研究揭示爲什麼大熊貓愛吃竹子大綱

A study has shed new light on how bamboo, a highly fibrous plant, provides energy for giant pandas, which have a digestive tract similar to carnivores.

一項研究揭示了竹子這種高度纖維狀植物，是如何爲大熊貓這種消化道與食肉動物相似的動物提供能量的。

Researchers performed a large-scale metagenome sequencing study of the gut microbiota of giant pandas, which feed almost exclusively on bamboo.

研究人員對大熊貓腸道微生物羣進行了大規模的宏基因組研究，這些大熊貓幾乎完全以竹子爲食。

They found that their gut microbiota does not significantly contribute to the degradation of cellulose and lignin, which are abundant in bamboo.

他們發現，它們的腸道微生物羣對富含在竹子內的纖維素和木質素的降解沒有顯著的作用。

The finding suggests that the animals do not depend on cellulose or lignin to obtain energy.

這一發現表明，這種動物並不依賴纖維素或木質素來獲得能量。

Instead, they rely on starch and hemicelluloses in the plant for energy, researchers said.

研究人員稱，相反，他們依靠植物中的澱粉和半纖維素來獲取能量。

Giant pandas have a higher capability of digesting starch than strict carnivores. They develop increasing abilities to digest starch following the dietary transition from breast milk to bamboo, according to the study.

大熊貓比嚴格意義上的食肉動物有着更強大的消化澱粉的能力。根據這項研究，大熊貓完成從母乳到竹子的飲食方式轉變後，便逐步發展其消化澱粉的能力。

The animals have much higher digestibility for hemicellulose than cellulose, and they prefer bamboo shoots, tender leaves and first-year bamboo, with an abundance of hemicelluloses.

這種動物對半纖維素的消化率遠高於纖維素，它們更喜歡竹筍、嫩葉和一年生竹這些半纖維素含量豐富的植物。

"Giant pandas love bamboo partly because it is everywhere in their habitats, and they have few competitors for the food," said Zhang Wenping, who is the first author of the research paper. "In addition, bamboo has high levels of starch among all woody plants."

該研究報告的第一作者張文平表示：“大熊貓喜歡竹子，部分原因是竹子在它們的棲息地到處都是，而且它們幾乎沒有吃這種食物的競爭對手。除此之外，在所有木本植物中，竹子的澱粉含量也相對較高。”