Behaviour frequencies, spatial distribution and social network of Grimaud geese during the laying season.

Most domestic goose breeds were domesticated from the Greylag goose. Even though domestication resulted in a change in the production and behaviour of birds compared to their ancestors, geese are relatively recently domesticated and less intensively selected for production compared to other species (i.e. chickens or dairy cattle). In this respect, we hypothesised that the territorial defence of ganders would be present during the laying season similar to the wild ones. The behaviour of birds was expected to differ by sex, the month of the laying season and the time of the day. We assumed that the hierarchy within a group would be affected by the influence of other groups. Altogether 150 birds in three fifty-bird groups were examined over five observation events indicating the onset (December), the peak (the start, the middle and the end of January) and the end (the end of February) of the laying season. Twenty behaviour elements classified into five categories (locomotion, static behaviours, feed intake, comfort behaviours and social behaviours) were examined regarding the three groups as replicates. The territorial defence of ganders was evaluated by spatial distribution analysis, and the relations within groups were investigated by social network analysis. Between sexes, only the frequency of social behaviours presented differences. Ganders showed social behaviour more frequently than geese (10.89% vs 1.49%, P= 0.000). The frequency of static behaviours was the lowest at the onset of January and the highest in February (21.18% vs 38.03%, P= 0.000). The frequency of feed intake was the highest in December and the lowest in February (18.33% vs 4.83%, P= 0.000). Comfort behaviours showed the lowest frequency in December and the highest at the onset of January (36.65% vs 57.63%, P= 0.000). The social behaviours were unchanged in December and January but decreased in February (4.40–6.37% vs 1.16%, P=0.000). Only the frequency of social behaviours differed by the time of the day, indicating the highest frequency in the morning (55.60%, P=0.003). The results of the spatial distribution analysis did not strongly support the presence of territorial defence of ganders. The structure within a group was the most explicit in Group 1 having an adjacent large group and another small group by which it was likely to be influenced. It might be concluded that domestic geese ganders did not keep their territory-holding ability to a full extent during domestication and the behaviour (mainly social interactions) of domestic geese is influenced by sex, the month of the laying season and the time of the day. The structure within a group was somewhat influenced by the adjacent groups. • Geese ate more at the onset and ate less at the end of the laying season. • The frequency of social behaviours decreased by the end of the laying season. • Comfort behaviours showed the highest frequency at the peak of the laying season. • Compared to the wild ones, domestic ganders lost their territory-holding ability. • The hierarchy within a group can be strongly affected by the adjacent groups. [ABSTRACT FROM AUTHOR]