In Spanish, gato is not necessarily attractive (though they usually are) but a cheap sex worker or a promiscuous seductress/tor.

Potro (colt) is an attractive young man
Yegua (mare) equivalent to bitch, an asshole woman
Vaca (cow) same as in English, could be used for someone overweight or dumb
Cerdo (pig) same as English, a filthy/fat person

Marmota and burro (marmot and donkey resp.) someone dumb

Vibora, buitre (snake, vulture resp.) toxic person
Sapo, bicho (frog, bug resp.) someone ugly
Mariposa (butterfly) allegedly or suspected to be gay

Those are the first ones to pop into my mind but I'm sure there's more