Differences in bone turnover markers and injury risks between local and international horses: A Victorian Spring Racing Carnival study.

Ayodele, BA
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Pagel, CN
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Mackie, EJ
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Armour, F
·
Yamada, S
·
Zahra, P
·
Courtman, N
·
Whitton, RC
·
Hitchens, PL

Abstract: Musculoskeletal injuries (MSI) are common in racehorses and have been of increasing concern in horses travelling internationally to compete. Understanding the differences in bone turnover between local horses and international horses following long-distance air transportation may inform MSI prevention strategies. Objective: To understand the differences in bone turnover markers and risk of MSI between local horses and international horses following long-distance air transportation. Methods: Prospective cohort. Methods: The concentrations of bone turnover markers (OCN and CTXI), markers of stress (cortisol), inflammation (serum amyloid A) and circadian rhythm (melatonin), and bisphosphonates were determined in blood samples collected twice (14-17 days apart), from horses following international travel (n = 69), and from local horses (n = 79). The associations between markers, long-distance travel and MSI were determined using multivariable generalised linear regression models. Results: Within 3-5 days post-transport, concentrations of cortisol in international horses were higher than those of local horses (main effect, Coef. 0.39; 95% CI 0.24, 0.54; p < 0.001) but they decreased and were not different to those of local horses at the second timepoint (interaction effect, Coef. -0.27; 95% CI -0.46, -0.07; p = 0.007). After adjusting for age and sex, OCN and CTXI were not significantly different between international and local horses; however, OCN was lower in international horses at timepoint 2 (interaction effect, Coef. -0.16; 95% CI -0.31, -0.01; p = 0.043). The prevalence of MSI was higher in the international (26%; 95% CI 16, 38%) compared with local horses (8%; 95% CI 3, 16%; p < 0.001), with all severe MSI sustained by the international horses. At the second timepoint compared with the first timepoint post-transport, cortisol remained high or increased (interaction effect, Coef. 0.43; 95% CI 0.24, 0.61; p < 0.001) and OCN increased (interaction effect, Coef. 0.26; 95% CI 0.08, 0.44; p = 0.006) in the horses that sustained severe MSI. Conclusions: Horse population and racing career parameters differed between groups. Bone turnover markers have low sensitivity to detect local bone changes. Conclusions: Most horses showed minimal effects of long-distance air transport within 2 weeks relative to local horses as assessed by stress and bone turnover markers. Screening for persistent high cortisol and evidence of net bone formation after long-distance air transportation may help to identify racehorses at high risk of catastrophic MSI. Background: Les blessures musculosquelettiques (MSI) sont communes chez les chevaux de course et demeurent une source d'inquiétude pour les chevaux voyageant à l'international. Comprendre les différences de remodelage osseux entre les chevaux locaux et ceux voyageant suivant un trajet aérien longue distance pourrait aider au développement de stratégies de prévention des dommages musculosquelettiques. Objective: Comprendre les différences de marqueurs de remodelage osseux et de risques de MSI entre les chevaux locaux et ceux voyageant à l'international suivant un transport aérien de longue distance. TYPE D'ÉTUDE: Étude de cohorte prospective. MÉTHODES: Les concentrations des marqueurs de remodelage osseux (OCN et CTXI), de stress (cortisol), d'inflammation (serum amyloid A), de rythme circadien (melatonin) et les bisphosphonates ont été mesurés dans des échantillons sanguins à deux reprises (14–17 jours à part) chez des chevaux ayant été à l'international (n = 69) et étant restés localement (n = 79). L'association entre les marqueurs, le transport longue distance et les MSI a été déterminée par modèles de régression linéaire multivarié généralisé. RÉSULTATS: Entre 3 à 5 jours suivant le transport, les concentrations de cortisol chez les chevaux internationaux étaient supérieures aux chevaux locaux (effet primaire, Coef. 0.39; 95% CI 0.24, 0.54; P < 0.001), mais ont diminué par la suite jusqu'à ne plus être différent de ceux des chevaux locaux à la deuxième mesure (effet interaction, Coef. −0.27; 95% CI −0.46, −0.07; P = 0.007). Après ajustement pour l'âge et le sexe, OCN et CTXI n'étaient pas significativement différents entre les chevaux internationaux et locaux. Cependant, OCN était inférieur chez les chevaux internationaux à la deuxième mesure (effet interaction, Coef. −0.16; 95% CI −0.31, −0.01; P = 0.043). La prévalence de MSI était plus élevée chez les chevaux internationaux (26%; 95% CI 16, 38%) comparativement aux chevaux locaux (8%; 95% CI 3, 16%; p < 0.001), avec toutes les MSI sévères subi par les chevaux internationaux. Au moment de la deuxième mesure comparée à la première mesure après le transport, le cortisol est demeuré élevé ou a augmenté (effet interaction, Coef. 0.43; 95% CI 0.24, 0.61; P < 0.001) et l'OCN a augmenté (effet interaction, Coef. 0.26; 95% CI 0.08, 0.44; P = 0.006) chez les chevaux ayant subi une MSI sévère. Unassigned: La population équine et leurs paramètres de course diffèrent entre les groupes. Les marqueurs de remodelage osseux ont une faible sensibilité pour la détection de changements osseux localisés. Conclusions: En deux semaines, les effets de transport aérien longue distance ont été minimaux pour la majorité des chevaux comparativement aux chevaux locaux, tel que démontré par les marqueurs de stress et de remodelage osseux. La détection de niveau élevé de cortisol de façon persistante et d'évidence d'os néoformé suivant un transport aérien de longue distance pourrait aider à détecter les chevaux de course à haut risque de MSI.

