In commercial hatcheries, eggs are incubated in large setters for 18-19 days (layers/broilers) before being transferred to hatchers for the final 3 days. Chicks hatch over a period of up to 36 hours; those hatching early may wait without food or water for extended periods before being processed. Research indicates that delays in accessing feed and water cause welfare compromise and impair gut development.
In the layer industry, male chicks cannot lay eggs and are not economically viable to rear as meat. Approximately 30 million male chicks are culled in the UK annually. The primary culling methods are maceration (high-speed shredding) and gassing (CO2 or mixed gases). Both are considered humane when executed correctly. The practice is subject to growing ethical scrutiny and consumer pressure.
In-ovo sexing technologies determine the sex of embryos before hatching, allowing male eggs to be diverted before a chick develops. Methods include hormonal analysis of allantoic fluid, hyperspectral imaging, and PCR-based genetic sex testing. Germany banned male chick culling from 2022, accelerating in-ovo adoption. In-ovo sexing eliminates the welfare cost of hatching and then immediately killing male chicks, though the welfare status of early embryos remains debated.
Dual-purpose breeds produce hens suitable for egg laying and cockerels suitable for meat production, eliminating the male-kill problem without in-ovo technology. Welfare trade-offs include slower growth in meat-type birds and lower egg production in laying hens. Several welfare certification schemes now offer dual-purpose breed options as a premium choice.
Day-old chicks are transported from hatcheries to rearing facilities, often over long distances. They rely on yolk sac reserves during transport. Maximum permitted transport time in the UK and EU is 24 hours for chicks. Temperature control during transit is critical; chilling and overheating both cause welfare compromise and mortality.
Chick placement welfare depends on: suitable temperature (33-35°C for day-olds), immediate access to feed and water, appropriate litter depth, and sufficient space. Early-life thermal comfort is a strong predictor of subsequent welfare and performance. Good quality brooding management is foundational to the welfare of the entire crop.