TY - JOUR
T1 - Effects of obstructed take-off and landing perches on the flight accuracy of laying hens
AU - Moinard, C.
AU - Rutherford, K. M D
AU - Haskell, M. J.
AU - McCorquodale, C.
AU - Jones, R. B.
AU - Green, P. R.
PY - 2005/9
Y1 - 2005/9
N2 - Laying hens housed in extensive systems may be at risk of injury when many birds compete for use of the same perch space. Experiments were carried out to determine the space required by laying hens to move between obstructed perches. Eighty Lohmann Brown layer hens were reared in floor pens fitted with perches from 1 day of age. After the peak of lay (25 weeks of age), their ability to jump to and from perches obstructed either by inanimate objects or by live hens was assessed in four experiments. Digital video techniques were used to make detailed measurements of take-off, flight and landing behaviours. In Experiment 1, birds jumped upward or downward at a 14°angle between two perches that were separated by a horizontal gap of 80 cm. Two inanimate obstructions were placed on either the take-off or the landing perch, with a space between them of 15 cm (the minimum perch space required under European directive 1999/74/EC), 22.5 or 30 cm. Experiment 2 was similar but included a condition in which obstructions were placed on both the take-off and landing perches. Experiment 3 compared the effect of obstructing the landing perch with hens or with inanimate objects. Experiment 4 tested the effect of placing a single hen on the landing perch, directly in front of the test bird, on its detour behaviour. With a 15 cm space between obstructions, hens made significantly more successful jumps when the obstructions were on the take-off perch than when on the landing perch (P < 0.05). In the first case, birds delayed their first wing beat when taking off (P < 0.01), while in the second they spent a longer time airborne (P < 0.05), made more wing beats (P < 0.05) and took longer to achieve balance on landing (P < 0.05). The presence of obstructions on both perches did not have any cumulative effect on behaviour, and there was no evidence that obstruction by other hens had effects different from those of inanimate obstructions. When it was possible, hens preferred to walk along the take-off perch so as to avoid a diagonal path when jumping to avoid another hen directly in front of it (P < 0.001). The results indicate that, while laying hens are often able to jump from or into a 15 cm space between obstructions, this requires changes in take-off and landing behaviour which incur costs in terms of energy expenditure and the risk of collision. © 2004 Elsevier B.V. All rights reserved.
AB - Laying hens housed in extensive systems may be at risk of injury when many birds compete for use of the same perch space. Experiments were carried out to determine the space required by laying hens to move between obstructed perches. Eighty Lohmann Brown layer hens were reared in floor pens fitted with perches from 1 day of age. After the peak of lay (25 weeks of age), their ability to jump to and from perches obstructed either by inanimate objects or by live hens was assessed in four experiments. Digital video techniques were used to make detailed measurements of take-off, flight and landing behaviours. In Experiment 1, birds jumped upward or downward at a 14°angle between two perches that were separated by a horizontal gap of 80 cm. Two inanimate obstructions were placed on either the take-off or the landing perch, with a space between them of 15 cm (the minimum perch space required under European directive 1999/74/EC), 22.5 or 30 cm. Experiment 2 was similar but included a condition in which obstructions were placed on both the take-off and landing perches. Experiment 3 compared the effect of obstructing the landing perch with hens or with inanimate objects. Experiment 4 tested the effect of placing a single hen on the landing perch, directly in front of the test bird, on its detour behaviour. With a 15 cm space between obstructions, hens made significantly more successful jumps when the obstructions were on the take-off perch than when on the landing perch (P < 0.05). In the first case, birds delayed their first wing beat when taking off (P < 0.01), while in the second they spent a longer time airborne (P < 0.05), made more wing beats (P < 0.05) and took longer to achieve balance on landing (P < 0.05). The presence of obstructions on both perches did not have any cumulative effect on behaviour, and there was no evidence that obstruction by other hens had effects different from those of inanimate obstructions. When it was possible, hens preferred to walk along the take-off perch so as to avoid a diagonal path when jumping to avoid another hen directly in front of it (P < 0.001). The results indicate that, while laying hens are often able to jump from or into a 15 cm space between obstructions, this requires changes in take-off and landing behaviour which incur costs in terms of energy expenditure and the risk of collision. © 2004 Elsevier B.V. All rights reserved.
KW - Hens
KW - Jumping
KW - Obstruction
KW - Perch
UR - https://www.scopus.com/pages/publications/23744504427
U2 - 10.1016/j.applanim.2004.11.016
DO - 10.1016/j.applanim.2004.11.016
M3 - Article
VL - 93
SP - 81
EP - 95
JO - Applied Animal Behaviour Science
JF - Applied Animal Behaviour Science
IS - 1-2
ER -