Information sourced from UK Government, BBC.
Male chicks in the egg industry are killed shortly after birth usually in a gas chamber or less frequently by blending alive. Male egg laying chicks are not raised for their flesh because they are a different breed making doing so unprofitable.
Under UK law surplus chicks may be killed for any reason either by gas chamber, blending alive, or snapping the neck. It is not a requirement that they are male, although these are most often the one that are culled.
Male chicks being blended alive