Making cattle feed starts with combining the right proportions of energy sources, protein sources, and roughage to meet the nutritional demands of your specific animals. The exact recipe depends on whether you’re feeding a growing calf, a lactating cow, or a finishing steer, but the core process is the same: identify your animals’ protein and energy needs, select ingredients that meet those needs, balance the ration mathematically, mix thoroughly, and store properly.
What Cattle Actually Need From Feed
Cattle at different life stages need different levels of crude protein in their diet, and getting this right is the single most important step in formulating feed. Young, growing animals need the most protein. Feeder calves under 12 months require roughly 10.6% crude protein on a dry matter basis, while growing replacement heifers at around 400 pounds need about 9%. As cattle mature and stop growing, their protein needs drop. A mature bull in maintenance only needs about 5.7% crude protein.
Lactating cows are the exception to the “older means less protein” rule. First-calf heifers in early lactation need around 9.7% crude protein to support both milk production and their own continued growth. For dairy cows specifically, the goal is a milk-to-feed ratio greater than 1.5, meaning each pound of feed consumed should support at least 1.5 pounds of energy-corrected milk. That’s a high bar, and it requires energy-dense, well-balanced rations.
Beyond protein and energy, cattle need minerals. Calcium and phosphorus are the two most critical, and their ratio matters as much as their total amounts. Vitamin A is especially important when cattle are eating stored or brown forage rather than fresh green pasture. A dry cow on stored forage needs about 42,000 IU of vitamin A per day, while a lactating cow needs roughly 59,000 IU per day.
Choosing Your Ingredients
Every cattle ration is built from three categories of ingredients: energy sources, protein sources, and roughage. Your local availability and cost will drive specific choices, but here are the workhorses in each group.
Energy sources: Corn is the standard energy grain in most of North America. It’s high in digestible starch and widely available. Barley and wheat are also used, though they’re processed differently. When grain prices spike, byproducts like soybean hulls can partially replace corn without hurting production. One study found that when corn grain was reduced from 40% to just 1% of the diet and replaced with soybean hulls, milk yield and milk composition held steady.
Protein sources: Soybean meal is the benchmark protein ingredient. Canola meal, sunflower meal, and whole cottonseed are all effective alternatives. Sunflower meal and canola meal can replace soybean meal with little difference in milk production. Cottonseed pulls double duty as both a protein and energy source and can replace soybean meal in lactating cow rations effectively. Dried distillers grains, a byproduct of ethanol production, are another common protein and energy source and can be included at meaningful levels in concentrate mixes.
Roughage: This is the fiber component that keeps the rumen functioning properly. Alfalfa silage, corn silage, grass hay, and chopped hay are all standard options. For dairy rations, target a neutral detergent fiber (basically the structural fiber content) of 39 to 43% for alfalfa silage, 48 to 55% for grass silage, and 40 to 45% for corn silage. Cottonseed hulls and corncobs can partially replace forage fiber in a pinch, though corncobs reduce digestible energy and can hurt milk yield if they make up too much of the ration.
Balancing a Ration With the Pearson Square
The Pearson Square is the simplest method for balancing a two-ingredient feed mix to hit a target protein level. It works anytime you have one ingredient above your target and one below. Here’s the process using a real example from Montana State University.
Say your animals need 11% crude protein. You have chopped hay at 12.25% CP and corn silage at 10.8% CP. Draw a square. Put your target (11%) in the center. Place chopped hay’s protein (12.25%) at the top left and corn silage’s protein (10.8%) at the bottom left. Now subtract diagonally: the difference between 10.8 and 11 is 0.2 (ignore the negative), and the difference between 12.25 and 11 is 1.25. These differences tell you the parts of each ingredient. Chopped hay gets 0.2 parts, corn silage gets 1.25 parts, for a total of 1.45 parts.
Convert to percentages: chopped hay is 0.2 divided by 1.45, or 13.8% of the ration. Corn silage is 1.25 divided by 1.45, or 86.2%. That mix will deliver exactly 11% crude protein. For more complex rations with multiple ingredients, you’ll need nutrition software or help from an extension nutritionist, but the Pearson Square handles straightforward two-ingredient balancing quickly.
