Bovine colostrum concentrate preparations derived from cows that have not been hyperimmunized against specific antigens also may provide some benefit via passive immunization for some diseases. For example, a commercial product which is made from large standardized pools of colostrum collected from over 100 cows has been used to treat a number of diseases [22, 23] , including diarrhea caused by diarrheagenic E. coli [67] . Similar preparations from non-immunized cows may provide protection against bacterial toxins that are the cause of diarrhea in AIDS patients [68] . These studies, along with the above mentioned study comparing colostrum preparations from cows immunized against S. dysenteriae or non-immunized cows [63] , demonstrate that bovine colostrum contains significant antimicrobial properties as a result of natural exposure of the cows to antigens of pathogens that may afflict humans.