There was a grave clock, ticking somewhere up the staircase; and there was a songless bird in the same direction, pecking
at his cage, as if he were ticking too.
A strange idea was pecking
at his brain like a chicken in the egg, and very, very much absorbed him.
Perseveration in a guessing task by laying hens selected for high or low levels of feather pecking does not support classification of feather pecking as a stereotypy.
Feather pecking is a behavior by which birds damage or destroy the feathers of themselves (self-pecking) or other birds (allo feather pecking), in some cases even plucking out feathers and eating these.
And it ends with the brilliant lyric: "Woody Woodpecker pecking
on a tree/standing in the kitchen going peck, peck, peck, peck, peck, peck, peck, peck, peck .
Chronic pain was assessed by measuring pecking behaviour and beak sensitivity responses.
Beak trimming is performed early in the life of commercial hens to decrease injuries caused by cannibalism, bullying and feather and vent pecking (Savory, 1995).
Previously mated females again tended to select the loser of the males' pecking
competition, but virgins chose the winner.