Pandas eat anything from 26 to 84 pounds of bamboo every day, depending on which part of the plant they eat.
Researchers have found out how pandas can gain weight while solely eating bamboo.
It turns out that the bacteria in the animals’ guts changes as the season progresses and more nutritious bamboo shoots become available.
According to a research by the Chinese Academy of Sciences’ Institute of Zoology, this helps bears store more fat which may compensate for the lack of nutrition in seasons when there are only bamboo leaves to chew on.
“This is the first time we demonstrated a causal association between a panda’s gut microbiota and its phenotype,” said Guangping Huang, one of the study’s authors.
“We’ve known for a long time that these pandas have a different gut microbiome during shoot-eating season, and it’s pretty evident that they’re chubbier at this time of year.”
According to the World Wildlife Fund, a newborn panda is nearly the size of a stick of butter, although females may reach 90 kg and males can reach 136 kg.
Bamboo shoots the animals eat protein-rich newly emerged bamboo shoots in late spring and early summer, a change from the normal fibrous bamboo available.
The researchers discovered that during shoot-eating season, wild pandas in central China’s Qinling Mountains have a much greater amount of a bacteria called clostridium butyricum in their gut.
They did a faecal transplant of panda faecel gathered in the wild to germ-free mice to examine the effect of this shift on a panda’s metabolism.
The mice were subsequently provided a bamboo-based diet comparable to that of pandas for three weeks.
Mice transplanted with panda faeces obtained during the shoot-eating season acquired much more weight and fat than mice transplanted with faeces collected during the leaf-eating season.
The bacteria, according to the researchers, may cause the bears to store extra fat.
Butyrate, its metabolic product, is sold to humans as a probiotic supplement, although its safety is a point of contention.