New research shows giant pandas' gut bacteria can't efficiently digest bamboo after all.
The recent study shows these animals' gut microbiota closely resembles what would be seen in a carnivore, the American Society for Microbiology reported. The giant panda's gut bacteria proved to contai Escherichia/Shigella and Streptococcus.
Unlike other plant-eating animals that have successfully evolved, anatomically specialized digestive systems to efficiently deconstruct fibrous plant matter, the giant panda still retains a gastrointestinal tract typical of carnivores," said lead study author Zhihe Zhang, director of the Chengdu Research Base of Giant Panda Breeding, China. "The animals also do not have the genes for plant-digesting enzymes in their own genome. This combined scenario may have increased their risk for extinction."
Giant pandas evolved from meat-eating bears, and new research suggests their gut bacteria have not successfully evolved to fit their new diet. These animals now spend up to 14 hours a day earing as much as 27.5 pounds of bamboo leaves and stems, even though they can only digest about 17 percent. Their feces contains a large amount of these undigested bamboo products.
The researchers used a technique called 16S rRNA sequencing to analyze 121 fecal samples from 45 giant pandas. They found that despite their diet, the pandas did not have any plant-degrading bacteria in their stomachs.
"This result is unexpected and quite interesting, because it implies the giant panda's gut microbiota may not have well adapted to its unique diet, and places pandas at an evolutionary dilemma," said study coauthor Xiaoyan Pang, an associate professor in the School of Life Sciences and Biotechnology at Shanghai Jiao Tong University.
The findings were published in a recent edition of the journal mBio®.