Male rank order, space use and female attachment in large flocks of laying hens

In a flock of 3500 modern laying hens with males present at an average ratio of 1:190 females and a density of 7 birds/m(2), male dominance, space use and eventual female attachment were studied by direct observations of the males and a total of 232 female focal birds. Territorial, sexual and agonistic behaviours were observed, as well as the location of the birds during daytime and night roosts. A rank order was determined based on crowings and matings and it was found that high-ranking males used more of the space available than low-ranking males (P < 0.05) and there was a positive correlation between male rank order and space use (r = 0.851, P < 0.01). However, most males used more than half of the area. The dominance hierarchy was maintained mainly by low-ranking males avoiding the higher-ranking ones. Furthermore, there appeared to be no strong female attachment to specific males. (C) 2004 Elsevier B.V. All rights reserved.