Sheep feeding options in dry periods

Dec 2016

Feeding livestock during a dry period is no different to feeding livestock at any other time of the year. The basic principles and questions you need to ask yourself still apply – what feed do I have in the paddock, is it sufficient to meet livestock requirements (and production targets), and if not, what is the most cost-effective way to ‘plug’ the nutritional gaps? The following takes a look at supplementary feeding options in late summer/ autumn.

For late winter/ spring lambing flocks the months of January and February are all about ensuring ewes are in good physical condition and reach fat score targets in time for joining. Research conducted through the NSW Lifetime Wool project shows a clear relationship between fat score at joining and reproduction rates. The increase in reproduction efficiency is a result of more twin-bearing ewes.

The amount of supplementary feeding required during late summer is a function of the condition of the ewe, the quality of the pasture and to a lesser extent the quantity of pasture available.

Fat scoring to assess ewe condition enables you to fine-tune your feeding program. Ewes at fat score 3 will have minimal feed requirements as they can simply be maintained at this level. For information on how to fat score see the Department of Primary Industry (NSW DPI) Primefact 302 Fat Scoring Sheep and Lambs.

Ewes below fat score 2.5 have an increased risk of being dry. These ewes can be drafted off and allocated to better paddocks or supplementary fed to aid in joining.

As we move deeper into summer/autumn, pastures deteriorate in both quality and quantity (kilograms of dry matter per hectare, or kg DM/ha). Once digestibility of dry feed falls below 55% stock will start to lose weight, regardless of how much is in front of them. When dry feed becomes limiting energy requirements can then be met by feeding out cereal grains and/or hay.

However, dry standing feed is a valuable resource and should be utilised.

As shown in the table above, it only takes around 240g of barley per ewe per day to maintain liveweight when grazing dry standing pasture at 50% digestibility (assuming 1500 kg of DM/ha is present). Without the dry pasture the feeding rate would need to be increased to around 560 g per day! If you are unsure about the quality of your dry feed it is recommended that you send a pasture sample away for feed quality testing.

The quantity of supplementary feed will need to be increased if there is no feed left in the paddock. Table 2 presents some approximate feeding levels required to maintain liveweight in ewes using grain or hay (or the combination of both).

When ground cover becomes limiting, stock should be restricted to very small areas or stock management areas
(droughtlots) to minimise pasture damage and erosion.

Feeding stock in restricted areas also limits possible weed contamination from purchased fodder and maximises feed use efficiency by minimising travel distances to feed and water (i.e. stock are not walking off energy).

Sheep should be fed every day whilst being introduced to a new ration. After this initial introductory period, the ration can gradually be fed out less frequently (see guidelines below). If sheep are fed daily, each feed amount is small and dominant animals will eat more than their share at the expense of smaller, weaker animals. Research has shown that there will be a more uniform live weight across a mob, and fewer losses, if sheep are fed less often.

After the introduction program leading up to a survival or maintenance ration, sheep should be fed at these intervals:

• Dry sheep – twice weekly;
• Ewes in late pregnancy or lambing – every second day;
• Lactating ewes (after lambing has finished) – twice weekly;
• Early weaned lambs – feed ad lib until they reach 20 kg liveweight, and then feed every second day.

If possible, feed the roughage before the grain so that all sheep get some roughage. This also reduces the risk of hungry sheep overeating grain resulting in acidosis.

Notes on full hand feeding

• Cereal grain is commonly used to address energy deficiencies and is generally a cheaper source of energy than hay. Cereal grains (barley, triticale, wheat etc.) typically contain around 13 Megajoules of Metabolisable Energy (MJME) per kilogram of dry matter (M/D).
• The NSW DPI website has a feed cost calculator which can be used to compare different feeds to see which supplement gives you the cheapest source of energy.
• When full hand feeding cereal grains, it is important to add 1 - 1.5 % of finely ground agricultural limestone and 1 % salt. This helps prevent calcium deficiencies.
  Roughage should also be fed as it is necessary for healthy rumen function (especially in lactating ewes). Quality of the roughage is less important, so feeding low quality hay or stubble straw can be used.
• To reduce the risk of acidosis (grain poisoning) from feeding cereal grains, ensure an introductory period over 21 days is adhered to.

Take home messages

• The level of supplementary feeding is a function of ewe condition and pasture quality (digestibility)
• Fat scoring ewes and assessing pasture quality (and quantity) enables you to fine-tune your feeding program. This can significantly reduce your feeding bill while ensuring fat score targets are met for joining.
• Dry standing pasture is a valuable source of feed and should be utilised. When paddock feed becomes limiting, feed the cheapest supplement that will meet your livestock targets.