Backyard Chicken Zyfend A Digestive Booster Supplement, 30 Milliliters, Treats 90 Gallons of Water 30 Milliliters Backyard Chicken Zyfend A, treats 90 gallons of water Ideal for all domestic poultry and waterfowl in the presence of harmful intestinal parasites, including worms Proprietary formula contains targeted natural enzymes, selected essential oils and other key ingredients Designed to help offset the detrimental effects of worms and other parasites Made in the USA