Is water that has been drunk by a pig or a dog suitable for Wudu (ablution), and is the impurity of a dog more severe and malicious than that of a pig?

Some scholars, including the Malikis, have permitted purification with water into which a dog or a pig has licked. The Malikis hold that the saliva of a dog and a pig is pure, and that whoever performs ablution with it and prays, their prayer is valid, although it is preferable not to perform ablution with it if other water is available. The majority of scholars, however, consider the saliva of a dog and a pig to be impure, and consequently, a small amount of water becomes impure if they lick it, making purification with it impermissible.