Jws seem to firmly believe that before the flood mankind eas vegan or at least vegetarian.
However, in Gen 1:24,25 it says that God created livestock (domestic animals) and beasts of the eart (wild beasts).
Why would Adam and Eve need livestock if they were vegan and naked? Wouldn't need wool or hide for clothing, nor meat for food. Possibly for dairy products only? That also poses a problem as every farmer knows, roughly 50% of births will be males, they're useless to dairy herds so they need to be culled, can't release them because they won't survive in the wild, they still have to be shorn, hoofs maintained etc to keep healthy. Domestic animals need mankind, and mankind needs domestic animals, by design.
Abel was a shepherd, Gen 2:2-4, and sacrificed animals to God, so mankind was familiar with killing beasts. He also knew to sacrifice the fatty pieces because that was considered the best cut of meat, how did he know that was the best? Did God say give me the fat it's my favourite? Or was Abel familiar with the meat and it's various cuts and flavours? Imo logic will go with the latter option.
Noah and family were granted to eat all the animals of the earth and creatures of the sea and birds Gen 9:2,3, but the animals would now be afraid of mankind. To me this means that Noah was now given permission to hunt, they could eat wild animals as well as livestock.
But wid animals would run away, whereas livestock are not afraid of their shepherds and carers.
I believe the reason for this was because post flood the land was saturated and it would take at least a year for crops to be seeded and grow, probably longer because of the condition of the land. Wild animals often reproduce faster than livestock, so would be a quicker and steadier source of food.
I think JWs wave away these logical reasonings in favour of fairy tales, but i really don't think the Garden of Eden was a fairy tale at all.