A new treatment to protect chickens against infection has been developed in Australia with the aim of phasing out the use of antibiotics in the poultry industry.

The system, developed by the country's national science authority CSIRO, provides a way of delivering antibiotic alternatives - natural proteins called cytokines - into chickens, substances that are naturally produced by poultry.

CSIRO researcher Dr John Lowenthal said: "Cytokines improve the immune response during infection and help combat disease. As such, they are excellent naturally-occurring therapeutics."

"When chickens were treated with cytokines their health improved and as a consequence they gained weight more quickly."

The researchers administered cytokines into chickens using harmless vaccine strains of viruses called adenoviruses, similar to vaccine strains commonly used in the poultry industry.

The original genes expressing cytokines were obtained from a single, live chicken. The genes were then able to be copied indefinitely for use thereby avoiding the use of further chickens," a researcher told just-food.com.