No producer likes to spend money on supplemental feed for cows. But, as forage becomes dry, dormant or scarce, it may be necessary.

To help you design a budget-conscious protein supplement program for cows on grass, BEEF visited with three cattle nutritionists to find out, “What works best?”

When To Supplement

“Normally, feeding supplemental protein is necessary and justifiable when the available diet does not meet an animal's nutritional requirements,” says Ed Huston, an emeritus beef cattle nutrition professor from Texas A&M University.

That typically occurs when grass pastures become dry and dormant, and protein content in the plants drops off, says Jan Bowman, a beef cattle nutritionist at Montana State University.

“If there's a lack of forage due to drought, or when forage gets dry in late summer, feeding cattle supplemental protein can give a boost to forage intake and digestion. It's meant to complement the forage,” she says.

Protein supplements also can be important with winter grazing. “Dormant winter range forage is usually very low in protein, making a protein supplement beneficial,” Bowman says.

The periods of calving through breeding are also critical nutritional periods for cows, “but if you are feeding a good-quality hay during that time, the protein content may be enough that another supplement isn't needed,” she adds.

Both Huston and Bowman say a common mistake producers make is providing supplement when cows don't need it.

“Often, personal preference leads producers to feed more supplement than is necessary for economic return,” Huston says. “Much of it hinges on how a producer reacts to seeing a fat cow vs. a thin cow.”

To know when protein supplements are necessary, Huston says, takes a critical eye.

“In a cow-calf operation, watch the cow's condition. A body-condition score (BCS) of 4 to 6.5 is a good target. If her BCS gets above or below that, something needs to be done.

In a stocker situation, rate of weight gain is typically a good indicator of whether supplemental feed is necessary.”

Bowman adds, “Evaluate the protein content of the available forage and estimate how much animals are consuming to determine how much protein they are getting.”

As a rule, high-producing cows need up to 3 lbs. of crude protein/day during lactation, she says.

How Often To Supplement

“Most nutritionists agree that it's best for animals to have all the nutrients they need every day. However, infrequent supplemental feeding of cattle on pasture — three times a week or weekly — produces satisfactory performance and actually has some benefits,” says Huston.

He reports that performance of cows fed a weekly protein supplement is comparable to that of cows supplemented daily or three times a week.

“We haven't found any ill effects of feeding a week's worth of protein supplement at one time,” Huston explains. “For instance, rather than putting out 2 lbs./head/day, you're providing 14-15 lbs./head at that one weekly feeding. We've traced blood/urea levels, which are a good indicator of protein status of the animal, and found that after consuming the weekly feeding, the animal's blood urea level goes up and stays high for five to six days.

“So, we know offering a weekly protein supplement gets them well-dosed with protein, like stockpiling, and by the time the animal's blood/urea level goes back down it is within a day or two of being supplemented again,” he says.

Huston says the advantages of weekly feeding over daily feeding are decreased time and labor expense. Another benefit appears to be an alteration in the animal's behavior pattern.

“When animals are fed daily, you often find them waiting at the gate or running across the pasture to meet the feed truck, which reduces grazing time,” Huston explains.

“We also seem to get a better distribution of feed among animals that are fed infrequently, due to a reduced bullying effect,” he says. He explains that the perceived unlimited amount of feed — compared to putting out a limited amount — likely causes animals not to fight and instead eat in peace.

The bottom line, Huston says, is that infrequent feeding works well with protein supplements.

“Feeding three times a week is the optimal, but weekly feeding is less expensive than daily feeding and offers satisfactory performance,” he says.

The only caution is to be certain none of the ingredients in the product are dose related for health. If an ingredient needs to be fed in low doses on a frequent basis, a once per week feeding would be lethal, Huston explains. Also, energy supplements shouldn't be offered in large, weekly amounts to prevent the animal from overeating starch and getting sick.

How About Self-Fed Supplements?

The convenience of self-fed or self-limiting supplements has helped bolster their popularity, but individual intake can vary widely with such systems. Some cows may not consume any supplement, while others may consume large amounts, cautions Montana State's Bowman.

“When feeding a form of supplement that targets individual consumption, if animals don't eat it, they may not get the nutrients they need. Or, some animals may be eating too much and costing the producer money,” she says.

Bowman says most commercial products have an intake limiter in them, which helps minimize over-consumption. She adds that making sure there are enough tanks or blocks for the number of cows will reduce variation in intake, and adds, “In several studies that we've conducted with self-fed supplements, we've seen very uniform intakes.”

However, those animals that don't consume the supplement — and need it — can be a concern.

