Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon.
Am J Primatol. 2019 Aug;81(8):e23031. doi: 10.1002/ajp.23031. Epub 2019 Jul 30.
Pair housing is considered one of the best ways of promoting psychological wellbeing for caged macaques. However, incompatible partnerships can result in stress or aggression. Though previous studies have analyzed the role of variables such as age, weight, gender, and temperament on pair compatibility, few have examined the relationship between physiological parameters and pair compatibility. Oxytocin is known to promote prosocial nonsexual behavior in various primate species and may serve as an indicator of pair compatibility. In this study, we examined the association between peripheral oxytocin levels and prosocial behaviors in isosexual pairs of male rhesus macaques. We hypothesized that animals that demonstrated high levels of prosocial behaviors would have higher oxytocin levels than those showing low levels of the behavior. In addition, to elucidate the relationship between oxytocin and compatibility, we compared peripheral oxytocin between the highly affiliative animals and single-housed males identified as having multiple unsuccessful pair attempts with multiple partners. We collected plasma oxytocin on 40 pairs of monkeys that had lived together for at least 1 month and 20 single-housed animals. Further, we simultaneously collected behavioral data on the pairs, recording prosocial interactions (e.g., groom, play). Oxytocin varied among individuals, but was highly correlated between members of a pair (r = 0.58, p < .001). Additionally, prosocial behavior was positively correlated with plasma oxytocin (r = 0.38, p < .02). However, contrary to our expectations, oxytocin did not differ between single and highly affiliative pair-housed animals (F = 0.71, p = .40). Our results suggest that oxytocin may be associated with the quality of isosexual pairs of male macaques. More work is needed to determine the nature of this relationship.
对笼养猕猴而言，配对饲养被认为是增进其心理健康的最佳方式之一。然而，不兼容的伴侣关系可能会导致压力或攻击行为。尽管先前的研究分析了年龄、体重、性别和气质等变量对配对兼容性的作用，但很少有研究检验生理参数与配对兼容性之间的关系。催产素已知可促进各种灵长类动物的亲社会非性行为，并且可以作为配对兼容性的指标。在这项研究中，我们检验了雄性恒河猴同性别配对中催产素与亲社会行为之间的关联。我们假设，表现出高水平亲社会行为的动物的催产素水平会高于表现出低水平亲社会行为的动物。此外，为了阐明催产素与兼容性之间的关系，我们比较了具有高度亲和力的动物和被鉴定为多次与多个伴侣配对尝试均未成功的单只饲养雄性动物的外周催产素水平。我们收集了至少共同生活 1 个月的 40 对猴子的血浆催产素和 20 只单只饲养动物的外周催产素。此外，我们同时对这些配对动物的行为数据进行了采集，记录了亲社会互动（例如，梳理毛发、玩耍）。催产素在个体之间存在差异，但在配对动物的成员之间具有高度相关性（r=0.58，p<0.001）。此外，亲社会行为与血浆催产素呈正相关（r=0.38，p<0.02）。然而，与我们的预期相反，单只饲养动物和具有高度亲和力的配对饲养动物的外周催产素没有差异（F=0.71，p=0.40）。我们的研究结果表明，催产素可能与雄性猕猴的同性别配对的质量有关。需要进一步的工作来确定这种关系的性质。
