A note on fear reaction of three different genetic strains of laying hens to a simulated hawk attack in the hen run of a free-range system

摘要

Hens well adapted to free-range systems should react quickly to avoid an attack by a predator but should also be able to return to the hen run soon after to ensure good use of the outside area. To ascertain if some strains cope better with a frightening event the fear reaction of three different genetic strains to a simulated hawk attack in a free-range system was tested. Eight groups of 21 hens composed of the three different strains (LSL, ISA brown and ISA black), were exposed to a simulated hawk attack. Fear reaction and recovery times were video recorded and the use of the hen run was observed. Although the hens did react to the simulated hawk attack as expected by running back into or in direction to the poultry house, no significant strain differences were found either in the reaction or recovery time or in the course of the hen run used. Regarding fear reaction no strain was found to have better features for use as free-range laying hen regarding the behaviour after a frightening event.