The United States has placed restrictions on Victorian poultry and poultry byproducts until further notice following an avian influenza outbreak.
More than 500,000 chickens from two farms in the state’s southwest have been culled after cases of H7N3 were detected at the properties.
The farms in Meredith and Terang are operated by Avgo and Surf Coast Eggs Farms and share management, staff and machinery.
On Saturday, the US Department of Agriculture imposed restrictions on avian products originating or transiting through Victoria backdated to May 22.
The restrictions apply to certain fresh poultry products, commercial birds, hatching eggs, byproducts and several other bird products.
Any imports to the US of processed products must now have a permit or government certification confirming they were treated in line with Department of Agriculture guidelines.
Pet or zoo birds, pigeons and doves can still be imported under a US government permit, but will be quarantined for 30 days in New York or Miami.
No restrictions have been placed on bird products from other Australian states.
The affected Victorian farms have been placed under quarantine conditions.
Victorian Farmers Federation president and egg farmer Danyel Cucinotta has previously estimated the outbreak and related cull could rob retailers of 450,000 eggs per day.
She predicted it could take between six months to three years for the impacted farms to return to normal production.
An Aldi spokesman told AAP customers may notice “small gaps on shelves in some stores” while Woolworths said it doesn’t expect the outbreak to impact its supply.