The Suri or Surma people are located in southwestern Ethiopia. They drink blood by cutting a cow's carotid artery and it bleeds out at least two litres of blood into a calabash. Some of them drink so much cow blood they vomit.
Why do they drink cow’s blood?
It is some sort of energy drink. The warriors drink it ahead of the donga or stick fighting battle because it is believed to give them strength and keeps them fit.
The winner of the donga fight gets to choose any woman he wants and I guess that is enough incentive to fight to the death, the women are also happy to be chosen.
During the donga fights, all limits are off, even though you are not supposed to kill the other party, some people die or are maimed and seriously harmed.
When someone kills his rival in a donga fight, he has to buy 20 cows for the deceased family or give them a woman.
Owning cows was seen as a sign of wealth and influence. Cattles are used as bride price and a man who wants to get married must have at least 60 cows.
Cows also have important resources - milk so they are cherished, they are also used for sacrifices to the gods.
I know you are thinking is drinking animal blood even healthy at all? Well, in some quantities, it is alright and has some nutrients but in excess, it is a very bad idea.
This is because the blood might have pathogens that can infect you, also because drinking blood leads to excess iron in the blood and this causes haemochromatosis, liver damage, dehydration, a buildup of fluid in the lungs, low blood pressure, and nervous disorders.