My Amalie, before her spay, went into a heat like I've never seen in cats before. She made a noise somewhere between a chirp and a purr - no howling - and walked and walked and walked all over the house. Then she laid down and rolled on her back, twisting and turning. She set her affections on Gypsy, a spayed female, and followed her everywhere chirping at her. Poor Gypsy couldn't stand the attention (she's the model for Oscar the Grouch) and growled constantly. I know it wasn't nice, but I laughed quite a bit at the situation. I just hope she didn't hear me