Loftus Loni, Newman Amy, Leach Matthew, Asher Lucy
School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
Royal (Dick) School of Veterinary Studies and the Roslin Institute, Easter Bush Campus, University of Edinburgh, Midlothian, EH25 9RG, UK.
Sci Rep. 2025 May 27;15(1):18550. doi: 10.1038/s41598-025-98034-8.
There is increasing focus on how to induce and measure positive affective states in animals and the development of social license to operate has brought this to the forefront within equestrianism. This study aimed to utilise a range of methods to induce and measure positive affect in horses in real-world settings. Twenty healthy horses were scored for personality, exposed to four induction methods (wither scratching, high value food provision, positive reinforcement training and the addition of an affiliative conspecific), and data collected on their behaviour (QBA and ethograms) and physiology (heart and respiratory rate, heart rate variability, eye and ear thermography and salivary cortisol). Analyses identified potentially sensitive and specific behavioural (ear and eye position, QBA items, frustration items) and physiological (RR mean, HF power, LF power, LF/HF ratio, mean HR, RMSSD and pNN50) measures of affective state across the four quadrants of core affect. Individual difference effects were found, and personality traits such as unfriendly, nervous and unresponsive were associated with differing responses to induction stimuli indicating that all four induction stimuli are potentially useful for inducing positive affect depending on their salience to the individual. Research measuring and inducing positive affect in animals rarely considers personality, but this study underscores its importance. The dimensional approach taken allowed for assessment of the broad arousal and valence components of affect without ascribing measures to discrete emotions. Accurate, real-world measures of affect could benefit 116 million equines globally, and exploring ways to promote positive affect in horses can significantly enhance their welfare.
人们越来越关注如何在动物中诱导和测量积极的情感状态，而社会运营许可的发展已将这一问题推到了马术领域的前沿。本研究旨在运用一系列方法，在现实环境中诱导和测量马匹的积极情感。对20匹健康马匹进行了性格评分，使其接受四种诱导方法（挠肩胛、提供高价值食物、正面强化训练以及添加友好的同种动物），并收集了它们的行为（定性行为评估和行为图谱）和生理数据（心率和呼吸率、心率变异性、眼耳热成像以及唾液皮质醇）。分析确定了在核心情感的四个象限中，情感状态的潜在敏感和特定行为（耳朵和眼睛位置、定性行为评估项目、挫折项目）及生理（平均呼吸率、高频功率、低频功率、低频/高频比值、平均心率、相邻RR间期差值的均方根以及pNN50）指标。发现了个体差异效应，诸如不友好、紧张和无反应等性格特征与对诱导刺激的不同反应相关，这表明根据对个体的显著性，所有四种诱导刺激都可能有助于诱导积极情感。测量和诱导动物积极情感的研究很少考虑性格，但本研究强调了其重要性。所采用的维度方法允许在不将测量结果归因于离散情绪的情况下，评估情感的广泛唤醒和效价成分。准确的现实环境情感测量可能使全球1.16亿匹马受益，探索促进马匹积极情感的方法可显著提高它们的福利。
