Figure 1.
Position of reflective markers for kinematic data collection from a broiler chicken.
Figure 2.
Plan view of the runway set-up to capture kinematic gait data from test birds.
Four Qualisys ProReflex® cameras were aimed down the runway at the test bird (wearing reflective markers) located within the calibrated space. The test bird is located in the start position, facing a food reward and social cue (provided by two pen mates partitioned behind a net screen).
Figure 3.
Example of a typical segment of kinematic data illustrating the spatial and temporal progression of the reflective markers from a single broiler as it moved along the runway.
(a) Alternating right (R) and left (L) steps with (flat) stance and swing phases evident. The y co-ordinate (y-axis) represents the craniocaudal location of the leg marker spatially (‘0′ being the mid-point of the runway), while the x-axis represents time (t); (b) vertical back (VB) and vertical leg (VL) displacement; (c) lateral back displacement (LB) viewed from above. The letters with subscripts (R,L and X) denote examples of reference points that are used in calculating the various kinematic variables (as defined in Table 1).
Table 1.
Calculations for kinematic variables (gait parameters) using the example reference points detailed in Figure 3.
Table 2.
Group mean, S.D., and coefficient of variation (%CV) values for a series of gait parameters (calculated using individual mean values): jungle fowl (immature, JF1; adult, JF2, n = 10), non-lame broilers (GS0, n = 10) and lame-broilers (GS3, n = 12).
Figure 4.
Differences in gait parameter between four avian groups.
(a) stride duration, SD, (b) relative stride length, SL, (c) percentage stance, ST, (d) double-leg support, DS, (e) relative vertical leg displacement, VL, (f) relative lateral back displacement, LB, (g) relative vertical back displacement, VB.
Table 3.
Differences in gait parameter (Gait) between jungle fowl, (juvenile, ‘JF1’, and mature, ‘JF2’, n = 10), non-lame broilers, ‘GS0’ (n = 10), and lame broilers, ‘GS3’ (n = 12).
Table 4.
Summary of gait characteristics and rankinga (according to significance testing, Table 3, and data models, Figure 4) for four avian groups: immature jungle fowl (JF1), adult jungle fowl (JF2), non-lame broilers (GS0), and lame broilers (GS3).