Traditionally, dual-purpose poultry breeds were raised on small farms. The hens were used as layers until they became less productive and were then slaughtered as stewing hens. Other than a rooster or two, males were slaughtered around the time they reached sexual maturity. While hens of dual-purpose breeds can be good layers, the male birds don’t put on enough flesh, particularly breast meat, to satisfy today’s mainstream consumers. Consequently, meat breeds are used for broiler production and laying breeds for eggs on all large operations and many small farms as well.
In commercial egg production, the common practice is to incubate eggs until they hatch. Then, trained personnel called “chick sexers” look at the vents of chicks to determine their sex. This process can be quite accurate after a few years of training. The male chicks are slaughtered when they are a day old.
A German company has developed an alternative approach, which they hope will satisfy vegetarian consumers and people interested in animal welfare.
A laser is used to burn a tiny hole into the shell of a freshly laid egg. A small amount of fluid is removed and tested for the presence of the hormone estrone sulphate. If the female hormone is present, the egg is incubated; no repair is needed as the egg will repair itself. Eggs lacking the hormone (i.e., eggs that would develop into male chicks) are processed into animal feed. The result: no chicks are killed.
Source: German Federal Ministry of Food and Agriculture (BMEL) Press Release. Breakthrough: Stopping chick culling together! November 8, 2018.