Do villagers kill animals in Minecraft?

I've been playing in Minecraft for a long time in a world where I and friends have built a village where we also keep animals and where villagers live. Here's the question: Do the villagers kill the animals or die alone because I just found out when I was playing that almost everyone is dead

Which version are you playing on? And on which console?

If they are chickens they are killed by wild ocelots, which are available in the new versions in every village: For the 1.14 - 1.15

if they are sheep, however, it may be that if your village is in a spruce forest, foxes will attack your sheep: For the 1.14 - 1.15

however, if you have wolves near the village, these sheep will also kill unless they are tamed: for all versions

Maybe write what animals it is

So Villager don't kill anything.

I don't know how it is at the moment but I think animals sometimes despawn.

Sheep are also killed by wolves and chickens by Ocelots (possibly from cards too?).

I'm not so sure about foxes. I think chickens are killed by them too