The female tiger is shown looking half starved, in a room almost devoid of any stimulation.
The Tianjin zoo in China has been bombarded with hate mail since the video footage emerged. They are the same zoo that made headlines for teaching elephants martial arts.
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'Whoever has a clue how to help, please take action to improve the tiger's living condition. I am asking for the people concerned to investigate it and to treat animals better,' a Weibo user commented on the post.
But zookeeper Wei K'ung has responded to the allegations of cruelty by saying that the tiger is sick, and that's why she looks so underweight.
'She had a digestive disorder since she was a cub but it worsened as she aged. She is now 13, that makes her an OAP in tiger terms, and the medicine she has been given no longer works so well. That is the reason she seems so thin,' they said.
The zoo also denied that the female tiger is pain, and that they would consider putting her to sleep if she was suffering.