Are animals that mix with dogs considered impure, and must clothes be washed if these animals touch them?

Cats are pure (tahir), based on the Prophet's (peace be upon him) saying: "They are not impure (najis); they are among those who frequently circulate among you." Their fighting with dogs does not render them impure (najis), so there is no need to wash any place they touch. What the questioner does by feeding cats brings reward and recompense, and one must be careful not to give in to obsessive whispers (waswas).