Data from: Exploring the effects of giraffe skin disease limb lesions on locomotion
Data files
Jul 23, 2025 version files 12.37 KB
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Giraffe_Gait_Data.csv
9.65 KB
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README.md
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Abstract
Emerging skin diseases have severely impacted wildlife in recent decades with consequences ranging from increased morbidity and mortality to local extinction and widespread biodiversity loss. Individuals that persist with various skin diseases can have sublethal consequences including altered behavior and impaired locomotor function. Giraffe skin disease (GSD) is a condition that results in skin lesions of varying severity among different giraffe (Giraffa spp.) populations throughout Africa. Prior reports have suggested that individuals with limb lesions from GSD do not have increased mortality but rather suffer from lameness. We examined whether GSD severity and unilateral vs. bilateral forelimb lesions differentially impact spatiotemporal gait kinematics and carpus joint angle kinematics of Masai giraffe (G. tippelskirchi tippelskirchi) in Ruaha National Park, Tanzania. We found that GSD lesions altered normal walking gait kinematics (i.e., decreased walking speed and increased stride duration) largely irrespective of lesion severity or number of limbs affected. Impaired movement due to GSD could negatively impact foraging efficiency, dispersal, and predator susceptibility. Given that wildlife skin diseases are predicted to become more prevalent with climate change, examinations of their sublethal effects, in addition to their effects on mortality, are required to better understand long-term ramifications.
Dataset DOI: 10.5061/dryad.qbzkh18vg
Description of the data and file structure
This file contains data on spatiotemporal limb kinematics and carpus joint angle kinematics.
Files and variables
File: Giraffe_Gait_Data.csv
Description:
Variables
- Animal_ID: Individual identification number of animal
- Sex: assigned female or male
- Video_Number: identifying feature of video
- Frame_Number: video frame number designating the start of the stride
- Lesion_Score: scored as absent, mild, or moderate/severe
- Legs_Affected: indicates whether the right forelimb (RF) and/or left forelimb (LF) had skin lesions; NA indicates that neither leg was affected
- Area_Affected: includes area where lesions were present (i.e., radioulna, carpus joint, and/or metacarpal). Individuals lacking discernible lesions were scored as “healthy”
- Relative_Stride_Length: Relative stride length was calculated by dividing stride length in pixels by shoulder height in pixels
- Mean_Stride_Duration: Stride duration was recorded as the duration (in seconds) between the initial and subsequent touchdown of a reference limb. Mean stride duration was generated based on the values for each of the four limbs.
- Relative_Speed: Relative speed was calculated by dividing relative stride length by mean stride duration, resulting in values with units of % of shoulder height per second.
- Mean_NSL: We quantified the portion of stride duration in which individuals were supported by zero, one, two, three or four limbs, to generate mean number of supporting limbs (i.e., mean NSL) throughout the stride.
- Peak_Flexion: We digitized carpus angle in each video frame using ImageJ and identified peak flexion. NA indicates that carpus angle was not digitized for this video due to parallax concerns.
- Peak_Extension: We digitized carpus angle in each video frame using ImageJ and identified peak extension. NA indicates that carpus angle was not digitized for this video due to parallax concerns.
- ROM: We then calculated carpus angle range of motion (ROM) as the difference between peak flexion and peak extension. NA indicates that carpus angle was not digitized for this video due to parallax concerns.
Code/software
We used GaitKeeper, an open-source MATLAB package, to digitize limb liftoff and touchdown events, shoulder height, and stride length (Dunham et al. 2018) (http://www.younglaboratory.org/GaitKeeper). We recorded neck angle measurements for individual videoframes using the angle tool in ImageJ (Rueden et al. 2017).