'Everyone' wants to end “chick culling.” So what’s the holdup? Every year, up to 7 billion day-old male chicks are tossed into shredding machines, gassed, or suffocated in plastic bags—a process known as “chick culling.” This grim ritual is underpinned by both biology and economics: Male chicks don’t lay eggs, and they fatten up too slowly to be sold as meat. Across the globe, culling has become the default strategy for the egg industry to eliminate unwanted hatchlings. “It is horrible. You see these puffy, newly hatched chicks on a conveyor belt,” headed toward a large blade that slices them “into a gazillion pieces,” says Leah Garcés, president of Mercy for Animals, an animal-rights advocacy group in the United States. In recent years, local and international animal-rights groups, particularly in France, Germany, and the U.S., have been ramping up pressure on governments and the egg industry to commit to ending the practice—particularly given technological innovations that...