Keyburn explained that stress in poultry is currently assessed through measuring the amount of hormone corticosterone in blood, which he said works because “corticosterone is released by the adrenalin glands when the bird’s body prepares for ‘flight’ or ‘fight’”.
Experts said levels of corticosterone are an important indicator of stress and form the basis for a valuable, non-invasive test. However, since the hormone is released in response to a variety of stresses, researchers said it does have its drawbacks and, despite a great deal of refinement and improvement, it is still difficult to pinpoint the precise cause of stress by measuring corticosterone levels. Tamsyn added: “Even the very act of taking a blood sample from a bird can dramatically affect corticosterone levels in less than a minute.”
Tamsyn and Keyburn plan to use miRNA profiling as a “definitive measure” of a bird’s welfare status, based on leads in other research findings. Crowley explained: “Recent studies investigating diseases in humans and other animals have shown clear differences in the expression patterns of miRNAs in the blood from healthy animals compared to those suffering disease.”
Poultry CRC CEO Mingan Choct said finding a non-invasive test for the health, production and welfare of farm animals is a topic of high priority. “The advent of genomics and molecular biology technology will help advance this important research area,” he added.
The project is led jointly by Dr Tamsyn Crowley and Dr Anthony Keyburn from Poultry CRC, both of whom will be using cutting-edge genetic technology to create a new welfare test, by drawing on the properties of “small non-coding ribonucleic acids (RNAs)”, also known as microRNAs or miRNAs.
