Just from the Jewish side, I don'r have too much time, so I copied it. Should answer part of your question.
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Ritual slaughter is known as shechitah, and the person who performs the slaughter is called a shochet, both from the Hebrew root Shin-Cheit-Tav, meaning to destroy or kill. The method of slaughter is a quick, deep stroke across the throat with a perfectly sharp blade with no nicks or unevenness. This method is painless, causes unconsciousness within two seconds, and is widely recognized as the most humane method of slaughter possible.
Another advantage of shechitah is that it ensures rapid, complete draining of the blood, which is also necessary to render the meat kosher.