In our dreams, this simple domestic animal can represent a variety of very important and deeply-felt issues. In some cultures the cow is a sacred symbol, representing divine qualities of fertility, nourishment and motherhood. Consider the details in your dream and make attempts to identify the individual, (it could be yourself), to whom the symbolism applies. Additional characteristics to consider when interpreting a dream with cows as one of the primary symbols are passivity, docility and general contentment with life.
The cow is mostly a positive dream symbol, and superstition-based dream interpretation say that grazing cows are symbols of prosperity, contentment and happiness. See also: Animals ... The Bedside Dream Dictionary