Chickens and other fowl are often fed with grain. Cattle are fed all kinds of grasses. Thus, to a great extent, the eggs, poultry, and beef we eat are the result of grass being processed by an animal’s metabolism.
Tā kā vistas un citi mājputni tiek baroti ar graudiem un liellopi ēd zāli, tad arī olas, vistas un liellopu gaļa ir produkti, kuru iegūšana ir saistīta ar graudzālēm.