Wow. Watching "Raw Nature" on APL, they were doing snake milking and told how they make antivenom. According to the little dramatization, they mix four different types of snake venom and inject the horse in small doses so that it develops an immunity, and then they take the antibodies from the horse to create an antivenom for humans! How cool is that!
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Explain how antivenin is produced and whether antivenin given for a snkae bite provides lasting immunity? - Yahoo! Answers