Why did ADVENT kill all domesticated animals

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Why did ADVENT destroy all domesticated animals after establishing a new world order? How did they accomplish it?

After the ADVENT Coalition was formed, they outlawed and apparently euthanized all farm animals and pets owned by humans. This is referenced in several pieces of lore in-game, and Lily suggests that it's been a while since "anyone has even seen a cow."

What was their motivation behind doing this? It does not obviously fit into any of their plans, either the short-term plan of world domination or the long-term plan of The Avatar Project.

Furthermore, how did they accomplish it? There are over a billion cows on earth (and more than twice as many chickens than people), and genociding them seems like it would be an enormous task, not counting the task of feeding humanity without animals on entirely artificial sources. I suspect that this would not be worth the time of the alien overlords. How would they have performed this sweeping extermination of domesticated animals?

Best Answer

Most often extraterrestrials are identified and alerted to owners by domesticated animals, like dogs, cats, parrots, etc.

Since Advent has actually become a surrounding of people but in a way to sway their alertness, it sounds as normal act to prohibit anything that would go against them or serve as base for rejection.

Feeding species with its own remains (in any form) has proven to be overly bad idea, for example mad cow diseases, and I would expect the same for humans (let's not go into topic of cannibalism yet). Except if broken down to prebiotic soup and syntethizing something from that.