Cat urine is so awful b/c cats need a high protein diet, and when the nitrogen is taken off an amino acid it has to go somewhere. So it goes to urea which is excreted in the urine. There are microbes in the environment that convert urea to ammonia. Ammonia reeks. Cats have lots of urea in their pee, so there's lots of potential for ammonia, hence cat pee smells horrid.

Also, cats do not cover when they are the dominant cat in their territory. If they're the boss, there is no need to mask their scent from other cats. If a cat is not the dominant cat, they will cover their poo, as poo is part of scent marking, and leaving uncovered poo is like saying "this is MINE!"

...............CherryHorse Blog..................