Welfare and the structure of a battery cage: Size and cage floor preferences in domestic hens (1978)

Dawkins, M.

Abstract

Hens were found to prefer a larger [barren] over a smaller [barren] cage, and a cage with a grass floor over one with a wire floor. When cage size and floor type were opposed, hens chose to enter a small cage with a grass floor rather than a [barren] larger one with a wire floor. ... Size was a less important factor to hens than the presence of grass on the floor. .. The fact that cage size may not always be the most important factor to a hen is interesting in that it suggests that considerable improvements might be made to the housing of birds even where it may not be feasible to increase space allowance by very much.