To address that dilemma, she suggests introducing animals to the supplement in a drylot setting before being put out on range; placing the supplements in areas animals will frequent — near water or preferred grazing areas; and sorting older boss cows into separate groups from younger animals that may require more supplement.

When considering self-fed supplements, Bowman also offers these tips:

  • Match the product's target intake and protein content with the amount of supplemental protein needed.

  • Price supplements per pound of protein, as you would do with other feeds.

  • Some self-fed products will put a trace mineral package in the product which increases costs. “That package may not be necessary if you already have a mineral program in place,” she points out.

  • Feeding supplements infrequently, like Huston suggests, may be another alternative. The ability to feed weekly or three times per week can reduce labor costs associated with hand-fed supplements, Bowman says.

Where Do Byproducts Fit?

Wheat midds, corn gluten feed, dried distillers' grains and soy hulls are some of the byproducts that are common protein supplements, says beef nutritionist Greg Lardy of North Dakota State University's Department of Animal and Range Sciences.

Lardy has found many byproducts work well, and says, “There aren't too many nutritional mistakes you can make when feeding byproduct, because the starch has usually been removed by the ethanol or milling industry, leaving just fiber and protein.” However, there are some considerations:

First, it's important to identify the correct nutrient deficiency that needs to be supplemented in the herd. For instance, Lardy says if degradable protein for a dry pasture situation is needed, oil seed meals, such as canola meal or sunflower meal — which typically contain 30-40% crude protein — may be a good choice. Conversely, soyhulls may not provide enough protein in some situations, he says.

He reports that another common mistake with byproducts is not taking into account some of the hidden costs, particularly freight and transportation.

“In some scenarios after paying for delivery, a locally available commercial supplement may have been just as economical,” he says. “Most people who use byproducts effectively are aggressive at negotiating. They also look at volume discounts through railcar loads or back-haul opportunities.”

Also, take into account storage considerations. For instance, wheat midds should be stored in bins with an aeration fan to keep mold development to a minimum.

And, depending on the product, pellet quality can be an issue. “Oilseed meals often pellet better, whereas dried distillers' grains are difficult to pellet due to fat content,” Lardy says.

Final Tips

  1. Watch your forages

    Huston advises paying close attention to the forages available: “Gain all the knowledge you can on plant species, their nutrient content and growth cycles.”

    Testing forage nutrient content is also a good idea but, once a history of forage analysis is developed, it doesn't need to be done annually, he adds.

    Additionally, Huston advocates using a rotational grazing system and trying to match peaks in available forage nutrients to the time of the cow's greatest nutritional needs — usually shortly after calving through breeding.

    Growing forages are typically highest in nutrient quality. Dormant forages will support dry, gestating cows, but are usually not suitable for lactating cows, says Greg Lardy of North Dakota State University.

  2. Consider sorting

    “The better you can sort animals into uniform feeding groups to better target their needs, the better off you are,” says Huston. For example, he suggests sorting thin or younger cows from older boss cows. “When fed in one large group, intake can be variable. Often, those who need nutrients the most get the least due to the bully factor,” he adds.

  3. Evaluate different protein types

    Huston suggests utilizing a natural protein when possible.

“Urea or non-protein nitrogen is only about 75-90% as effective as natural proteins. So unless there is a real cost savings, use natural protein based on a price vs. protein content ratio,” he says.

Lardy suggests considering field peas, which contain 22-24% crude protein, as an option as well.

And, Bowman says not to underestimate alfalfa hay. “Year in and year out, alfalfa hay is an inexpensive source of supplement protein,” she says.

Kindra Gordon is a freelance writer based in Spearfish, SD, and a former BEEF managing editor.

Supplementing Energy

While protein supplements work to complement available forage, energy or grain supplements may be needed to stretch forage supplies or boost performance on stockers.

“Energy or grain supplements are typically used as a substitute for forage,” says Montana State's Jan Bowman.

For instance, if forage is in short supply due to drought, grain could be supplemented to take grazing pressure off the grass.

“This can be economical if grain prices are low,” Bowman says.

Supplemental grain may also be needed for stockers if the forage digestibility is lower than the animal's growing requirements.

Wheat midds and soyhulls can be used to stretch forage supplies as well.

“These products generally contain low amounts of starch (soyhulls don't have any), but contain digestible fiber, so the negative effects of starch on forage digestibility are not an issue,” says Lardy.

But, extra energy usually isn't necessary for cows grazing medium- to high-quality forages. When forage is adequate, feeding grain can decrease the animal's intake and digestibility of the forage — and cost you money, says Texas A&M professor emeritus Ed Huston.