黑白仰鼻猴常年采食竹类叶片，竹子是其重要的食物资源之一。本文通过对拉沙山黑白仰鼻猴生境中空心箭竹和马斯箭竹竹叶化学成分进行分析，探讨其采食原由。2011年3月至2012年2月，共采集了21份竹子样品，分析其粗蛋白、粗脂肪、总糖、粗纤维、灰分、钙和总磷等化学成分。结果表明：两种竹叶的选择主要受高钙、高能量和低Ca/P的影响。尽管空心箭竹与马斯箭竹的化学成分无差异，但是影响黑白仰鼻猴食物选择的主要因素有所不同，这可能与竹子化学成分的季节性变化有关。结合前人对该猴群非竹类食物的研究结果，黑白仰鼻猴采取了在满足蛋白质、脂肪等常量营养物质需求基础上优先保证磷、钙和能量摄入的觅食策略。竹类等猴群重要食资源应该受到重点保护，同时也是未来食物资源恢复的首选物种。

Bamboo is one of the main foods of black-and-white snub-nosed monkey (Rhinopithecus bieti). This study is designed to reveal principal chemical components of two bamboo leaves (Fargesia edulis and Fargesia dura), which influence their choice. We collected twenty-one samples of bamboos used by Rhinopithecus bieti at Mt. Lasha, Yunnan from March 2011 to February in 2012. The chemical composition (crude protein, ether extract, total sugar, crude fiber, ash, calcium and total phosphorus) of bamboo were determined from these samples. The results showed that choice of bamboo was mainly affected by higher percentage of calcium and gross energy, and lower ratio of calcium to phosphorus. Thus, the bamboo provides mineral elements required for the survival and reproduction of the monkeys, and is also an important food source of energy. Although there are no differences in the chemical compositions of the two kinds of bamboos, the main factors affecting their choice is different. This may be related to seasonal changes in their chemical compositions. Based on this and previous studies, Rhinopithecus biet prioritizes intake of phosphorus, calcium, and gross energy if macronutrients requirements for protein, ether extract, and others can be satisfied. Main food resources such as bamboo should be protected in the monkey's native habitat since it may be the preferred species of food resource recovery in its destroyed habitats in future.