コラム・連載 質疑応答コーナー ボノボ チンパンジー「アイ」 頭蓋骨画像データベース 霊長類学文献データベース サル飼育・使用指針v3 Study material catalogue/database 野生霊長類研究ガイドライン 霊長類ゲノムデータベース 写真アーカイヴ ビデオアーカイヴ
Factors Affecting Leaf Selection by Foregut-fermenting Proboscis Monkeys: New Insight from in vitro Digestibility and Toughness of Leaves
松田一希・Marcus Clauss・Augustine Tuuga・John Sugau・半谷吾郎・湯本貴和・Henry Bernard・Jürgen Hummel
Free-living animals must make dietary choices in terms of chemical and physical properties, depending on their digestive physiology and availability of food resources. Here we comprehensively evaluated the dietary choices of proboscis monkeys (Nasalis larvatus) consuming young leaves. We analysed the data for leaf toughness and digestibility measured by an in vitro gas production method, in addition to previously reported data on nutrient composition. Leaf toughness, in general, negatively correlated with the crude protein content, one of the most important nutritional factors affecting food selection by leaf-eating primates. This result suggests that leaf toughness assessed by oral sensation might be a proximate cue for its protein content. We confirmed the importance of the leaf chemical properties in terms of preference shown by N. larvatus; leaves with high protein content and low neutral detergent fibre levels were preferred to those of the common plant species. We also found that these preferred leaves were less tough and more digestible than the alternatives. Our in vitro results also suggested that N. larvatus were little affected by secondary plant compounds. However, the spatial distribution pattern of plant species was the strongest factor explaining the selection of the preferred leaf species.
2017/03/01 Primate Research Institute