There was no hiding the devastation on last night's episode of Channel 4's weekly documentary about the animals of Chester Zoo, which saw the loss of one of its beloved baby elephants.
After previous weeks that have featured newborn giraffes, inseparable penguins and work-shy aardvarks, the latest episode of the six-part miniseries Secret Life of the Zoo saw the sadness that ensued at the zoo when young Asian elephant Bala Hi Way passed away in September.
Two-year-old Bala tested positive for elephant endotheliotropic herpesvirus (EEHV), a fast-moving virus which affects both wild and captive elephants between the ages of two and five years old, leaving staff at the zoo devastated.
Another member of the Hi Way family, Hari, also died of EEHV a month later.
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Viewers took to Twitter to express their sadness at the deaths of Bala, with one person saying she was 'heartbroken' to watch it. Another said they cried all the way through the programme.
But on a more positive note, audiences were also shown the birth of baby elephant Nandita, born only a month before Bala's sad death - and she is currently a popular member of the zoo's elephant family.
After Hari's death, Mike Jordan, Chester Zoo's collections director, described EEHV as a 'terrible virus' which affects young elephants typically around weaning age.
"In many elephants it can lie dormant and undetectable and never develops into the disease but others are susceptible to it – currently no one knows why some elephants get it and others don’t."
He explained: "For many years we’ve funded vital research into EEHV but researchers have yet to be able to culture the virus which is necessary to create a vaccine and determine what drugs are most effective. At present, drug treatment is effective in only around one-third of cases and survival rates overall are around 20%.
"We have a responsibility to do everything we can to understand this disease in order to have a chance of eradicating it, both in zoos and, crucially, in the wild. Asian elephants are endangered and it’s hoped that the work being done in captivity will hold the key to unlocking the information researchers need to make a positive breakthrough," added Mr Jordan.
Watch a video of Nandita playing at Chester Zoo
