Is it cruel to keep a pet fox... on a vegan diet?

An animal rights activist has kicked off a fierce debate about whether it's healthy and humane to keep a pet fox - and feed it a vegan diet.

The controversy started when Sonia Sae - a self-described "anti-speciesist" - revealed on social media that she is raising Jumanji, her pet male fennec fox, on a purely plant-based diet.

The accompanying pictures of Jumanji have prompted heated conversations across a variety of social media platforms, with even some other vegans criticising Sae for imposing her ideas on the animal.

According to National Geographic, fennec foxes are "omnivores" and "opportunistic eaters" in the wild, who typically "forage for plants but also eat rodents, eggs, reptiles, and insects."

Sae - a vegan campaigner from Barcelona - has defended her actions online and posted videos on her YouTube channel making the case for vegan pet foods. But this has not satiated her critics on social media.

On Twitter @IceDarkEmerald_ claimed the animal looked "extremely malnourished", while YouTuber Foshee took his opposition one step further, recording two YouTube videos encouraging his viewers to #FightForTheFox and report Sae to the campaigning organisation People for the Ethical Treatment of Animals (PETA).

However, a few animal rights activists did come to Sae's defence. On Facebook, Joana Leal countered claims that the fox's hair loss was due to his diet. She wrote: "Foxes shed just like cats. And research shows they do thrive on a vegan diet supplemented with taurine," a key nutritional supplement. Katie Marie added "her fox looks fine, and the only ones I see attacking her are you carnists" - in other words, meat eaters.

Sae herself reacted to criticism of her pet welfare on her Facebook page, insisting that the fox is not suffering because of its vegan diet.

"Jumanji has a skin allergy due to plant pollen," she wrote. "He had it before going plant based. This allergy manifests itself during plant pollinating seasons (spring/summer) and it disappears when it finishes (autumn/winter). In all pictures he weights around the same... which is a normal weight for a fennec fox".

Damian Eadie, who runs a UK-based business selling vegan pet food, told BBC Trending it was possible for pets to do without meat provided they received nutrients from an alternative source.

"Most people have an apoplectic fit when they hear about pets being given vegan food," he said. "A reasonable thing to say to Sonia would be - how are you sure this is safe for the fox? Does she know the nutritional requirements of the fox and can she formulate a suitable diet?... Any animal can be fed a vegan diet if you can source the nutrients appropriately.

"It doesn't make sense to talk about what's natural if the fox is living in a human household, where the options are very different. In the wild they would get the protein from prey, but in a domestic household they could get it from farmed animals or plant protein."

However, for some animal rights campaigners, their concerns about Jumanji's welfare stretch further than its diet - to the fact that the fox is being kept as a domestic pet at all.

"Fennec foxes are sensitive, vulnerable nocturnal animals who are naturally frightened of humans and should never be kept as companion animals," says Dr Heather Rally, a supervising veterinarian for the PETA Foundation.

"PETA is urging Ms Sae to send this displaced fox to a sanctuary that can meet his complex needs and to visit her local animal shelter, where a lovable dog or cat has been waiting for her," Rally says.

BBC Trending attempted to contact Sonia Sae for comment.

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