Chicken

Chickens are long-domesticated birds that were raised by human farmers for food, and until relatively recently also used to entertain and encourage gambling in the form of cockfighting.

Background
In a world where chickens are apparently extinct, it seems some survived underground and lead short lives on the surface protected by the short-lived residents of the Hilltop Farm ruins. Miles was most likely the primary caretaker as the only one with farm experience.

Characteristics
Chickens are gregarious, domesticated fowl reared for meat and eggs. They are the most common and widespread domesticated animals whose ancestors were domesticated up to 8000 years ago for food and/or entertainment in the form of cockfighting.

Male chickens are known as roosters, while female chickens are known as hens. The hens lay eggs, which are fertilized by the rooster. Fertilized eggs, kept under the right temperature via the intervention of a hen or a climate-controlled environment, eventually reveal infant chickens, known as chicks.

Appearances
Actual chickens are referred to in Fallout 2, Fallout 3 as taste and Fallout Tactics in the form of graffiti. Others may be found but only as a means of calling someone afraid. Fallout 4's Far Harbor add-on and Fallout 76 are the only games that feature live chickens.