Interesting.

She perceived the dog as a threat even from a distance, and immediately attacked, apparently trying to drive it off.

Her reaction to the cat was more like "I'm not sure if you're dangerous or not, but I'd rather not have you so close to my baby." Then she sniffed at the cat, as if she were saying, "What exactly are you?"

Then the cat batted (clawed?) her nose, and it was "Okay, you ARE dangerous! You're out of here too!"