Consumers typically purchase fresh meat products based upon their appearance and an attractive, bright colour is very often a consideration for the purchase. However, some chickens are found to have yellowish-green colour in their meat. Is there anything wrong with these green chickens?

Unusual green colour in chicken meat is usually due to a condition known as Green Muscle Disease (or Oregon Disease) which is found in commercially raised broiler chickens. In poultry farming, broiler chickens are kept relatively inactive during the growing period. Consequently, the pectoral muscles (breast muscles) are not exercised enough to increase efficiency of its circulatory supply. As these muscles in poultry cannot expand in response to physical activity, a short period of sudden and excessive wing flap can compromise the blood supply and lead to degeneration and cell death in the tissue. The affected muscle has a characteristic swollen reddish-brown lesion that later becomes green and shrunken and then pale green, depending upon the time of induction of the vigorous wing exercise.

The lesion does not impair the general health of the chickens and is generally found during cut-up and deboning. The condition is not associated with any infectious or harmful substance and has no food safety concern other than affecting the aesthetic appearance of the meat.