foxes need a hunting cool down

This being said from someone who owns chickens and lives out in the country. Foxes are clever and tend to hunt one chicken depending on how hungry they are.

Minecrafts foxes. Slaughter all the chickens instantly. Maybe give them a hungerbar, that wont kill them if empty but if low enough they start hunting, for berries, if none available then chicken and fish but if fed they wont attack more mobs, until hungry again.

foxes are not wolves or coyotes. They take food and leave until hungry again