First night effect alters occipital brain connectivity in horses.
Abstract: The First Night Effect is a phenomenon whereby sleep duration and quality are compromised in unfamiliar environments or situations. Horses are often transported to new locations, such as sporting events. We wanted to know if the First Night Effect is also detectable in horses in two different populations. To investigate this, we compared five horses from a professional sports horse barn that are regularly used in competitions, with six horses from a breeding barn, that are less frequently transferred to unfamiliar places. Despite the significant differences observed in electroencephalography (EEG) patterns and behavior between the two horse populations, we were able to identify EEG changes indicative of the First Night Effect. These changes were most apparent in the delta band at the occipital position of the brain, indicating fluctuations in sleep-wake dynamics and consciousness. Furthermore, in this study, EEG data outperformed behavioral data in the detection of the First Night Effect, indicating the usefulness of EEG measurements for monitoring welfare or even assessing stress and pain.
© 2025. The Author(s).
Publication Date: 2025-08-17 PubMed ID: 40820082PubMed Central: PMC12358621DOI: 10.1038/s41598-025-14830-2Google Scholar: Lookup
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Summary
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The research investigated the impact of unfamiliar environments on the sleep patterns of two different populations of horses, revealing that significant changes in their brain activity could be noted due to the First Night Effect.
Study Objective
- The study was aimed at determining whether the First Night Effect, a phenomenon that affects sleep quality and duration in unfamiliar environments, could be observed in horses that have been moved to new locations.
Research Methodology
- The researchers compared the behavior and electroencephalography (EEG) patterns of two different horse populations: one consisted of professional sport horses that regularly participated in competitions, while the other comprised breeding horses that were infrequently moved to unfamiliar places.
Findings
- Despite the differences in behaviour and EEG patterns between the two groups, researchers noticed that EEG changes indicative of the First Night Effect were visible.
- The changes were particularly noticeable in the horse’s occipital brain, marked by fluctuations in the delta band.
- This suggested an impact on the horse’s sleep-wake dynamics and consciousness.
Implications and Utility of the Research
- The study revealed that EEG data was more accurate than behavioural data in detecting the First Night Effect.
- This suggests that EEG measurements could be a valuable tool for monitoring horse welfare and assessing stress and pain levels.
- Thus, the study contributes crucial knowledge to understanding the impact of novel environments on animals, especially horses, and how such changes can be monitored effectively.
Cite This Article
APA
Bergeler J, Liske-Schmitz A, Schmitz T, de Camp NV.
(2025).
First night effect alters occipital brain connectivity in horses.
Sci Rep, 15(1), 30075.
https://doi.org/10.1038/s41598-025-14830-2 Publication
Researcher Affiliations
- Petesys UG (ltd), Hauptstraße 3a, Haseloff, Mühlenfließ, 14823, Brandenburg, Germany. Juergen.bergeler@petesys.de.
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Free University, Berlin, Germany. Juergen.bergeler@petesys.de.
- Equine rehabilitation center, Gut Marggraffshof GmbH, Marggraffshof 2, Marggraffshof , 14532, Brandenburg, Germany.
- Equine rehabilitation center, Gut Marggraffshof GmbH, Marggraffshof 2, Marggraffshof , 14532, Brandenburg, Germany.
- Petesys UG (ltd), Hauptstraße 3a, Haseloff, Mühlenfließ, 14823, Brandenburg, Germany. Nora.deCamp@petesys.de.
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Free University, Berlin, Germany. Nora.deCamp@petesys.de.
MeSH Terms
- Animals
- Horses / physiology
- Electroencephalography
- Sleep / physiology
- Behavior, Animal / physiology
- Male
- Brain / physiology
- Female
Grant Funding
- 13GW0033B / Bundesministerium fu00fcr Bildung und Forschung
- 03EFJBE108 / European Social Fund Plus
- 03EFJBE108 / Federal Ministry for Economic Affairs and Energy
Conflict of Interest Statement
Declarations. Competing interests: The company petesys will make the EEG system commercially available in the future, as well as EEG services. Furthermore, we have a european patent on the PEDOT polymer electrodes. All the remaining authors declare no conflict of interest.
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