BREWERS YEAST is The Natural Alternative ® for dogs and cats. Tasty and nutritious, BYS® is a pure and natural high potency food supplement for your dog or cat. This organic supplement contains B-Complex Vitamins and is fortified with Zinc and Garlic to reduce shedding and promote healthy skin and coat. The abundant amount of protein (amino acids) and B-Complex Vitamins in BYS® provide the Essential Building Blocks of Life. All Natural Ingredients No Preservatives