“Fear”, head shaking and production in five populations of caged chickens

1. Differences in “ fear”, head shaking and production traits were found among lines of chickens maintained in individual 0–46 × 0.30 × 0.46 m cages.

2. The differences among lines for “ fear “ and head shaking were consistent across three ages.

3. Although differences in “ fear “ and head shaking existed among lines for which there were large differences in production traits, the relationships within lines of production traits with modest “ fearfulness “ and head shaking were not important.