Social facilitation of trotting: Can horses perceive and adapt to the movement of another horse?
Authors: Bogossian Paulo Moreira, Pereira Juliana Santos, da Silva Nathalia Felicio, Hilgert Ayrton Rodrigo, Seidel Sarah Raphaela Torquato, Fülber Joice, Belli Carla Bargi, Fernandes Wilson Roberto
Journal: PloS one
Summary
# Editorial Summary Researchers investigating whether horses adjust their exercise intensity in response to observing another horse exercised seven horses on a treadmill whilst displaying either a video of a trotting horse or a control image of an empty racetrack. During the two-minute visual stimulus period, horses viewing the trotting horse demonstrated significantly elevated heart rates (130.8 versus 84.7 b.p.m.), plasma lactate concentrations (5.28 versus 3.27 mg/dl), and head elevation angles (36.43° versus 25.14°), alongside markedly increased forward ear posture (100% versus 14% of subjects). These physiological and postural changes indicate that horses perceived the competing equine stimulus and shifted into a more engaged, vigilant state, activating anaerobic metabolic pathways without signs of distress. For practitioners working with horses, these findings suggest that social facilitation—using visual or physical presence of other moving horses—offers a practical, welfare-friendly alternative to encourage forward movement and increased exercise intensity, potentially reducing reliance on artificial aids such as the whip whilst harnessing naturally occurring behavioural responses.
Read the full abstract on PubMed
Practical Takeaways
- •Displaying images or using another horse during exercise can naturally increase exercise intensity without physical punishment—heart rate and lactate increased significantly in response to visual social stimulus
- •Horses perceive and respond behaviorally to social cues; using social facilitation (exercising alongside another horse or visual representation) may improve forward movement and work engagement
- •This validated, gentler approach to encouraging forward movement offers an alternative to whip use, potentially improving horse welfare and training efficacy
Key Findings
- •Heart rate increased from 84.7±15.1 to 130.8±27.8 b.p.m. (P=0.017) when horses viewed video of another trotting horse versus control racetrack image
- •Plasma lactate increased from 3.27±1.24 to 5.28±1.48 mg/dl (P=0.042) with visual horse stimulus, indicating shift to anaerobic metabolism
- •Head angle elevated from 25.14±4.88° to 36.43±3.69° (P=0.003) with visual stimulus, reflecting increased vigilance and attention
- •Ears-forward behavior occurred in 100% of horses (7/7) with visual stimulus versus 14% (1/7) with control, indicating heightened alertness