Purina® Layena® Crumbles optimum nutrition designed specifically for healthy birds and nutritious eggs. This 16%-protein, high-calcium ration is carefully formulated with prebiotics, probiotics, and yeast to support top-producing laying hens once they reach 18 weeks of age. Featuring Purina’s Oyster Strong® System, it ensures strong eggshells by providing oyster shell, a superior calcium source. The oyster shell particles are larger than limestone, allowing them to remain in the digestive tract longer and supply calcium over an extended period, which is especially beneficial during the night when eggshell formation is rapid and dietary calcium intake is limited. Model Number: