Quantifying the Impact of Mounted Load Carrying on Equids: A Review.
Authors: Bukhari Syed S U H, McElligott Alan G, Parkes Rebecca S V
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Working equids in developing countries—numbering approximately 112 million—frequently encounter welfare challenges linked to excessive loading and unsuitable working conditions, particularly around brick kilns, making evidence-based load-carrying capacity standards essential for both performance and animal welfare. This comprehensive review synthesised current knowledge on quantifying equids' loading capabilities, examining how traditional approaches (such as bone measurements) have evolved toward more sophisticated physiological and biomechanical markers. Key findings indicate that gait symmetry and stride parameter analysis offer valuable insights into loading adaptations, whilst recovery heart rate (rather than absolute heart rate alone) provides more accurate fitness assessment; additionally, biochemical indicators including plasma lactate, serum creatine kinase activity, and oxidative stress reliably reflect loading tolerance, with emerging evidence suggesting salivary cortisol correlates with thermal stress responses. For equine professionals managing working animals, these findings suggest implementing standardised gait analysis and post-work recovery protocols rather than relying solely on traditional "bone" measurements, though the authors stress that further research is urgently needed to establish evidence-based, species-appropriate load cut-offs that can be practically applied across diverse working settings. Without such standardisation, the welfare risks facing the vast population of working equids—particularly donkeys and horses in resource-limited regions—remain difficult to objectively quantify and mitigate.
Read the full abstract on PubMed
Practical Takeaways
- •Use gait analysis and heart rate recovery (not resting heart rate) as practical field tools to monitor if individual horses and donkeys are being overloaded
- •Multiple assessment methods—physiological, biochemical, and biomechanical—should be combined to establish safe, evidence-based load limits for working equids
- •Standardized load-carrying capacity guidelines are currently lacking and urgently needed for working equids in developing countries to improve welfare outcomes
Key Findings
- •Approximately 112 million working equids in developing countries are at risk, with many associated with brick kilns and overloading-related welfare issues
- •Gait symmetry and stride parameter analysis are reliable markers for assessing loading capacity and adaptations to load
- •Heart rate recovery post-work is a superior indicator of load-carrying capacity compared to absolute heart rate values
- •Oxidative stress, plasma lactate, serum creatine kinase, and salivary cortisol are biochemical indicators that can assess loading ability in working equids