Rations for Finishing Cattle
Finishing rations, designed to put weight on cattle efficiently before slaughter, are the most grain-heavy feeds you’ll mix. The conventional approach is to include only as much roughage as needed to keep the rumen healthy. Most finishing diets are formulated with about 8% roughage, sometimes up to 10%. The remaining 90% or more is concentrate: grains, protein meals, and supplements.
This high-concentrate approach maximizes feed efficiency but requires careful management. Cattle need to be transitioned gradually from forage-based diets to finishing rations over two to three weeks. Jumping too quickly to high-grain diets causes acidosis, a dangerous drop in rumen pH that can kill cattle or permanently damage their digestive systems. Step the grain up by a few percentage points every few days while reducing forage proportionally.
Operators who grow their own silage often include more roughage than the bare minimum because it uses homegrown feed and reduces purchased grain costs. Those who buy all their feed and have limited land tend to push toward minimal roughage to maximize the pounds of gain per pound of feed.
Mixing the Feed
Consistent mixing is critical. If one animal gets a mouthful of pure grain while another gets mostly hay, you’ll have digestive problems and uneven performance across the herd. The standard equipment for on-farm mixing is a vertical feed mixer wagon: a tub with vertical cutting augers that simultaneously chop and blend ingredients. These handle everything from long-stemmed hay to grain to liquid supplements.
For dairy operations, the goal is a total mixed ration (TMR) where every bite contains the same proportion of ingredients. You can check mix quality with a Penn State Particle Separator, a set of stacking screens that sorts feed by particle size. A well-mixed TMR should have 8 to 10% of material on the top (coarsest) screen and more than 40% on the middle screen. If the particle distribution is off, cattle will sort through the feed, pick out the grain, and leave the fiber behind.
Load ingredients in the right order. Put dry hay or long-stemmed forage in first so the augers can chop it. Add grains and protein meals next, then liquids like molasses or water last. Overmixing is nearly as bad as undermixing: running a vertical mixer too long breaks down fiber particles and reduces the effective roughage in the diet.
Storing Feed Safely
Moisture is the enemy of stored feed. If the moisture content of a ground feed mixture exceeds 15%, it should be used within a few days to avoid heating and spoilage. Heated feed not only loses nutritional value but can cause digestive upsets when cattle eat it. Mold growth introduces mycotoxins that reduce intake and can damage the liver and immune system over time.
Steam-rolled or tempered grains, which have been exposed to moisture during processing to reduce dust and improve texture, pick up an extra 4 to 8% moisture. That means they need to be fed within one to two days of processing to prevent spoilage. If you’re processing grain on-farm, only prepare what you can feed in that window.
For silages, target dry matter content depends on the storage structure. Corn silage in a bunker should be 30 to 35% dry matter. In an upright silo, aim for 32 to 38%. Alfalfa silage runs slightly drier: 34 to 40% for bunkers, 34 to 42% for upright silos. Proper fermentation produces lactic acid (target 6 to 8% in wet silage) and keeps butyric acid below 0.1%. High butyric acid means the silage fermented poorly and will reduce intake.
Adding Minerals and Vitamins
Most homemade rations need a mineral and vitamin premix added on top. You can buy commercial premixes designed for your region and cattle class, or you can formulate a custom mineral supplement. The simplest approach for a cow-calf operation is offering a free-choice mineral mix in a covered feeder where cattle can self-regulate intake to roughly 4 ounces per day.
For vitamin A specifically, if your mineral is consumed at 4 ounces per head per day, the concentration needs to be about 168,000 IU per pound for dry cows or 234,000 IU per pound for lactating cows to deliver the required daily amounts. Cattle on lush green pasture synthesize enough vitamin A from the beta-carotene in fresh forage and generally don’t need supplementation during grazing season. The need kicks in when they transition to hay, silage, or dormant winter pasture.
Salt is the one mineral cattle will consistently seek out, which is why most mineral mixes use salt as the carrier and intake limiter. Trace minerals like copper, zinc, selenium, and manganese are included at small amounts in commercial premixes and are usually not worth trying to source and mix individually unless you’re running a very large operation with a nutritionist on staff.