研究揭示为什么大熊猫爱吃竹子
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. Researchers performed a large-scale metagenome sequencing study of the gut microbiota of giant pandas, which feed almost exclusively on bamboo. They found that their gut microbiota does not significantly contribute to the degradation of cellulose and lignin, which are abundant in bamboo. The finding suggests that the animals do not depend on cellulose or lignin to obtain energy. Instead, they rely on starch and hemicelluloses in the plant for energy, researchers said. 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. 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. "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." |