"Pack animal" . "pack donkeys" . . "pack animal" . . "animal transport" . . . "pack" . "Beast of burden" . "pack animals" . . "muleback" . "carry" . . . "Pack animal" . "Pack" . . "animal" . "beasts of burden" . "Pack dog" . "pack work" . "beast of burden" . "pack train" . "pack mule" . "pack horse" . "pack horses" .