Most pastures in south-west Western Australia are comprised of annual species, growing in the Mediterranean climate cool wet winters, and senesced in the warm to hot dry summers. This inevitably means that there are periods in the year where pasture supply and livestock demand do not match:
- Autumn: There is little dry feed left after summer, and pastures germinate after the first rains in a cooling trend. This period is often termed the 'feed gap'. See supplementary feeding below.
- Winter: If pastures have established well in autumn, there is enough feed on offer, and the pasture growth rate keeps pace with livestock demand.
- Spring: Pastures grow rapidly in this period of adequate soil moisture and increasing day length and temperatures. Feed on offer and pasture growth rates are usually much higher than livestock demand. This 'excess' growth matures and provides a feed resource over summer.
- Summer: Pastures are dry, and are gradually trampled, eaten and lose their soluble components with any rain. Nutrition of pregnant ewes needs careful monitoring over this period, as feed supply is decreasing and feed demand is increasing.
Supplementing pasture feed in autumn is standard practice. Supplements include grains from cereals and pulses, hay, and manufactured pellets.
In drier than usual seasons, supplementary feeding may extend for long periods. A dry winter and spring means that supplementary feeding may be needed from early in summer through until pasture grows in winter. A dry autumn and winter means that the 'feed gap' may last for many months, and also result in less feed available over summer.
We recommend doing a feed budget for the full year: matching feed supplies with feed demand, and accounting for seasonal risk. Feed budgeting should be part of a livestock management plan, which can include things like livestock sales, agisting, and feedlotting. We also recommend doing a livestock water budget at the same time. Climate change, showing as reduced rainfall and higher temperatures in Western Australia, has resulted in greatly reduced runoff into farm dams, and a number of water deficiency (for livestock) declarations by government.
Sheep feeding and nutrition resources
These links provide information on pasture use, supplementary feeding, and other subjects related to good nutrition of sheep:
- Agisting livestock
- Alternative feed sources for sheep
- Annual feed budget for sheep enterprises: estimate the supplementary feed requirements of a sheep enterprise for a single year
- Annual pasture quality and quantity
- Breeding ewes are worth feeding
- Confined paddock feeding and feedlotting
- Drought feeding and management of sheep 2018: a PDF download (Agriculture Victoria)
- Feed cost calculator: calculate the lowest cost from a number of different sheep feeds
- Feeding and managing sheep in dry times: a PDF download
- Feed tests are vital for feed budgeting
- Grazing at the break of season
- Grazing winter and spring pastures
- Grazing stubbles and dry pasture
- Lifetimewool. Tools for managing your ewe flock (including feed budgeting)
- Pregnancy scanning
- Reproduction potential and marking rates of the WA sheep flock
- Pregnancy Scanning Benchmarks – Use this tool to view the latest pregnancy scanning rates (reproductive rate) of WA sheep flocks. Add in your own pregnancy results to see where you fit within the curve.
- Sheep feed value guide
- Sheep pregnancy scanning benchmarks
- Supplementary feeding and feed budgeting of sheep: this page provides a full explanation of the options and how to choose feed sources based on energy and cost. Jump to the introduction of feed grains section.
- Supplementary feeding calculator for pregnant and lactating ewes
- The good food guide for sheep: feeding sheep for meat production in the areas of Western Australia
- Tips for handfeeding sheep the right amount the right way
- Tools and calculators for sheep and grazing management
- Water quality for livestock