Mike the Headless Chicken

On September 10, 1945, farmer Lloyd Olsen of Fruita, Colorado, United States, had his mother-in-law around for supper and was sent out to the yard by his wife to bring back a chicken. Olsen chose a five-and-a-half-month-old cockerel named Mike. The axe missed the jugular vein, leaving one ear and most of the brain stem intact.
Despite Olsen's botched handiwork, Mike was still able to balance on a perch and walk clumsily; he even attempted to preen and crow, although he could do neither. After the bird did not die, a surprised Mr. Olsen decided to continue to care permanently for Mike, feeding him a mixture of milk and water via an eyedropper; he was also fed small grains of corn.

Link - Via How To Be A Retronaut