Ua hānai mua ʻia ma ke ʻano he ʻīlio mahiʻai, hiki i ka Rat Terrier ke ʻimi i nā koʻokoʻo a me nā parasites ʻē aʻe ma luna a ma lalo o ka honua, a me ka ʻimi ʻana a me ka hopu ʻana i nā holoholona liʻiliʻi. He makaʻala, koa, kūpaʻa, a me ka hoʻolohe, piha i ka ikaika a me ka hoihoi. Aʻo maʻalahi, launa pū me nā ʻīlio ʻē aʻe. ʻAʻole maʻamau ka huhū a me ka hilahila no ka ʻano.
He mau ʻīlio aloha ʻo Rat Terriers, ikaika, a hauʻoli hoʻi e hoʻoikaika nei e lilo i kikowaena o ka nānā ʻana o nā poʻe ʻē aʻe, ʻaʻole lākou e luhi me lākou.
Ma ke ʻano maoli, ʻo ka Rat Terrier he ʻano pilikino a paʻakikī. Pono i ka mea nona. Aloha maikaʻi me nā keiki āu e pāʻani ai. Pono ka launa pū ʻana, ʻoi aku ka nui o nā mahina ʻekolu o ke ola. Me ka ʻole o ka hoʻomaʻamaʻa kūpono, hiki iā ia ke paʻakikī loa a kūʻokoʻa. Hōʻike ʻia nā ʻano makaʻala, hilinaʻi ka manaʻo i nā malihini.