Ahead of this year's parliamentary elections, the German Greens party has called for an end to factory farming. During the industrial breeding of chickens, young chicks are often treated particularly badly, say critics.
They're known as one-day chicks - baby chickens that never grow older than a day. Thousands of them are killed every day across Germany. The reason: they are male, so they won't lay any eggs, so feeding them up simply isn't economically viable.
When chicks are hatched in industrial hatcheries, workers set to work, sorting the seething fluffy masses into male and female. The hens go onto the right-hand conveyor belt, are packed into boxes and sent to breeding farms. The cocks, meanwhile, end up on the left-hand conveyor belt, where a steel slide sends them to certain death.
"There are chickens for fattening, and laying chickens, which lay a lot of eggs," explains Marius Tünte from German animal protection organization, Deutscher Tierschutzbund. "So the male chicks among the laying breeds don't have any economic value. That's why the decision was made at some point to kill all the male animals."
Over 40 million animals are destroyed in this way every year in Germany - and around 2.5 billion worldwide. It's all part of increased specialization in the industrial farming sector, says Tünte.
Shredded or gassed
The male chicks are either chopped to pieces in a kind of chaffcutter fitted with multiple sharp knives, or gassed using carbon dioxide.
"In both cases, the animals often have to suffer before finally dying," says Tünte. "In the chaffcutter, animals occasionally survive severely injured, and in the videos of the gassing you see clearly that the animals fight for air before they die."
The dead chicks are then ground into animal meal before being burned. Some of the gassed chicks end up as feed for birds of prey in zoos - but, according to Deutscher Tierschutzbund, that only amounts to a few percent.
It is only after the chicks have been sorted into male and female that the companies decide whether they are to be reared in a cage, or if they are to become "organic hens." Organic farmers buy their laying hens at the breeding farms too - so organic farms cannot opt out of the system.
"At the moment, there are no alternatives to the market," Gerald Wehde, spokesman for the farming association Bioland, told DW. "All we can do is try to alleviate the situation a little."
On top of this, farmers generally slaughter the laying hens as soon as they are a year old and begin to molt. Bioland advises its members to let their hens live a little longer, because they still lay eggs after molting, if not quite as many.
If more hens were allowed to live into their second laying period, then farmers wouldn't have to buy as many laying hens, explains Wehde. "Then we could at least reduce the number of murdered chicks, if not actually stop it."
Breaking the law?
According to Paragraph 1 of Germany's Animal Protection Law, animals may only be killed for a useful reason. Animal protectionists, and indeed some lawyers, have their doubts about whether such a reason can be said to exist in the case of one-day chicks.
And yet the practice is allowed to continue. An EU directive even regulates how the shredding and gassing of chicks is to be carried out - the chaffcutter is not allowed to be overloaded and the chicks are not allowed to be older than 72 hours old when killed.
The German Ministry for Food, Agriculture, and Consumer Protection said, in reply to DW's request for a statement, that "the killing of male one-day chicks should be the last resort after all other possibilities for the use of the animals have been exhausted." But, according to industry, there is no other use for the animals, except for the unprofitable fattening.
Solutions in sight?
Most parties have now grasped that the killing of billions of chicks worldwide each year is neither practical nor morally defendable, even the breeding firms themselves. They incubate vast quantities of eggs every year for no useful reason, and have to dispose of the dead chicks afterwards.
"No one, including the industry, actually wants to have to kill healthy male one-day chicks," says Maria-Elisabeth Krautwald-Junghanns, veterinarian and researcher at Leipzig University. She researches ways to potentially determine the sex of a chicken embryo even before it is hatched. She's hoping her research will mean that, in the future, only female embryos will be incubated.
For chicken breeders and animal protectionists, the best solution would be to develop chicken breeds that can do both - the females lay eggs, while the males can be fattened. This was common before 1950. Sorting chicks on the basis of sex has become normal though now because high performance breeding is more efficient.
In other countries, such as Italy or Switzerland, the concept of the dual-purpose chicken already exists as a niche product. In Germany it is about to be introduced to the market.
Until then, consumers who want to boycott the killing of chicks have only one option, says Tünte, namely "to abstain or eat fewer egg-based products."