Switzerland's people will vote this week on whether they want to ban factory farming.

Under the Swiss constitution, 'popular initiatives' can be put before the electorate if they have enough support, and be voted upon in a form of direct democracy, much like the UK's single issue 'Brexit' referendum.

Animal rights and animal welfare organisations have submitted one such legislative bid, calling for the 'protection of the dignity of livestock' and a ban on intensive farming to be enshrined in the Swiss constitution.

Supported by Greenpeace, Bio Suisse, the Small Farmers' Association, the Swiss Animal Protection Society, Pro Natura and the Green Party, the initiative defines intensive livestock farming as 'ndustrial livestock farming aimed at making the production of animal products as efficient as possible and systematically undermining animal welfare'.

However, the Swiss government and parliament consider farm animals to be adequately protected under their current legislation – particularly as Switzerland is considered to lead the world in farm animal welfare – and are calling on voters to reject the initiative.

In Switzerland, keeping hens in battery cages was banned in 1996, and there is existing legislation stipulating minimum dimensions of living space for pets, livestock and poultry. The Ordinance on Maximum Stocking Levels in Meat and Egg Production sets a limit on the number of animals from each species, with farms not allowed to keep more than 1500 fattening pigs, 27,000 broiler chickens or 300 calves.

But the initiative’s organisers view these numbers as still too high to ensure the welfare of the animals. They want livestock and poultry to be kept in smaller groups with more space and guaranteed outdoor access.

“This is a fantastic opportunity for the people of Switzerland to lead the way in Europe and start to reform the outdated agricultural system," said Jasmijn de Boo, vice president of ProVeg International. "Factory farming should no longer be tolerated today not only because of the suffering it causes to animals but also because of its huge environmental impact.

“We urge EU lawmakers to look at similar measures restricting factory farming so that Switzerland does not face obstacles to trade and a level-playing field is created for all farmers, both arable and livestock,” she added.