Do you sometimes wonder whether your stock have a trace element deficiency? And if they do, is it likely to be all of them or just some groups?
And is it likely to be all the time or is it associated with seasonal conditions? And which trace elements should I be concerned about on my farm?
Trace element deficiencies happen when there is an insufficient amount of the mineral in the food available for absorption by the animal through their gut to meet their needs.
Trace element deficiencies can also occur when there is an excess of other minerals that compete for absorption.
Young growing animals have the highest demand for trace minerals. For example, growing lambs need about twice the selenium in their diet that adult sheep require.
They are also born with minimal reserves stored in their body, so a dietary deficiency will become apparent sooner than in an older animal that has body stores.
The ingestion of soil is an important source of trace elements for an animal. Furthermore, lush, rapidly growing pasture is lower in trace minerals than slow growing or mature pasture.
The trace elements of greatest concern in Victoria are selenium, copper, cobalt and iodine.
The likelihood of a deficiency varies markedly across the state. It is worth researching which of those trace elements are most likely to be an issue on your property.
When you have established, by testing the soil and at-risk stock, any deficiency of trace elements on your property it is worth considering supplementing your livestock to prevent those diseases caused by the mineral deficiency.
This can be achieved using licks, drenches, rumen boluses and injections, with a particular emphasis on young, growing animals in seasons of plentiful pasture growth.
Care should be taken, however, if providing supplements in multiple forms as some minerals accumulate in the body and can cause toxicities.
For further information, contact your local veterinarian or Agriculture Victoria veterinary or animal health officer, or in NSW your Local Land Services, or visit the Agriculture Victoria website.
Dr Jeff Cave is Agriculture Victoria’s senior veterinary officer.