Authors: Giles Sarah L, Nicol Christine J, Harris Patricia A, Rands Sean A
Journal: Applied animal behaviour science
Summary
# Editorial Summary: Dominance, Body Condition and Social Rank in Group-Living Horses When 203 horses across 42 outdoor herds were observed during feeding tests, researchers systematically ranked individuals by dominance behaviour and assessed their body condition scores on a nine-point scale, controlling for age and height as potential confounders. The data revealed a striking association: more dominant horses maintained significantly higher body condition scores and were disproportionately represented in the obese category (BCS ≥7/9), with this relationship holding independently of age or physical size. Peak dominance occurred in middle-aged individuals, whilst herds with greater variation in age and height showed reduced aggression and competitive interactions—suggesting that phenotypic diversity may naturally buffer social tension. These findings represent the first direct evidence linking social hierarchy to obesity risk in horses, highlighting an important gap in how we assess disease susceptibility in group-living animals. For practitioners managing herds, this research underscores that behavioural assessment and social dynamics warrant consideration alongside traditional nutritional and metabolic evaluations when addressing weight management and associated health risks.
Read the full abstract on PubMed
Practical Takeaways
- •When managing group-housed horses, recognize that dominant individuals are at higher risk of obesity regardless of age or size, requiring targeted feeding management strategies
- •Consider social dynamics and dominance hierarchy when assessing body condition problems in herds, as behavioural factors may be driving obesity risk
- •Monitor middle-aged horses more closely for obesity and overfeeding issues, as they are most likely to occupy dominant positions with associated higher body condition
Key Findings
- •More dominant horses had significantly higher body condition scores (p = 0.001), independent of age and height
- •A greater proportion of dominant individuals were obese (BCS ≥ 7/9, p = 0.005)
- •Middle-aged horses showed the strongest dominance rank with a quadratic age-dominance relationship (p < 0.001)
- •Herds with less phenotypic variation in age and height showed more displacement encounters and greater interactivity