Use brewers yeast in all your pet feeds and fruit fly cultures.This is the most important ingredient in a fruit fly culture. Also used in all worm production and cricket food. Full of vitamins and high in protein. Farmers use it all the time in their cattle rations. Brewer's Yeast is a great source of B-vitamins, protein, omega fatty acids, antioxidants, and trace minerals. Protein in brewer's yeast is highly digestible, and a great source of vital amino acids. Brewer's Yeast is also a great source of energy. Used for human, animals & insects!