The NSW Department of Primary Industries (DPI) has quarantined a second egg farm north of Young.
Initial tests at the State Government's Elizabeth Macarthur Agricultural Institute have confirmed H7 Avian Influenza (AI) on the property.
The DPI's first response team has the property under lockdown and planning is underway for eradication of the virus in line with nationally agreed protocols.
"This case follows the confirmation of H7 Avian Influenza in a flock of layer hens, also near Young, last week," NSW Chief Veterinary Officer Ian Roth said today.
"It is believed that the second case may be linked to the initial facility. Further tracing is underway to determine whether this is the case.
"The virus is definitely not the highly pathogenic H5N1 strain that has gained worldwide attention - nor is it closely related to that strain."
Mr Roth said the peak egg and poultry industry bodies have been advised and the property owners are co-operating with authorities.
"The depopulation of the first infected property near Young, confirmed last week, has been completed," he said.
The NSW Food Authority has confirmed that there are no food safety issues and that poultry and eggs remain safe to eat.
Visit http://www.dpi.nsw.gov.au for regular updates on the AI response.
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