Following on from my blog post about the "murder" at the Nanakuli animal shelter, here is an account from Wikipedia of the mass murder process at a slaughterhouse (this is not for the faint of heart):
The slaughterhouse process differs by species and region and may be controlled by civil law as well as religious laws such as Kosher and Halal laws. A typical procedure follows:
Cattle (mostly steers and heifers, some cows, and even fewer bulls) are received by truck or rail from a ranch, farm, or feedlot.
Cattle are herded into holding pens.