Why are feedlot cattle commonly fed grain and legumes?

Feedlot cattle are fed high-energy diets consisting of grains and legumes, such as corn and soy, primarily to support maximal growth and weight gain. This intensive feeding strategy is designed to finish cattle for market efficiently, producing heavily marbled beef that historically commands higher prices.12

By restricting movement and providing a calorie-dense ration, feedlots minimize the energy cattle expend on foraging, allowing them to convert feed into body mass more rapidly. While this grain-based approach is highly effective for weight gain, it is not the natural diet for cattle, which are ruminants evolved to digest fibrous forage. Consequently, the shift to grain-heavy rations can alter gut pH and microflora, sometimes leading to health complications that require careful management.2