What is supplementary feeding?
Supplementary feeding is the additional supply of feed (usually grain, hay or silage) to sheep grazing a pasture or stubble which may be lacking in energy or protein. In Western Australia (WA) later in summer and autumn, supplementary feeding often becomes substitution feeding where sheep choose to eat the added feed rather than that available in the paddock.
Providing supplements allows the nutritional requirements of the sheep (which vary with age, frame size and pregnancy) to be met. It is especially important in preventing excessive liveweight loss during the dry pasture phase, particularly in weaners and pregnant ewes.
If you are growing sheep for meat production, seek professional advice regarding ration quality and the energy/protein ratios in the supplement.
Why supplementary feed?
Sheep are commonly supplementary fed during late summer, autumn and early winter to:
- improve utilisation of existing dry pasture
- meet the sheep's requirements by providing extra nutrients
- improve production to ensure that meat production or wool quality targets are met
- reduce the grazing pressure on establishing pastures to ensure that pasture growth rates are optimised in winter.
Improving utilisation of dry pasture
Supplementary feeding can improve utilisation of dry pasture or stubble by providing small amounts, 20-50 grams/head/day (g/h/d), of a supplement high in protein, for example lupins. However, this will only occur where the amount of dry pasture is non-limiting, at least of 1500 feed on offer (FOO), measured in kilograms of dry matter per hectare (kg DM/ha) and the quality is reasonable (50-55% digestibility). Providing high rates of feed (more than 100g/h/d) will lead to substitution where the sheep choose the supplementary feed over pasture causing reduced pasture utilisation.
Once the quality of the pasture falls to less than 50% digestible, energy becomes limiting for maintenance for all classes of sheep and feeding protein will not aid further utilisation of dry pasture. Feeds with high energy need to be fed to maintain sheep once digestibility and quantity has fallen below 50% and 1500 FOO (kg DM/ha) respectively.