作为食肉目动物，大熊猫（Ailuropoda melanoleuca）在数百万年的进化中，通过形态、生态、遗传等多方面特化，逐渐形成主要食竹的习性。在不同季节，不同局域种群的大熊猫对所食竹子的种类和部位具有不同的选择偏好。这种选择可能与视觉、嗅觉、味觉等多种感官因素有关，然而具体选择机制尚不清楚。为探明嗅觉在大熊猫取食过程中的作用，本研究提出假说，认为大熊猫能够通过气味提供的嗅觉信号辨别竹子的不同种类和不同部位。然后通过气味辨别的行为实验和气相色谱-质谱联用（GC-MS）技术，探究了大熊猫对竹子气味的辨别能力及其物质基础。 本研究在仅提供气味信息的条件下，借助双向选择实验，对27只成年健康大熊猫的行为进行了观察记录。结果如下： 1. 选择不同种类的竹子两两配对，形成4种组合类型进行实验，结果显示大熊猫对竹子的气味没有选择偏好；选择竹子的不同部位进行配对时，大熊猫对竹笋的气味表现出明显的选择偏好。该结果部分支持了我们提出的嗅觉辨别假说，表明大熊猫能够通过气味辨别竹笋与竹茎，然而是否能通过气味辨别不同种类的竹子则需要进一步的实验验证。 2. 利用GC-MS技术对16种竹类样品的挥发性成分进行分析，共鉴定出33种化学物质。其中8种不同种类的竹茎所包含的物质较少，为0至5种不等；而竹叶所包含的物质较多，为13至20种不等；竹笋中包含11种化学物质，其中乙酸、正庚醛在本实验的竹茎和竹叶中均未检测到。判别分析可明显将不同样品分为竹叶、竹茎、竹笋3类；主成分分析也可将三者分开，且不同种类的竹叶之间挥发性成分差异较大。 本研究表明，大熊猫可以根据气味辨别竹子的竹笋和竹茎，其物质基础可能是不同部位之间挥发性成分的差异；不同种类的竹叶之间挥发性成分差异较大，然而大熊猫在行为学层面并未表现出对不同种类的选择偏好，其原因有待进一步验证。该结果有助于了解大熊猫的摄食偏好以及圈养种群的饲养管理。

The giant panda (Ailuropoda melanoleuca) is a carnivorous species which has a specialized bamboo diet over millions of years’ evolution with morphological, ecological and genetic adaptations. They show preference to different species and different parts of bamboo in different seasons each year. It proposed that their selection of bamboo may be related with vision, olfaction, gustatory and other factors. Yet no sound evidence is available so far. This study concentrated on the olfactory function in foraging and hypothesized that giant pandas are able to discriminate different bamboo species and/or parts singly via olfactory signal from odor. We explored the ability of odor discrimination in bamboo and the material basis by using behavioral experiment and volatile compounds analysis by gas chromatograph-mass spectrometer. The objects of behavioral experiment are 27 healthy adult giant pandas in Yaan Bifengxia Base of China Conservation and Research Center for the Giant Panda, Sichuan. We observed the preference of bamboo in giant pandas by investigation time in two-choice test providing only bamboo odors. Results are as follows. 1. Giant pandas significantly prefer shoots to stems of bamboo, yet no preference to bamboo of different species. Thus, our hypothesis of odor discrimination was partly supported in the aspect of different parts of the bamboo, yet not for the different species of bamboo. The results suggest that giant pandas are able to discriminate shoots from stems of bamboo singly via chemosensory cues, yet the mechanisms of their discrimination of different bamboo species need to be addressed further. 2. After analyzing the volatile compounds of bamboo samples from 16 different species or parts by GC-MS, we totally detected 33 compounds. The amount of compounds in stems was less than 5 and that in leaves varied from 13 to 20. There were 11 compounds detected in shoots including acetic acid and heptanal that was absence in stems and leaves of this experiment. We found high variances in chemical components among different parts of bamboo both in discriminant analysis and principal components analysis. Variances in components were found among different species in leaves as well. Our results show that giant pandas can discriminate shoots from stems of bamboo via chemosensory cues, yet show no significant preference to different species. The high variances in chemical components may reveal the material basis of the discrimination. This result will be helpful for understanding the food preference and management for captive population.