Bai Yun, the female giant panda at the San Diego Zoo, underwent a dental procedure Wednesday to fix a chipped tooth that could have impaired her ability to eat bamboo, her favorite food. 
 
 The 23-year-old panda was given anesthesia so that a veterinary team could repair the chipped tooth, a lower canine. A dental composite was then used to fill the damaged tooth. 
 
 Bai Yun's teeth were then cleaned and a few more X-rays were taken. 
 
 A bad tooth can be hard on any animal. But pandas are particularly vulnerable to damaged or worn down teeth. 
 
 The problem is that bamboo is chewy and not particularly nutritious. To get enough nutrition, giant pandas need to eat a lot of bamboo and they spend a lot of time chewing and breaking it apart. 
 
 Bai Yun has been known to spend up to 12 hours a day dining on bamboo. ||||| Even giant pandas have to see the dentist from time to time. The San Diego Zoo’s panda Bai Yun underwent a dental procedure Wednesday to fix a broken tooth. 
 
 Animal keepers noticed one of the 23-year-old panda’s lower teeth was chipped, so the zoo’s veterinary team anesthetized her, took X-rays and made repairs. 
 
 “The good news is the pulp canal hadn’t been compromised, but it’s very close to breaking into the pulp canal,” said Meg Sutherland-Smith, associate director of veterinary services at the zoo. “What we attempted to do was a restorative procedure to cover up the part of the tooth that was chipped to, hopefully, prevent any further chipping or deterioration.” 
 
 Giant pandas use their teeth to chew and break apart bamboo, so their teeth can get worn or damaged over time. Giant pandas such as Bai Yun, a mother of six, can spend up to 12 hours a day eating bamboo, which is the primary source of their nutrition. 
 
 Giant pandas in the U.S. are on a research loan from China. The San Diego Zoo is one of four in the United States that participate in the program. 
 
 For a hefty fee to China, the zoos get to study the critically endangered species up close and help with breeding. At the same time, the pandas make for highly popular attractions. 
 
 Only around 1,600 pandas are believed to be left in the wild in China, in part because of deforestation and the expansion of farming. The panda has lost much of its forest habitat in the mountainous areas of southwest China to roads and railroads, according to the nonprofit World Wildlife Fund. 
 
 — City News Service ||||| Giant pandas have the 'wrong types' of gut bacteria for efficiently digesting bamboo, scientists suggest. 
 
 Despite spending up to 14 hours per day munching about 12.5 kg (27.5 lbs) of the plants’ stems and leaves, the animals can only digest about 17% of what they consume. 
 
 Scientists in China have shown giant pandas’ gut microbiota – the microscopic plant and animal life naturally found in the intestine – have not seemingly adapted to deal with bamboo. 
 
 This combined scenario may have increased their risk of extinction 
 
 Giant pandas have eaten an almost exclusive bamboo diet for about 2 million years, but they evolved from bears that ate both plants and meat. 
 
 Previous research has suggested the bears’ digestive systems are better suited to a carnivorous diet, leaving researchers intrigued by how the animals actually digest and gain nourishment from bamboo. 
 
 It was thought that pandas' gut microbiota, which aid in the digestion and absorption of nutrients, may have shown a specialisation towards a herbivorous diet. 
 
 However, the results of the new study found the bears' gut microbiota is not made up of plant-degrading bacteria such as Ruminococcaceae and Bacteroides, but other bacteria such as Escherichia and Streptococcus. 
 
 “Unlike other plant-eating animals that have successfully evolved anatomically specialised digestive systems to effectively deconstruct fibrous plant matter, the giant panda still retains a gastrointestinal tract typical of carnivores,” said research team member Dr Zhihe Zhang from the Chengdu Research Base of Giant Panda Breeding, China. 
 
 Furthermore, pandas do not have the genes for producing plant-digesting enzymes. 
 
 “This combined scenario may have increased their risk of extinction,” said Dr Zhang. 
 
 Details of their findings are published in mBio, an online journal published by the American Society for Microbiology. 
 
 To carry out the research, the team examined 121 droppings from 45 captive giant pandas, using a laboratory sequencing method to evaluate gut microbiota. 
 
 The findings, together with previous examinations of nine more captive pandas and seven wild individuals, showed extremely low gut microbiota diversity. 
 
 It also shows an overall composition typical of omnivorous and meat-eating bears and entirely differentiated from other herbivores, with low levels of bacteria that are thought to break down the tough cellulose found in their bamboo diet. 
 
 The gut microbiota of this herbivore, therefore, may not have well adapted to its highly fibrous diet, suggesting a potential link with its poor digestive efficiency. 
 
 The researchers are hoping to carry out further studies to try and understand the role and function of the panda's gut microbiota on their health and nutrition. 
 
 Giant pandas are listed as endangered on the IUCN’s (International Union for Conservation of Nature) Red List of Threatened Species, with fewer than 2,500 adults left in the wild. 
 
 These populations are restricted to the mountains of south-central China. About 300 pandas are thought to live in captivity, mainly in China. 
 
 According to the IUCN there has been a general population decline in giant pandas, but it is hoped this may have begun to reverse due to habitat improvements. However the current status of the iconic bear remains unclear. 
 
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– One of the most reproductively successful pandas in captivity is no longer stuck with a chipped tooth. On Wednesday, the San Diego Zoo's giant female panda Bai Yun underwent a procedure to fix a chipped lower canine tooth that could have seriously cut down her bamboo consumption, the Los Angeles Times reports. A veterinarian team gave the 23-year-old panda anesthesia, then used a dental composite to fill the damaged area before giving Bai Yun's chompers a cleaning. "The good news is the pulp canal hadn't been compromised, but it's very close to breaking into the pulp canal," the vet said, per the Times of San Diego. The procedure will "hopefully, prevent any further chipping or deterioration." That's good news for Bai Yun, who spends up to 12 hours a day munching on bamboo. The effort used to break down the chewy and not-so-nutritious food makes pandas especially prone to damaged teeth, the Times reports.