Vohu Manah, in Pahlavi: Vohuman, or Good Spirit, ensures the presence of God in the soul of the just, and leads them to Paradise. His equivalent is the bovine (the bull or cow which provides the urine or milk to be mixed with the homa of the sacrifice). He is lord of fifth creation, the cow or animal.
Boyce, Mary, Zoroastrians: Their Religious Beliefs and Practices, New York, Routledge, 2002, p. 19
Grimal, Pierre, Larousse World Mythology, Secaucus, New Jersey, Chartwell Books, 1965, p. 190