Evaluation of ground reaction forces produced by chickens walking on a force plate.
OBJECTIVE
To evaluate the use of a force plate as a method for objective gait analysis in adult poultry, to characterize ground reaction forces (GRFs) produced in adult chickens during normal walking, and to assess the variability of GRFs.


METHODS
18 clinically normal 5-month-old Brown Leghorn hens.


METHODS
Vertical, craniocaudal, and mediolateral GRFs were measured as hens walked across a standard force plate embedded in the middle of a runway.


RESULTS
All GRFs were significantly affected by speed, and variability was high. With increasing speed, overall stance time decreased, but the percentage of stance time spent in braking or propulsion remained approximately equal. There was an overall increase in maximum propulsion force, which was produced at a greater rate over a shorter time; thus, propulsion integral decreased. Maximum braking forces and braking integrals were variable, but the rate at which the forces were generated increased. Mediolateral forces were 2 to 3 times greater in hens than values that have been reported for other species.


CONCLUSIONS
A standard force plate can be used to objectively measure GRFs in walking adult hens; however, the large variation in the data suggests that the technique in its current form would be of limited clinical use. Overall, vertical and craniocaudal forces had similar characteristics to those of other species, whereas mediolateral forces were found to be much greater in chickens than for other species.
Corr
Sandra A
SA
Department of Small Animal Medicine and Surgery, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts AL9 7TA.
McCorquodale
Caroline C
CC
McGovern
Rod E
RE
Gentle
Mike J
MJ
Bennett
David
D
D000818:Animals; D002645:Chickens / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D007794:Lameness, Animal; D011897:Random Allocation; D014743:Videotape Recording; D016474:Weight-Bearing / Q000502:physiology