Cathy Bunter, district veterinary officer, Ballarat
With the grain harvest wrapping up across the region, sheep producers are considering the benefits of grazing their flocks on stubble. The nutritional value of the stubble depends on the amount of residual grain and green plant growth from sprouted grain and summer weeds.
In drier years, the stems and leaves can be quite nutritious as less energy and protein has ended up in the grain. Windy weather can also cause grain to drop to the ground.
When making this decision, it's important to consider factors such as paddock size, stocking density, how much grain and green shoots remain and whether the sheep are maintaining their weight.
Stubble is low in calcium, but this can be corrected by providing licks, supplements or a simple limestone and 5% salt mix.
Adding trace elements, vitamins and urea, along with pellets or grains such as lupins to boost protein intake, will help address nutritional gaps.
When grazing sheep on stubble, it's important to keep an eye out for animal health issues, including:
- water belly
- grain poisoning
- polioencephalomalacia or thiamine deficiency
- nitrate and nitrite poisoning from oilseed crops like canola
- lupinosis from a fungus in lupins that produces a toxin.
Be careful not to overgraze the paddock and leave at least 50% ground cover to prevent wind erosion and help retain moisture in the paddock.