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Publication Date: 2024-04-18 PubMed ID: 38634210DOI: 10.1111/evj.14098Google Scholar: Lookup

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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This study investigates the difference in bone turnover and the risk of musculoskeletal injuries (MSI) between local racehorses and international racehorses that have been subjected to long-distance air transportation. Results suggest that long-distance transportation may increase stress levels and cause bone changes in horses, leading to a higher risk of severe MSI in international horses compared to local ones.

Study Method

The research was a prospective cohort study.
Blood samples were taken from 69 international horses and 79 local horses twice, with a gap of 14-17 days between each sample collection.
The blood samples were analyzed for the levels of bone turnover markers (OCN and CTXI), stress marker (cortisol), inflammation marker (serum amyloid A), circadian rhythm marker (melatonin), and bisphosphonates.
Associations between these markers, long-distance travel, and MSI were determined using multivariable generalised linear regression models.

Results

Three to five days post-transport, stress levels (cortisol concentrations) in international horses were higher than those in local horses, but normalised by the second timepoint (14-17 days post-transport).
After adjusting for age and gender, bone turnover markers OCN and CTXI were not significantly different between international and local horses. However, OCN was lower in international horses at the second timepoint.
Severe MSI was more common in international horses, with a prevalence of 26%, compared to local horses, with a prevalence of 8%.
For horses that sustained severe MSI, cortisol levels remained high or increased and OCN levels also increased at the second timepoint compared to the first.

Conclusion

Horse population and racing career parameters differed between groups.
Bone turnover markers have low sensitivity in detecting local bone changes.
Most horses showed minimal effects of long-distance air transport within two weeks, relative to local horses, as assessed by stress and bone turnover markers.
Screening for persistently high cortisol levels and evidence of net bone formation after long-distance air transportation may help to identify racehorses at high risk of catastrophic MSI.

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APA

Ayodele BA, Pagel CN, Mackie EJ, Armour F, Yamada S, Zahra P, Courtman N, Whitton RC, Hitchens PL. (2024). Differences in bone turnover markers and injury risks between local and international horses: A Victorian Spring Racing Carnival study. Equine Vet J. https://doi.org/10.1111/evj.14098

Publication

Equine veterinary journal

ISSN: 2042-3306

NlmUniqueID: 0173320

Country: United States

Language: English

Researcher Affiliations

Ayodele, Babatunde A

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Pagel, Charles N

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Mackie, Eleanor J

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Armour, Fiona

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Yamada, Sean

Racing Analytical Services Limited, Flemington, Victoria, Australia.

Zahra, Paul

Racing Analytical Services Limited, Flemington, Victoria, Australia.

Courtman, Natalie

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Whitton, R Chris

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Hitchens, Peta L

Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Victoria, Australia.

Grant Funding

Racing Victoria
State Government of Victoria
University of Melbourne

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