Castration anxiety can also refer to being castrated symbolically. When the Chinese overthrew Mongol rule, many Mongol captives were castrated and turned into eunuchs. Male hogs are usually castrated a month before slaughter. For centuries, pigs have been castrated to prevent boar taint. His men rescued two boys who had just been castrated by their captors. Male slaves were castrated in order to serve as harem guards. Many would be castrated and sold as eunuchs as well. Both are castrated and keep their removed penises in containers around their necks. Youth are symbolically castrated, or feminized, but also blessed with masculine fruitfulness. The Arab slave trade typically dealt in the sale of castrated male slaves. Most of the male victims were castrated. A bull is an intact (i.e., not castrated) adult male of the species "Bos taurus". Many were castrated, or had their beards scalped or their tongues cut out. They regularly ride on zari (castrated males). Castrated males are called "wethers".