'Mules' in the Bible

They [were] each bringing his gift; objects of silver and objects of gold, clothing, weapons, spices, horses, and mules. {This used to happen year after year}.

Ahab said to Obadiah, "Go through the land to all the springs of water and to all the wadis. Perhaps we may find green grass that we may keep horses and mules alive and that we might not lose any of the animals."