At first, the pigs crowded the chickens and, it seemed, were obliged to win. But, as practice has shown, the birds showed fierce resistance and gained the upper hand.
The user reddid used a fence to prevent the animals from scattering, as well as the Battle Mod modification, which allows you to summon a variety of creatures and set them against each other.
1000 pigs vs 1000 chickens from r/Minecraft