No glasses for chickens – and other odd Swiss animal laws

A scene from Walt Disney's animated film Chicken Little. Copyright Walt Disney Co. / Courtesy Everett / Everett Collection

Switzerland stands out for its strict animal welfare laws that seem to go further than other countries. But is this really the case? Take, for example, the illegality of glasses and contact lenses for chickens.

Some time ago, the British BBC programme Quite Interesting posted a curious anecdote about the Switzerland on its Facebook page: “In Switzerland it’s illegal to force domestic poultry to wear glasses or contact lenses”.

Contact lenses and glasses for chickens prohibited by law? When did that ever happen? Is it possible that the BBC’s editorial staff had made a mistake.

No, they didn’t. Article 20 of the Animal Protection Ordinance (OPAn) lists prohibited practices on domestic birds. These include: ‘The use of glasses and contact lenses as well as the application of devices that prevent the beak from closing.’

The needs for such a regulation is linked to a practice that is still possible in various countries, even if it is no longer very widespread.

Cannibalistic chickens

According to Sibel Konyo from the Zurich-based animal rights foundation Tier Im Recht (TIR), the use of glasses and contact lenses on poultry is an attempt to adapt birds to housing conditions that are not “animal-friendly”.

When roosters and hens are confined to a limited space without sufficient distractions, they can injure each other and develop cannibalistic tendencies. To prevent this, one practice still used around the world is beak trimming. Another is the use of “glasses”. These are not designed to improve the chicken’s vision, but to reduce it, with red lenses or even blinders.

The chickens at a farm of the local armed police force in east China’s Jiangsu province were forced to put on special glasses to prevent them from fighting and cannibalism. Fei Bojun – Imaginechina

The idea behind the coloured lenses, first produced in the United States at the beginning of the 20^th century, was to prevent poultry from distinguishing the colour of blood, which was said to make hens and roosters more aggressive.

A 1947 newsreel on glasses for chickens from the US manufacturer National Band and Tag Company:

However, fitting these devices – with a clamp or a needle that pierces the beak – is painful for the animals, that also risk bumping into objects they can no longer see, explains Konyo.

Contact lenses serve the same purpose. In the 1980s, in the United States, the company Animalens patentedExternal link and promoted the use of red contact lenses for poultry.

Animalens extolled the supposed benefits of the invention: increased egg production, reduced feed consumption and lower mortality rates. However, subsequent studies showed that the only notable difference between a laying hen using contact lenses and one that did not was the incidence of eye infections.

Eyeglasses for chickens patent, 1903. Artwork of a device designed by Andrew Jackson Jr. to protect the eyes of chickens from aggressive pecking by other chickens. Us Patent And Trademark Office / Science Photo Library

A lexical curiosity

It is therefore not surprising that Switzerland introduced this ban in a major amendment to the Animal Protection Ordinance in force since 2008.

It should be noted, however, that similar rules already existed in other countries, including the United Kingdom.

The BBC should not be blamed for describing the rule as a Swiss peculiarity. British lawExternal link uses more technical terms in its list of prohibited operations: ‘fitting any appliance which has the object or effect of limiting vision to a bird by a method involving the penetration or other mutilation of the nasal septum’.

The term ‘chicken glasses’ is therefore a curiosity that derives from the lexical field rather than the legal field, and is probably due to the simpler and more direct language used in Switzerland (see box).

Swiss legal texts are clearer because they are multilingual

The authors of a recent study on the differences between Italian spoken in Switzerland and Italian spoken in Italy highlighted the greater clarity of Swiss legal texts.

“The official texts of the Swiss Confederation in Italian are almost always translations of German or French texts. Surprisingly, this is not an obstacle, but rather an opportunity for their communicative quality,” emphasised linguistics professor Angela Rossi of the University of Basel, who conducted the study, in September 2024.

The federal government’s translators act as careful ‘testers’, checking whether the source text is coherent and clear, and taking corrective action if necessary. Official legislative texts are translated as the originals are produced, discussed and, if necessary, reworded during the various parliamentary sessions, Rossi explained to news agency Keystone-SDA.

Animal dignity

Although the ban on glasses and contact lenses for chickens is not unique to Switzerland, this does not mean that Switzerland does not stand out internationally for its relatively strict animal welfare legislation.

The best-known example is that of guinea pigs. In Switzerland, it is illegal to own just one. This is because they are social animals which, like rabbits, ferrets and parrots, suffer if they do not have the company of their own kind.

This rule also came into force with the revision of the Animal Protection Ordinance in 2008, which was in turn drafted in the wake of the major amendment to the relevant federal law in 2005.

A view of two guinea pigs in a cage. Ole Berg-Rusten / Ntb

This revision is considered a major success for the Swiss Central Association for Animal Protection, many of whose demands were incorporated into the text, explained Heinz Lienhard, then director of the association, in this interview with swissinfo.ch.

The most important and uniquely Swiss aspect, says Sibel Konyo, is the introduction, with the 2005 revision, of the concept of ‘animal dignity’ (Art. 3 lit.a of the LPAn). “In terms of animal protection law, safeguarding animal dignity represents a milestone and a step into a biocentric dimension, granting animals a legally protected value regardless of their capacity for perception,” explains the expert, who believes, however, that there is much room for improvement.

“For example, due to the lack of a specific criminal provision, such as that contained in the German Animal Welfare Act, the killing of an animal without a valid reason remains unpunished under Swiss law.”

Not more than 300 hamsters per year

The regulatory machine has not stopped since 2008. Noteworthy for its Swiss precision is one of the latest amendments to the Animal Protection Ordinance introduced in February 2025. It establishes the number of animals that can be sold to third parties annually, beyond which farm managers are required to apply for cantonal authorisation.

‘Three hundred mice, rats, hamsters or gerbils’, reads point 4, for example. Its meticulousness pales in comparison to point 7 that restricts acquisition of exotic birds to “the offspring of no more than 25 pairs of birds no larger than a cockatiel, no more than 10 pairs of birds larger than cockatiels, or more than five pairs of macaws or cockatoos”.

Legislators therefore continue to work tirelessly for animals, even if, at times, they are unable to maintain their composure.

“We have become a zoo by talking so much about animals,” said then-Senator Géraldine Savary ironically in 2015 during a session of the Senate in which the importation of shark fins was discussed. When, shortly afterwards, she had to ask the plenary to approve a motion to combat Scrapie disease affecting sheep, she was unable to suppress a giggle.

Edited by Daniele Mariani. Adapated from Italian by DeepL/ac