Purina Flock Block Poultry Supplement, 25 lb. Bag - Wholesome nutrition - Made from whole grains for a nutritious treat - Mixed-flock treat complements complete feed of laying chickens, ducks, geese and turkeys - Contains oyster shell and grit to aid in shell quality and feed digestion - Backyard happiness - Solid grains encourage birds' natural pecking instinct, to keep them entertained and enrich the coop - Chicken supplement is ideal for laying hens and mixed poultry flocks The Purina Flock Block Poultry Supplement is a treat for laying hens and mixed poultry flocks. Made with whole grains, the chicken supplement block provides nutrients and enrichment no matter the season. In the summer, this chicken supplement encourages natural pecking behavior; and in colder weather, it's a useful boredom buster, giving birds a place to peck besides each other.