If a beast, donkey, mule, sheep, cow, or camel drinks from water, there is no harm in using it and performing ablution with it. However, if a lizard falls into a vessel of water, the water should be poured out. If a dog licks the vessel or drinks from it, the water should be poured out, and the vessel washed three times: once with earth and twice with water, then dried. As for stagnant water with an unpleasant odor, it is best to avoid it, unless no other water is available. There is no harm in performing ablution with water from which a cat has drunk, and there is no harm in drinking it.
Commentary #4