The 20 “sentinel chickens” based at Gooramadda, near Rutherglen, are tested each week for mosquito-borne viruses such as Ross River fever, Barmah Forest virus and potentially deadly Murray Valley encephalitis.

They are one of 10 flocks placed in towns along the Murray River, including Cobram and Wodonga, which serve as an early warning system about the threat of disease to humans.

District veterinary officer with the Department of Primary Industries, Jeff Cave, oversees the program at Wodonga and Gooramadda.

“The flocks have been strategically located so that they’re in a place where there are plenty of mosquitos and where they’re close to a population of people,” he said.

“They are just kind of one indicator that there might be something out there.”

Mr Cave said a fine needle was used to extract a small amount of blood which was sent away for testing.

The role of the sentinel chicken has never been so important.

Near-perfect breeding conditions over the past three months have seen massive increases in mosquito numbers across the Border and North East.

In the past three weeks, three cases of Ross River fever and one of Barmah Forest virus have been reported in the Hume region.