Tend and Befriend in Horses: Partner Preferences, Lateralization, and Contextualization of Allogrooming in Two Socially Stable Herds of Quarter Horse Mares.
Authors: Kieson Emily, Goma Amira A, Radi Medhat
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Allogrooming—mutual scratching between horses—represents a measurable indicator of genuine social bonding rather than mere proximity tolerance, with distinct patterns emerging between relaxed and stressful environments. Researchers observed two separate herds of Quarter Horse mares (85 and 115 individuals respectively) across both pasture and confined settings, recording over 38 hours of footage to quantify allogrooming frequency, duration, lateralization (use of specific visual fields), and partner selectivity. Whilst pasture settings yielded only six allogrooming bouts averaging 163 seconds each, confined conditions triggered a dramatic 20-fold increase in sessions (118 total) albeit with markedly shorter durations of approximately 41 seconds—a statistically significant difference suggesting horses intensify affiliative contact with preferred partners during stress (p <0.01). Every allogrooming interaction involved consistent one-to-one pairings, indicating genuine friendships rather than random social grooming, and supporting the "tend and befriend" stress-response model previously documented in other species. For practitioners managing horse welfare, these findings validate that social stress relief mechanisms merit consideration in facility design and turnout protocols; horses demonstrating frequent but brief grooming interactions during confined periods may be displaying adaptive coping strategies rather than sufficient socialisation.
Read the full abstract on PubMed
Practical Takeaways
- •Allowing mares turnout time in pasture settings may support longer, more relaxed social bonding compared to confined conditions
- •Recognize that increased allogrooming frequency in confined/stressful situations is a normal stress-coping behavior and indicates social bonding rather than pathology
- •Consider maintaining stable social groupings of preferred partners when housing horses in confined conditions to support welfare through affiliative behaviors
Key Findings
- •Pasture setting produced 6 allogrooming sessions (avg 163.11s duration) vs. 118 sessions in confined settings (avg 40.98s duration)
- •Allogrooming frequency, duration, and number of pairs showed significant differences between pasture and confined settings (p < 0.01)
- •All allogrooming involved pairs of favored conspecifics demonstrating partner preference and social bonding
- •Horses demonstrate shorter but more frequent affiliative interactions during stress, supporting 'tend and befriend' social strategy