In Russia, a Siberian tiger named Amur and a goat called Timur formed an unlikely bond last November.
The pair began a friendship when Timur was placed in the tiger's habitat as part of its twice weekly live animal feedings.
The pair formed a remarkable bond and were often seen following each other around the enclosure and even napping together.
But alas, the pair have now had a falling out and Timur has been removed from Amur's enclosure.
Mezentsev said Timur had a history of being a bully and it appeared Amur finally tired of being pushed around.
"Timur pushed Amur down the slope, poked him with his horns and legs, and finally stepped on Amur while he was sleeping," Mezentsev said.
"Amur woke up, grabbed Timur with his teeth, shook him like a kitten, and threw him away. Then he lay down to rest again."
Timur was removed from the enclosure and is receiving medical treatment.
Mezentsev said he does not believe Amur ever wanted to kill Timur.
"If the tiger wanted to kill the goat, he would have already done it. Amur's patience in this situation amazes me. He had been looking indulgently for so long on brazen Timur," he told the Siberian Times.
But he said it was "too early" to say if the tiger and goat could be reunited. "At the moment the goat needs to recover and relax."
Get well soon Timur!
We hope the friendship can recover.