Vasconcellos Angélica da Silva, Virányi Zsófia, Range Friederike, Ades César, Scheidegger Jördis Kristin, Möstl Erich, Kotrschal Kurt
Program of Post-Graduation in Vertebrate Biology, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Institute of Psychology, University of São Paulo, São Paulo, São Paulo, Brazil.
PLoS One. 2016 Sep 9;11(9):e0162389. doi: 10.1371/journal.pone.0162389. eCollection 2016.
The welfare of animals in captivity is of considerable societal concern. A major source of stress, especially for wild animals, is the lack of control over their environment, which includes not being able to avoid contact with human beings. Paradoxically, some studies have shown that interactions with human beings may improve the welfare of wild animals in captivity. Here, we investigated the behavioural (behaviours indicative of cooperation or stress) and physiological (variations in salivary cortisol concentrations) effects of the increasingly used practice of training wild animals as a way to facilitate handling and/or as behavioural enrichment. We evaluated the effects of indoor training sessions with familiar caretakers on nine human-socialised individuals of a wild species, the wolf (Canis lupus), in comparison to nine individuals of its domesticated form, the dog (Canis lupus familiaris). All animals were raised and kept in intraspecific packs under identical conditions-in accordance with the social structure of the species-in order to control for socialisation with human beings and familiarity with training. We also collected saliva samples of trainers to measure GC and testosterone concentrations, to control for the effects of trainers' stress levels on the responses of the animals. During the training sessions, separated from pack members, the animals stayed voluntarily close to the trainers and mostly adequately performed requested behaviours, indicating concentration to the task. Similarly to dogs, the salivary cortisol level of wolves-used as an index of stress-dropped during these sessions, pointing to a similar stress-reducing effect of the training interaction in both subspecies. The responses to the requested behaviours and the reduction in salivary cortisol level of wolves and dogs varied across trainers, which indicates that the relaxing effect of training has a social component. This points to another factor affecting the welfare of animals during the sessions, beside the rewarding effect of getting food and control over the situation by successfully completing a task. As all responses performed by the animals corresponded to cues already familiar to them, the reported effects were likely due to the above cited factors rather than to a learning process. Our results support previous findings suggesting that training is a potentially powerful tool for improving welfare in some wild social canids by creating structured and positive interactions between these animals and their human caretakers.
圈养动物的福利是社会相当关注的问题。压力的一个主要来源，尤其是对野生动物来说，是它们无法控制自身环境，这包括无法避免与人类接触。矛盾的是，一些研究表明，与人类的互动可能会改善圈养野生动物的福利。在此，我们调查了越来越多地用于训练野生动物以方便处理和/或作为行为丰富手段的做法对行为（表明合作或压力的行为）和生理（唾液皮质醇浓度变化）的影响。我们评估了与熟悉的饲养员进行室内训练对一种野生动物——狼（Canis lupus）的九个已适应人类社会的个体的影响，并与它的家养形态——狗（Canis lupus familiaris）的九个个体进行比较。所有动物都按照物种的社会结构，在相同条件下以同种群体的方式饲养和生活，以控制与人类的社交以及对训练的熟悉程度。我们还收集了训练员的唾液样本，以测量糖皮质激素（GC）和睾酮浓度，以控制训练员压力水平对动物反应的影响。在训练期间，动物与群体成员分开，它们自愿靠近训练员，并大多能很好地完成要求的行为，这表明它们专注于任务。与狗类似，狼的唾液皮质醇水平——作为压力指标——在这些训练期间下降，这表明训练互动在两个亚种中都有类似的减轻压力的效果。狼和狗对要求行为的反应以及唾液皮质醇水平的降低因训练员而异，这表明训练的放松效果有社会因素。这指出了在训练期间影响动物福利的另一个因素，除了获得食物的奖励效果以及通过成功完成任务对情况的掌控之外。由于动物做出的所有反应都与它们已经熟悉的线索相对应，所报告的效果可能是由于上述因素，而不是学习过程。我们的结果支持了先前的研究发现，即训练是通过在这些动物与其人类饲养员之间建立结构化的积极互动来改善一些野生群居犬科动物福利的潜在有力工具。
