Frontiers in veterinary science2026; 13; 1927282; doi: 10.3389/fvets.2026.1927282

Behavioral changes in thoroughbred horses following pre-training: insights from novel object tests and activity monitoring under field conditions.

Pinetzki, L
·
Menze, J
·
Eichler, F
·
Brüsewitz, I
·
Engler, T
·
Stutzke, S
·
Merle, R
·
Hoffmann, G
·
Wiegard, M
·
Thöne-Reineke, C
·
Kirsch, K

Abstract: Racehorse training starts with pre-training, which is conducted at a very early age and remains controversial from an animal welfare perspective. This study investigated how a 12-week pre-training program influenced the behavior of young Thoroughbred horses. Horses were assessed before (A) and after (B) pre-training, which progressed from habituation and handling to ridden exercise and canter work on a racetrack. Behavioral responses were evaluated using standardized novel object tests and continuous 24-h stall monitoring via inertial measurement unit sensors. Novel object test behavior was video-recorded and analyzed using a validated ethogram comprising 34 behavioral parameters. Following pre-training, horses showed significantly increased locomotor activity during novel object tests, including longer durations of trot (A: 16.1 ± 6.7 s; B: 41.6 ± 6.7 s; < 0.01), gallop (A: 1.9 ± 1.6 s; B: 11.4 ± 1.6 s; < 0.001), and bucking (A: 1.0 ± 2.8 s; B: 22.2 ± 2.8 s; < 0.001). Tactile exploration also increased, reflected in more frequent muzzle contact with the object (A: 2.2 ± 0.8; B: 6.0 ± 2.0; < 0.05), despite a reduction in the total number of approaches (A: 8.1 ± 0.9; B: 6.3 ± 0.7; < 0.05), suggesting altered patterns of interaction with the novel object following pre-training. Stall behavior correlated with responses in the novel object test, supporting the consistency of individual behavioral tendencies across contexts. Principal component analysis revealed four main profiles: highly active/offensive behavior, exploratory engagement, vigilance/defensive behavior, and calm observation. Notably, inter-individual variability between individuals increased after pre-training. The shift toward increased locomotion and tactile exploration suggests adaptive behavioral modulation in response to early training. While some horses transitioned toward more active and confident profiles, others remained stable, indicating that certain traits may be inherent whereas others are experience-dependent. These findings highlight the importance of multidimensional behavioral assessment and demonstrate that integrating experimental and continuous monitoring approaches can improve the interpretation of novel object test responses and support evidence-based equine welfare assessment.

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Publication Date: 2026-09-21 PubMed ID: 42840463PubMed Central: PMC13639667DOI: 10.3389/fvets.2026.1927282Google Scholar: Lookup

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Conflict of Interest
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Journal Article

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.

Overview

This study examines how a 12-week pre-training program affects the behavior of young Thoroughbred horses.
Behavioral changes were evaluated using novel object tests and 24-hour activity monitoring under real-world conditions.

Research Background and Purpose

Pre-training in racehorses starts at an early age and involves gradual habituation to handling, ridden exercise, and track work.
This early training is controversial with regard to animal welfare, making it important to understand its behavioral effects.
The study aimed to measure how young Thoroughbred horses’ behaviors change following a standardized 12-week pre-training program.

Methods

Subjects: Young Thoroughbred horses undergoing a structured 12-week pre-training regimen.
Assessment Timepoints:
- Before pre-training (Timepoint A)
- After pre-training (Timepoint B)
Behavioral Measurements:
- Novel Object Tests:
  - Horses exposed to unfamiliar objects to observe behavioral responses.
  - Sessions video recorded and analyzed with an ethogram detailing 34 behavioral parameters.
- Stall Monitoring:
  - Continuous 24-hour activity recorded using inertial measurement units (IMUs).
  - Allows observation of natural behaviors in a home environment.

Key Findings

Increased Locomotor Activity Post-Training:
- Trot duration increased significantly (from about 16s to 42s).
- Gallop duration increased substantially (from 2s to 11s).
- Bucking also rose markedly (from 1s to 22s).
Changes in Interaction with Novel Objects:
- Tactile exploration increased, shown by more frequent muzzle contacts with the object.
- The total number of approaches to the object decreased, indicating a change in how horses engaged with the novel item.
- These results suggest that horses became more confident but more selective in their interactions.
Correlation Between Stall and Novel Object Behaviors:
- Behavioral tendencies observed in the stable environment correlated with responses to novel objects, indicating consistent individual traits.
Behavioral Profiles Identified via Principal Component Analysis (PCA):
- Highly active/offensive behavior
- Exploratory engagement
- Vigilance/defensive behavior
- Calm observation
Increased Inter-Individual Variability:
- Post-training, horses showed greater diversity in behavior patterns.
- Some horses became more active and confident while others remained behaviorally stable.
- This suggests that certain behavioral traits are innate, while others develop through experience.

Interpretation and Implications

The increased locomotion and exploratory behavior post-pre-training indicates that early exposure to handling and exercise can modulate behavioral responses adaptively.
Variability among horses implies that pre-training affects individuals differently, influenced by inherent temperament and learning.
The integration of experimental novel object tests with continuous stall monitoring offers a comprehensive approach to assessing behavior.
These methods enhance the understanding of how training impacts welfare by revealing nuanced behavioral adaptations.
The study underscores the importance of multidimensional behavioral assessments in making science-based decisions to optimize horse welfare during early training phases.

Cite This Article

APA

Pinetzki L, Menze J, Eichler F, Brüsewitz I, Engler T, Stutzke S, Merle R, Hoffmann G, Wiegard M, Thöne-Reineke C, Kirsch K. (2026). Behavioral changes in thoroughbred horses following pre-training: insights from novel object tests and activity monitoring under field conditions. Front Vet Sci, 13, 1927282. https://doi.org/10.3389/fvets.2026.1927282

Publication

Frontiers in veterinary science

ISSN: 2297-1769

NlmUniqueID: 101666658

Country: Switzerland

Language: English

Volume: 13

Pages: 1927282

PII: 1927282

Researcher Affiliations

Pinetzki, Lara

Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany.

Menze, Jule

Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany.

Eichler, Fabienne

Department Sensors and Modeling, Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Potsdam, Germany.

Brüsewitz, Isabel

Institute of Movement and Training Science in Sports II, Leipzig University, Leipzig, Germany.

Engler, Tina

Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany.

Stutzke, Saskia

Department Sensors and Modeling, Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Potsdam, Germany.

Merle, Roswitha

Institute of Veterinary Epidemiology and Biostatistics, Freie Universität Berlin, Berlin, Germany.

Hoffmann, Gundula

Department Sensors and Modeling, Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Potsdam, Germany.

Wiegard, Mechthild

Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany.

Thöne-Reineke, Christa

Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany.

Kirsch, Katharina

Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany.

Conflict of Interest Statement

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author RM declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision.

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