With the use of bleed air for anti-ice, you're going to see a slight drop in engine performance; either a slight loss of thrust with an attendant increase in temperature, or if compensated by increasing power, an even greater increase in temperature and higher fuel flows.
Any time you're stealing air from the engine, you're robbing performance in one way or another. It may be seen as a thrust decrease/EPR decrease, always as a temperature increase, and depending on the compensation made, as a fuel increase as well. The same is true of opening a third pack vs. leaving it off.