"You shall not plow with an ox and donkey together"—Deuteronomy 22:10.
It is forbidden to cause animals of two species to work together, e.g., to have them jointly plow, thresh or pull a wagon.
Biblically, this prohibition only applies if one of the animals is kosher (e.g., an ox) and the other is of a non-kosher species (e.g., a donkey). The Sages, however, extended this prohibition to apply to any two species.
