Abstract:
While sheep can detect and discriminate human emotions through visual and vocal cues, their reaction to human body odors remains unknown. The present study aimed to determine whether sheep (Ovis aries) can detect human odors, olfactorily discriminate stressed from non-stressed individuals, and behave accordingly based on the emotional valence of the odors. Axillary secretions from 34 students were collected following an oral examination (stress odor) or a regular class (non-stress odor). Fourteen female and 15 male lambs were then exposed to these odors through a habituation-dishabituation procedure. The habituation stimulus was presented four times for one minute, followed by the dishabituation stimulus presented once for one minute. Behavioral variables included spatiality relative to target odors, approach/withdrawal, ear positioning, sniffing, ingestion, and vocalization. Both female and male lambs more often positioned their ears backwards/forwards, and asymmetrically when exposed to the dishabituation stimulus, but regardless of their stress or non-stress value. They also changed their approach behavior when exposed to the dishabituation stimuli. Lambs displayed some behavioral signs of discrimination between the habituation and dishabituation odors, but regardless of their relation to stress or non-stress of human donors. In sum, this exploratory study suggests that young sheep respond negatively to the odor of unfamiliar humans, without showing any specific emotional contagion related to the stress odor. This exploratory study suggests young ovines can detect human body odor, a further step toward understanding the human-sheep relationship.
摘要:
虽然绵羊可以通过视觉和声音线索来检测和辨别人类的情绪,他们对人体气味的反应仍然未知。本研究旨在确定绵羊(Ovisaries)是否可以检测到人类的气味,嗅觉上区分有压力的人和无压力的人,并根据气味的情绪效价做出相应的行为。在进行口腔检查(压力气味)或常规课程(非压力气味)后,收集了34名学生的腋窝分泌物。然后,通过习惯处理程序将14只雌性羔羊和15只雄性羔羊暴露于这些气味中。习惯刺激在一分钟内被呈现四次,接下来是一次一分钟的泄气刺激。行为变量包括相对于目标气味的空间性,接近/退出,耳朵定位,嗅探,摄取,和发声。雌性和雄性羔羊更经常将耳朵向后/向前定位,当暴露于泄气刺激时不对称,但不管他们的压力或非压力值。当暴露于泄气刺激时,他们也改变了他们的接近行为。羔羊表现出一些行为上的习惯性和食腐气味之间的歧视迹象,但不管它们与人类捐赠者的压力或非压力的关系。总之,这项探索性研究表明,幼羊对陌生人类的气味有负面反应,没有表现出任何与压力气味相关的特定情绪传染。这项探索性研究表明,年轻的绵羊可以检测到人体的气味,进一步了解人与羊的关系。