An old teacher of mine, learned voodoo in Haiti where she lived for several years, and she explain us, that a Bocor (witch) or a Ounga (man witch) are strictly forbidden to kill animals or humans. So, that was another kind of ritual, but not voodoo. History Channel was cheating people, but rather be careful of believing everything TV shows.
Voodoo is a very generic term....like Christian. There are many different variations of it and there are a few who still practice animal sacrifice. And, the religions in Africa that Voodoo originated from definitely practice animal sacrifice.
Animal sacrifice is not my thing but I understand why they do it, it makes sense and I don't see anything wrong with it in the way they do it. I am slowly switching over to vegetarianism because of what we in America do to farm animals. Now, that's animal cruelty.