Use of cover by domestic
fowl
R.C. Newberry1 and D.M.
Shackleton2
1Agriculture & Agri-
food Canada, Agassiz, British; University of British Columbia, Vancouver,
Canada
Cover is structural feature
of the environment which animals may use to conceal themselves from predators
or aggressive conspecifics or to gain shelter from inclement weather.
Cover may also form a physical barrier limiting further progression.
To investigate factors influencing use of cover by domestic fowl, trials
were conducted with two strains of domestic fowl, each utilizing two rectangular
indoor pens containing approximately 110 chickens. Food, perches, a dust
bath and a brooder were located at each end of the pen, and water was provided
at the centre. The pen centre was divided into eight quadrants, four
with cover and four without cover. Cover was provided by a vertical
plastic sheet in the centre of the quadrant. The four plastic sheets
varied in visual continuity of cover: clear plastic, four vertical green
stripes painted on the clear plastic, eight such stripes, and solid green.
The location and orientation of cover structures (at right angles to the
air flow across the pen or at right angles to bird movement between the
resources at the ends of the pen and the water in the centre) was changed
weekly according to a Latin square design. Scan samples of quadrant
use were made weekly when the chickens were 3 to 7 weeks of age.
More chickens used quadrants with, than without, cover (P<0.01) and
a higher proportion rested and preened in quadrants with, than without,
cover (P<0.05). There was no increase in use of cover over the
four week period concurrent with the development of agonistic behaviour,
suggesting that use of cover was not motivated by attempts to avoid aggressive
conspecifics. The
orientation of cover did not influence use of cover (P>0.05) suggesting
that cover was not being used to gain shelter from cool draughts across
the pen or because the cover physically blocked the movement of birds between
the ends and centre of the pen. Use of cover was affected by the
degree of visual continuity of cover, with greatest use being made of quadrants
containing the cover structure with eight stripes followed by the structure
with four stripes (P<0.05), providing further evidence against shelter
seeking or physical barrier effects (e.g. bunching up behind a poorly visible
barrier) as the prime factors influencing use of cover. The results
support the hypothesis that, despite domestication and indoor housing,
use of cover by the chickens in this study occurred primarily as an anti-
predator response.