Influence of full-time housing in vector-protected facilities on equine cortisol levels, heart rate, and behavior during the African horse sickness outbreak in Thailand

ABSTRACT

Horses were provided full-time housing in unfamiliar vector-protected facilities during the African horse sickness (AHS) outbreak in Thailand. This study aimed to investigate the impact of this housing arrangement on the equine stress response. Nine healthy horses were housed in both a traditional barn and a vector-protected barn. Equine behavior and stress response data were collected in association with the housing environment and time of day. The mean behavioral score of horses housed in the vector-protected barn was lower at night than during the day. In addition, the horses’ mean heart rate at night was lower than their heart rate during the day, irrespective of housing condition. Furthermore, although blood cortisol peaked at 6:00 AM and was lowest at 6:00 PM under both housing conditions, daily fluctuations in blood cortisol levels were correlated with changes in humidity and temperature in both environments. Finally, horses housed in the traditional barn exhibited earlier decreases in cortisol levels relative to the horses in the vector-protected barn. This result indicates that housing horses in vector-protected facilities may impose stress.

KEYWORDS:

• Cortisol
• horse
• humidity
• stress
• vector-protected facilities
• welfare

Acknowledgments

We are grateful to Miss Vaewratt Kamonkon, director of the Horse Lover’s Club, to allocate her horses and housing facilities for this study. We also thank the clinical chemistry section, Thai Vet Lab Co., Ltd., for serum cortisol determination.

Authors’ contributions

WJ and CP: study design, sample collections, data analysis, and interpretation. PT and PC: sample collections, data analysis, and interpretation. MC: study design, sample collections, data analysis, and interpretation, drafted and revised the manuscript. All authors had access to all data and approved the manuscript.

Ethical statement

The Ethics Committee for Animal Experiments of Kasetsart University (ACKU63-VET-036) approved all procedures involving animals.

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Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.