The two current answers are good, but I feel something is missing1
As Carlos Alejo points, "de salón" means that it is to put into the living room. The living room is (and specially more in the old times) the room where a family would put its most delicate and expensive wares and stuff, for everyone visiting them to see. So this brings two additional ideas:
the cat is pretty, precious.
the cat is a domesticated being; you would not put a wild animal in your living room, as it was a risk for all your other precious stuff. This one idea contrasts with the image of the tiger.
Also, as for Krauss answer, I can not help thinking that with "mínimo" the author also plays with the "minino" word, which is a familiar term for "cat". Even if the only correct interpretation is that of Krauss answer, everytime I read the word "mínimo", in my mind it doubles the "cat" reference.
Not surprising, as poems and other lyric works are often way more difficult to fully
interpret than other works and there is a very important subjective component.