Sheep held in containment are beginning to, or soon will be, released to paddocks now pastures have emerged and are soaking up the sun and rains.
The change in feed from containment rations to paddock can be quite sudden and cause digestive issues, so care must be taken in making the transition. You can lose animals due to a sudden flush of protein and energy, so sheep should be vaccinated against enterotoxaemia prior to release. A 3-in-1 vaccine will suffice.
Provide good quality roughage to animals for at least 12 hours prior to release. Release sheep late in the day with full stomachs to reduce gorging on green pastures, and monitor the mob for the first couple of days. Shorter grazing times with gradual daily increases in the amount of time spent grazing in the new paddock may assist the transition.
Paddocks should have enough pasture to protect the soil and provide enough feed. To make a quick visual estimate of sown crop dry matter (DM), a good resource is the Livestock Feed on Offer Assessment Guide. The guide has photos of barley, oats, wheat, ryegrass, medic and vetch at different DM amounts.
The key is not to graze the crop too early. Wait until the plants root system is strong enough to prevent stock pulling it out of the ground, using the ‘twist and pull’ test to check. Usually this is about 6-8 weeks after sowing, when the crop is at 3-4 leaf stage and early tillering. The longer you can wait, the less need for supplementary feeding.
Pasture Dry Matter benchmarks:
- Dry sheep can be released into broadacre paddocks on a minimum of 500kg DM/ha if the daily pasture growth rates exceed mob requirements.
- Ewes in late pregnancy should not be released without supplementary feeding, until at least 1000kg DM/ha is available for grazing. The supplementary feeding will ensure they are getting enough nutrition, assist in diet transition and encourage further pasture growth.
- When DM is less than 1000 kg/ha, offer the full containment ration for 14 days during the transition period.
- It is not recommended to lamb in containment.
Another reason to supplement sheep that have been released from containment to the paddock, is that a sudden change in diet can also cause a break in the wool which reduces fleece value. Ewes in late pregnancy are more susceptible as this is when fibre diameter narrows.
On moving to new pastures, to reduce the risk of hypocalcaemia, provide a mixture of causmag:limestone:salt (2:2:1) at an allowance of 30 g/head/day. We know this is important on cereal based pastures, but with rising rates of hypocalcaemia the mix is being suggested for all pastures. This is very important for older ewes and ewes carrying multiples that are at higher risk. Intake of loose licks can be variable between animals, so where possible, mix with the ration or supplement for better intake. Try to keep the mixture weatherproof to keep it palatable and encourage intake. Provision of roughage can also assist in mineral metabolism. Stress can induce hypocalcaemia, so keep stress events and time off feed to a minimum for pregnant ewes and avoid yarding during the last 4 weeks of pregnancy.
For more information:
National procedures and guidelines for intensive sheep and lamb feeding systems
