Queen rocker and animal rights activist Brian May has condemned officials at a Danish zoo over the controversial killing of a giraffe and called for a boycott.

The healthy young animal, named Marius, was deemed unfit for breeding, so officials at Copenhagen Zoo decided to put him down.

The giraffe was killed with a bolt gun and dissected in front of onlookers before being fed to the zoo's lions, prompting an outcry from animal lovers across the world.

May has condemned zoo officials for carrying out the shocking act in the name of science and called for a boycott of the institution.

In a post on his official blog, May writes, "An appalling, senseless act of cruelty. Along with most of the rest of the world, we're disgusted to see that this zoo ignored the many offers to re-home this poor animal, and mercilessly, as if they were proud of it, for all to see, ended its life... I believe the only way decent people can make their feelings known on this is to absolutely boycott the Copenhagen Zoo. I believe that by this stupid act, the guardians of this zoo have hastened its demise as an institution. For me, it would be a worthy and just outcome of this tragedy."