Bull

Bulls are found in the wild.

They can be tipped
They can be slaughtered if you have a knife better than slate quality (glass or higher).
Attempting to slaughter a bull can cause the bull to run away.
Feeding a bull a pepper produces cattle dung.
Slaughtering, tipping or tickling a bull will grant an achievement.

Use

Slaughtering a bull gives:

A bull assigned to a ranch can be instructed to plough a field for growing vegetables. See Vegetable Field.