Stable Microclimates and Autonomic Modulation in Horses Sin-Gle-Stall Housed in Different Stable Architectures During Mon-Soon in a Tropical Savannah Environment

The influence of climate conditions and stable design on horses housed in single stalls can have significant effects, especially in regions with tropical savannah climates. A recent study observed variations in autonomic responses in horses housed in different stable designs during the summer, but there is limited information about their conditions during the monsoon. This study investigated the stable microenvironment and autonomic regulation of horses housed in different stable archi-tectures during the monsoon in a tropical savannah environment. Twenty-two horses were allo-cated to one of three stable architectures, each with varying stable microenvironments. The findings reveal that the heart rate variability (HRV) was lower in horses in a stable with a solid external wall and lower volume-to-horse ratio compared to those in a stable with a solid external wall but a higher volume-to-horse ratio or one without a solid external wall. Additionally, the study found that stable microenvironments and HRV modulation were correlated with stable architecture. Autonomic responses differed among horses in different stable architectures, indicating that stable microen-vironments and, to some extent, volume-to-horse ratio play a role in horses’ autonomic regulation. The findings have implications for improvements in housing and welfare in tropical savannah environments.