Feed sources include maize, wheat (esp if there is a damp harvest in Australia), sorghum, other grains as well as soy meal. As producers here are dependent on imported feed, they are competing with other markets particularly China for feed to grow poultry.
A bumper dry harvest in Australia can result in the cost of feed rising as more of the wheat crop is destined for milling grade rather than going into the secondary feed market. Wet conditions at harvest can see more grain fail to make milling grade and end up as feed.
It can also foment instability elsewhere as it can cause the price of wheat to spike. Revolutions have been sparked by the rise of the cost of your daily loaf.