Author: Carley Lewis, Biosecurity Coordinator, Animal Health Australia

As we head into what the Bureau of Meteorology (The Bureau) is predicting will be a hot and dry spring and summer for much of Australia, livestock producers will be considering and planning for the practical implications this will have for their animals and their business. The confirmed El Niño will likely lead to reduced rainfall in the east for spring and early summer, and a positive Indian Ocean Dipole (IOD) is expected to cause reduced spring rainfall in central and south-east Australia. The Bureau is expecting the drying effects of this concurrent El Niño and positive IOD event to persist until at least the end of February 2024. While this weather outlook will have many implications for agricultural production, this article will consider the potential biosecurity risks that may arise in relation to water and feed sources for livestock.

During periods of reduced rainfall and persistent heat, natural water sources may quickly become depleted and both wild and feral animals (e.g., feral goats and pigs) will compete with livestock for water if they can gain access to it. This poses a significant risk of disease transmission, particularly in extensive and free-range operations where wild and feral animals are most likely to gain access to dams, troughs, surface water and water tanks that are not bird-proof. Some examples of diseases that can be transmitted in water include botulism and salmonellosis, as well as some emergency animal diseases such as foot and mouth disease (FMD) and highly pathogenic Avian Influenza (HPIA).

Some solutions to maintaining safe and clean water supplies include the following:

  • Checking and maintaining boundary fencing around paddocks to keep wandering animals away from your livestock and water sources. This also applies to fencing around catchment dams, which will also protect them from damage and serves as a safety measure.
  • Wild waterfowl can be deterred from accessing water by safety measures such as exclusion netting and audio/visual deterrent techniques.
  • Develop and implement an effective water sampling protocol to assess the level of organic material in your water supply, providing treatment if necessary.
  • Prevent the accumulation of run-off water around sheds and production areas as this may also attract wild birds and pests such as rodents.

When rainfall decreases, the pasture supply and quality is impacted. Producers may need to buy in feed from other regions or states to meet the nutritional and energy requirements of their livestock. This, like with most farm inputs, increases the risk of pests, weeds and diseases being brought into the area and onto farms. It is also important to note that states may have biosecurity requirements for the importation of livestock fodder and feed. For example, Victoria requires sampling of hay for the presence of annual ryegrass seeds.

With regards to buying in feed, producers should:

  • Comply with all state biosecurity requirements relating to the importation of feed and fodder.
  • Always ask for a Commodity Vendor Declaration and ensure any feed containing restricted animal material (RAM) is never supplied to ruminants.
  • Conduct a visual inspection of fodder and feed for any signs of weed seeds or pests (e.g., rodent droppings), and keep an eye out for any weeds that may pop up in paddocks following the placement of feed or fodder.