Reports indicate that grass supplies are very variable on sheep farms at present.
Some farmers who had a good grass surplus or who are lambing later and are building demand slower are still in a relatively good position, while others find themselves in a trickier position.
For the latter group, a significant increase in grass growth may get many out of trouble and back on track quickly. For others, careful management will be required to steer a course back on track.
While the change away from harsh northeasterly winds is providing kinder conditions, temperatures are forecast to remain relatively low. This means all farmers will need to keep a good eye on grass supplies over the coming week.
There are a number of management steps which can be taken to ensure animal performance is not compromised and grass supplies are given the best chance of recovering and building quickly once growth improves.
Supplement to conserve supplies
Where grass supplies are depleting fast, it is important to take steps to reduce demand and conserve remaining supplies.
This essentially leaves the option of introducing concentrate supplementation to fill the nutritional gap. Table 1 deals with the different scenarios which are present on farms.
If grass supplies are above 4cm, ewes will technically be able to consume enough grass to meet demand. However, where the aim is to slow down intake, introducing supplementation at a rate of 0.5kg per head per day will help where grass supplies still look OK for the next 10 days.
This will need to be increased to 0.8kg to 1kg where you have less than a handful of days grazing ahead.
Once ewes have reached peak milk yield, the merit of offering high levels of concentrates to them becomes increasingly questionable, especially if it is for a sustained period.
In such a scenario, there is a significant economic benefit in directing the concentrates to the lamb via creep feeding.
This, of course, will depend on aspects such as creep feeding equipment being available. Creep grazing should also be adopted where feasible.
A ewe’s grass intake potential jumps sharply from week four of lactation to week five of lactation, as detailed in Table 2.
At the same time, a lamb’s intake potential also increases significantly. This should be borne in mind when determining the likely grass demand in the coming weeks.
Check supplies regularly
Few sheep farmers are measuring grass on a weekly basis. Grass can still be managed, albeit not to the same precise level, by walking the farm regularly and assessing what supplies are present.
Forming grazing groups
There is a temptation when grass supplies are tight to leave ewes and lambs spread out over all the farm.
This may facilitate easier supplementation in smaller groups, but it has a significant downside, in that it will take significantly longer for grass supplies to recover and get ahead of demand again.
As such, you should continue to form your normal grazing groups as soon as possible. This will be essential when growth rates increase, as the situation can quickly turn from a deficit to a surplus at this time of year.
Wean early-born lambs
There is an added pinch point on some farms operating early and mid-season lambing flocks where the early lambing flock has depleted supplies apportioned to them.
Early weaning has cropped up in many discussions as an option to reduce grass demand from the ewe.
Grass intake of lambs increases rapidly from six weeks of age onwards, rising from 0.3kg DM/day in week six to 0.5kg DM/head in weeks seven and eight, followed by a further increase in intake to 0.7kg DM daily in weeks nine and 10.
Lambs can be successfully weaned early where they are consuming at least 250g/day concentrates on three consecutive days.
There is typically one of two options utilised – offer lambs the best grass available along with restricted concentrate supplementation; or transfer on to an intensive concentrate diet.
Reduce non-priority stock demand
Demand can be temporarily reduced by eliminating grass demand from non-priority stock, such as ewe hoggets. These can be temporarily housed on forage or supplemented outdoors in a well-fenced paddock until grass supplies recover.
Apply fertiliser regularly
Some farmers have held off applying fertiliser over the last week due to the inclement weather.
There is a far lower risk at this stage of the year of fertiliser being lost during a sustained period of low temperatures and negligible growth.
Therefore, continue to apply fertiliser as normal. Highly stocked farms are typically applying 25 to 30 units of nitrogen, with some applying higher where grass supplies are particularly under pressure and a low volume has been applied to date.
Lowly stocked farmers should still be applying in the region of 20 units to ensure supplies build sufficiently.
Applying a compound fertiliser over straight nitrogen will have benefits where there is a known soil deficiency or where swards are under pressure, with P and K helping recovery rates.