For decades, Australia's countryside was ravaged by billions of rabbits. So in the 1950s, the government released the disease myxomatosis to kill off the rabbit plague. We hear from farmer, Bill McDonald, who remembers Australia's battle against the bunnies. (This programme is a re-broadcast).(Photo: Rabbits around a waterhole at the myxomatosis trial enclosure on Wardang Island in 1938. Credit: National Archives of Australia)