叶食性灵长类食物选择受食物营养及单宁等次生代谢产物影响,为了探讨单宁对黑白仰鼻猴食物选择的影响,通过磷钼酸-钨酸钠(F-D)比色法测定了拉沙山黑白仰鼻猴群(Rhinopithecus bieti)2010年4月-2012年3月间的取食植物(192种)和非取食植物(188种)单宁含量。结果表明,黑白仰鼻猴群全年食用植物中单宁含量低于非食用植物;春季食用植物中单宁含量高于其他季节,而其他季节无差异;不同取食部位单宁由高到低依次为芽、花、叶、果和地衣;不同季节,不同取食部位单宁有差异,春季芽的单宁含量最高,夏秋季果实中单宁含量最高,冬季叶单宁含量最高;不同月份,食物单宁也不同,3月份食用植物中单宁最高(8.36%±6.22%),2月份最低(1.28%±1.19%)。因此,黑白仰鼻猴根据环境食物种类和供给时空特征,可能采取了从高蛋白纤维比/高单宁到低蛋白纤维比/低单宁连续谱觅食策略。
Food selection by folivorous primates is thought to relate to nutrients and plant secondary metabolites. In order to study the condensed tannin of the food plants and its potential influence on food selection of Rhinopithecus bieti, we collect- ed samples of foraging foods (FF) species ( n = 192) and non-foraging foods (NFF) species ( n = 188 ) of Rhinopithecus bieti at Mt. Lasha, Yunnan b~tween April 2010 to March 2012. We measured the condensed tannins (CT) from these samples using the Folin-Denis method. The results showed that the CT contents in monkey' s food were lower than in NFF. The CT content of FF in spring was higher than other seasons. The CT content of FF did not vary significantly in summer, autumn and winter. Among all the FF items, the condensed tannins levels of monkey' s foods were ranked as : buds 〉 flow- ers 〉 leaves 〉 fruits 〉 lichens. The CT contents in lichen were the lowest all the FF. The CT varied among the different plant parts within a species in different seasons. Buds had the largest average CT in spring. Fruits had the largest average CT in summer and autumn. The CT of leaves was higher than lichen in winter. Monthly average CT of all food species did vary across months. It had the largest average CT (8.36% ±6. 22% ) in March and the lowest average CT ( 1.28%±1.19% ) in February. Therefore, according to the food species and the supply of temporal-spatial characteristics, the Rhinopithecus bieti may adaopt from high protein fiber ratios/high tannin to low protein fiber ratios/low tannin continuous spectrum foraging strategies.