Here's what the SRD says for Cat, Big
Starting statistics: Size Medium; Speed 40 ft.; AC +1 natural armor; Attack bite (1d6), 2 claws (1d4); Ability Scores Str 13, Dex 17, Con 13, Int 2, Wis 15, Cha 10; Special Attacks rake (1d4); Special Qualities low-light vision, scent.
7th-level advancement: Size Large; AC +2 natural armor; Attack bite (1d8), 2 claws (1d6); Ability Scores Str +8, Dex –2, Con +4; Special Attacks grab, pounce, rake (1d6).
It doesn't mention anything about minuses (AC/Atk Roll) when it gets the 7th level advancement. Does this imply it doesn't get bonus in cmb and cmd?