A Zurich zoo is coming under fire after it was revealed that the meat in its restaurant's schnitzel comes from animals slaughtered from its own collection.

The Langenberg Wildnispark, just south of Zurich, confirmed that it serves venison and boar meat that is sourced from the very animals that visitors come to see.

The revelation about the meat’s origins has since sparked an outcry from visitors to the park, as well as questions surrounding the ethics of the move.

A diner in the restaurant, who noticed how the meat was sourced on the menu, is quoted in the Swiss paper Der Landbote as having said, “Is this a belated April Fools' joke?”

Langenberg’s spokesman, Martin Kilchenmann, confirmed that park visitors can dine on deer and boar from the zoo, complimenting the park’s ecological decision.

He explained that more than 100 animals are born in the park every year, but that not all of them can be housed in the space. If room for the deer and boar cannot be found in other zoos, park officials make the decision to cull them – and "recycle" the meat in the restaurant.

Der Landbote reports that in 2012, 49 deer and 10 wild boars were served as schnitzel in the restaurant, after attempts to find the creatures a new home failed.

But the move has drawn criticism from local animal welfare organisations.

Ruth Widmer, the president of the local animal protection association, described the news as shocking, saying: “I didn’t think such a thing could happen.”

Widmer believes that the park should take greater care in controlling the mating habits of its animals, so that an unsupportable population can be controlled.

But according to Kilchenmann, the zoo’s move has not been hard for visitors to swallow.

“The majority of our guests show goodwill and support our approach,” he said.

(H/T: The Local)