What is the ruling on cats eating feed composed of impure substances such as blood and bone, if their transformation [into pure substances] before manufacturing is not confirmed? Is the impurity of cat saliva considered a legal impurity if it dries and leaves no trace, and does impurity spread in this case through ablution? Does impurity transfer if its location dries and then becomes wet with water or sweat and touches a pure location?

The default ruling concerning impure fodder is that it does not undergo transformation [into a pure substance]. A cat licking your hand does not cause harm because the cat's saliva purifies its mouth. The Prophet, peace and blessings be upon him, informed us that it is not impure, and he performed ablution with its leftover water, even though he knew it ate mice and impurities. The jurists have concluded that the water from which a cat drinks after eating an impurity is pure, whether the cat disappears after eating or not. This is due to the pardon granted concerning it and the difficulty of guarding against it.