenges on a sheep farm. A key target for early to mid-March lambing flocks is to have 50% of lambs finished off grass by early September. Edward Egan, Teagasc Advisor Navan, has advice on achieving this
Why push to finish 50% of lambs by September?
Achieving this is particularly important for those flocks that run a high stocking rate. Having to high a proportion of your lambs left on your farm in September can have 3 major knock on affects.
- Lambs & ewes competing for grass when your are trying to build ewe body.
- More difficult to build Autumn covers.
- Later closing of paddocks in the winter means lack of spring grass.
This video below explains the key practices that you can put in place over the summer to maximise lamb growth from grass. If you want to maximise lamb growth rate then you must ensure your lambs are always getting the leafiest grass. The tendency on many sheep farms at this time of the year is to go into covers that are to high followed by grazing them down to low with lambs. The result is a reduction in lamb growth. This video details the correct pre & post grazing heights for a paddock system. It also outlines a number of options that you can put in place to ensure your lambs have the best quality grass after weaning. The basic idea is that you graze swards tight in April & May to reduce the proportion of stem in the sward during the remainder of the grazing season. However as we move through the summer the post-grazing heights for a rotational system & the sward height for a set stocked system must increase for lambs as shown in Table 1.
In a paddock system graze lambs down to 5.5cm in June. From July onwards the ideal post grazing sward height for lambs is 6cm.
Key practices include:
- Measuring grass weekly.
- Going into covers of 8cm with lambs.
- Grazing paddocks out in 3 days.
- Grazing to the correct grass height with lambs as shown in table 1.
- Follow lambs with ewes & or hogget’s to get good clean outs.
- Removing surplus grass quickly.
Watch this short video as Edward Egan talks about How to finish lambs off grass
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