Officials at Copenhagen Zoo in Denmark say they received death threats after the zoo killed a two-year-old giraffe and fed its remains to lions.
Zoo spokesman Tobias Stenbaek Bro said that he and the zoo's scientific director, Bengt Holst, received several threats over the telephone and in emails. They quoted one email as saying: "The children of the staff of Copenhagen Zoo should all be killed or should get cancer."
The giraffe, Marius, was killed on Sunday using a bolt pistol, then skinned and fed to lions in front of visitors, including several children who looked on in shock.
The killing triggered a wave of revulsion and protests sparking a debate about zoo conditions.
The zoo said it killed Marius to prevent inbreeding, and it defended the public feeding as a display of scientific knowledge about animals.
But in Denmark, an overwhelming majority of social media users felt the global outcry was a sign of hypocrisy and political correctness.
A leading expert on the ethics of the treatment of animals decried the "Disneyfication" of zoo creatures.
A journalist for the 'Politiken' newspaper, Kristian Madsen, wrote on Twitter: "The whole world has gone crazy. What do they imagine the lions eat on days without a treat such as Marius? Brussel sprouts?"
Dorte Dejbjerg Arens, a project co-ordinator, said: "I'm still livid over Marius. How can people get so hysterical over a giraffe while cancer, the war in Syria and the (anti-immigrant) Danish People's Party still exist."
The giraffe was put down with a bolt gun and then chopped up and fed to lion as visitors, including children, looked on. The zoo said it had no choice other than to prevent the animal attaining adulthood since under European Association of Zoos and Aquaria rules, inbreeding between giraffes is to be avoided.
One expert said the muted public reaction in Denmark could partly be explained by cultural factors.
"Denmark was urbanised relatively late, which is why the general opinion here is that it's okay to keep and kill animals as long as you treat them well," said Peter Sandoee, a professor of bioethics at the University of Copenhagen.
"Animal rights activists in Denmark aren't nearly as strong as they are in Britain or the US."
Arguing that "one of the most fundamental aspects of animals' conditions in the wild is that only a fraction of them survive", Mr Sandoee lashed out at what he called the "Disneyfication" of zoos.
"You take this very romantic image of animals as people with fur or feathers. Animals are viewed as a type of citizen, with the implication that they should be treated on par with fellow human beings."
A zoo's primary job should be to preserve different species and contribute to learning about how animals live in the wild, he said.
In the past, the Copenhagen zoo has allowed tigers and lions to reproduce, killing the "surplus offspring" rather than castrating the animals or giving them contraceptives, he added. "I think Copenhagen Zoo takes a progressive stance here because in doing so they (mimic) the animals' natural life," he said.