A typical female in a beef breeding herd doesn’t start paying her own way at least until her third calf. The first two barely cover development and maintenance costs for the young heifer.

Producers who raise their replacement females recognize that heifer development is one of the more expensive endeavors in the cow-calf enterprise, but they view it as an investment in the future. A high calving rate among first-calf heifers and successful re-breeding in subsequent years generate returns to the ranch. But some producers are taking a new look at heifer development, finding that lower-input and lower-cost systems can improve overall returns, even if reproduction rates drop off somewhat.

Conventional wisdom

Rick Funston, PhD, an animal scientist and reproductive physiologist at the University of Nebraska’s West Central Research and ExtensionCenter, North Platte, has summarized much of the recent research conducted on heifer development.

Traditionally, he says, the rule of thumb has been to develop heifers to 60 to 65 percent of their mature size by the time of breeding, based primarily on the belief that puberty occurs at a genetically predetermined size. Getting heifers to those weights, however — close to 800 pounds for females that will reach 1,200 pounds at maturity — typically requires feeding significant amounts of grain and other inputs, at considerable cost.

New thinking

As input costs rise, Funston says it might be time to re-evaluate heifer-development assumptions. Intensive development systems might maximize pregnancy rates but do not necessarily optimize profit or sustainability. Higher input costs could exceed the value of the extra calves produced in intensive systems, and also, there is some evidence that genetic shifts could be allowing heifers to reach puberty at lighter weights.

Funston cites several studies in which delaying post-weaning gains in heifers until 46 to 56 days prior to breeding did not hurt reproduction but reduced feeding costs.

Ongoing research at USDA’s Fort Koegh Livestock and Range Research Laboratory, Miles City, Mont., comparing lifetime productivity of heifers developed with either unlimited or restricted access to feed through the post-weaning period, has shown that age at time of breeding is more important than weight in determining pregnancy. Several other studies have shown that pasture development of heifers can result in similar pregnancy rates as more intensive development systems but at a lower cost.

Trey Patterson, PhD, is chief operating officer at Wyoming’s Padlock Ranch. He conducted research in heifer-development systems in his former role as an animal scientist at South DakotaStateUniversity and now tests and applies those systems in a commercial setting at the Padlock. “Our thought processes are changing as we gain more knowledge about heifer development,” he says.

The Padlock Ranch, Patterson says, has worked for several years to develop heifers on range to reduce costs, with good results. They do not, however, develop all their replacements with those methods, as forage availability and logistics dictate that some of the operation’s heifers come through a more conventional drylot program. This allows some direct comparisons between the systems, and Patterson says the low-cost program shows favorable results. He cites an example of a group of heifers that calved for the first time in the spring of this year. After being developed and wintered on grass, they reached breeding age about 80 to 100 pounds lighter than a contemporary group of drylot heifers on the ranch. The range heifers had an AI conception rate of 55 percent, compared with 65 percent for the drylot group. After exposure to cleanup bulls, the conception rate was 87 percent for the range heifers.

Patterson says development costs to first conception for the range heifers were about half those for the conventional group. He does not have overall pregnancy rates from natural service for the drylot heifers, because they did not use bulls in that group. Instead, they selected for fertility by only keeping the heifers that conceived through AI and sold the rest as stockers. More on that later.

Patterson says the range heifers remained on grass after calving and spent the following winter outside on tough Wyoming range. Among conventionally developed heifers, he says, body condition often declines during the winter of their first pregnancy, meaning they need extra hay and other feed. The range-developed heifers, on the other hand, are accustomed to finding forage. As of mid-July, the range-developed group had average body-condition scores of 5 or 6, after spending the winter in snowy range conditions with minimal supplementation.

Besides the lower first-year development costs, Patterson says, developing heifers on range builds females that work in the ranch environment over the long term.

Patterson says he does not have scientific data showing behavioral differences, but his personal observations suggest they exist. During the winter on cold, windy days with snow on the ground, cows tend to bunch up in sheltered areas, he says. But his staff has observed those developed on range on the same days, and they tend to spread out, spending more time digging through the snow for forage.

Bred heifers stay, the rest go

In the conventionally developed heifers, the Padlock preg checks at 45 days post AI, sends open heifers to a feedlot and keeps pregnant heifers, which helps select for fertility. In the range-developed heifers, they use a cleanup bull to boost pregnancy rates. Patterson says that over time he would like to combine aspects of the two systems, developing more heifers on range, and using first-service conception among the ranch’s selection criteria.

Patterson concedes that developing heifers on range and breeding them at lighter weights might reduce first conception rates, although that effect on overall pregnancy rates has been minimal at the Padlock. Even so, he says, economics could favor the low-cost system. You can select for fertility and develop females that are well adapted to the environment — that can maintain condition with minimal inputs. Also, selling open heifers as yearlings can be profitable, assuming development costs are low. Patterson says 10 years of data on development costs and sale prices for open heifers show that producers using the system will come out ahead, compared with a higher-cost development program that boosts conception rates.

“Instead of taking heifers and feeding them to the point where they can get pregnant,” he says, “we want to use the environment to help select females that work economically over the long term.”

At the Padlock, Patterson says, managers capitalize the cost of developing heifers at first pregnancy, then depreciate heifers over five years. Higher development costs result in more depreciation. But the benefits of lower-cost development don’t end there. Patterson says he believes the practice continues to provide reproduction benefits and behavioral adaptations to range conditions throughout the life of the animal. “We are comfortable saying we can develop heifers on range, with 1 pound per day of gain through the winter, without any major reduction in reproduction.”

Not for everyone

Producers need to keep in mind that feed is not free and neither is grass, Patterson says, explaining there are opportunity costs associated with developing heifers on range. He stresses that individual producers need to assess their forage resources and availability of other feeds in determining whether range development offers an economic advantage over drylot feeding. In some situations, he notes, developing heifers in a drylot might allow a producer to maintain more cows through the year or bring in yearlings to utilize forage supplies.

Patterson also cautions that dystocia could be a concern when breeding heifers at 50 to 55 percent of mature weight. In most research trials, lighter target weights and range development have not resulted in higher levels of calving difficulty. As long as birth weights in the herd are not too high and producers select proper bulls for breeding heifers, he says this should not be a problem.

While research has demonstrated the feasibility of developing heifers on grass, with minimal inputs, many producers remain skeptical, and the program is not for everyone. Patterson says it is becoming more common for producers to tell him they’ve adopted the low-cost method with good success. When they hear about the program at the Padlock, their response is something like “Good, I can tell my neighbors I’m not so crazy after all.”

Byproducts fit in low-cost development

Where available, distillers’ grains provide a nearly ideal supplement for heifers in a low-cost development program. With about 120 percent the energy value of corn in forage-based diets and good protein levels, and with about 65 percent of crude protein being bypass or undegradable intake protein, the product complements forage and helps fill the nutritional needs of growing cattle. University of Nebraska animal scientist Rick Funston, PhD, reports that research shows feeding dried distillers’ grains to developing heifers not only provides an excellent source of energy and protein for growth but also improves reproduction.

Nebraska researchers recently completed a two-year study at two locations, evaluating the effects of dried distillers’ grains as an energy supplement for developing heifers. They found that supplementing beef heifers with dried distillers’ grains during development did not affect age at puberty and improved artificial insemination conception and pregnancy rates compared with a supplement similar in energy, crude protein and fat.

When he formulates custom supplements for range heifers, Padlock Ranch COO Trey Patterson, PhD, says he aims for something very close to distillers’ grains in terms of energy, mineral and protein content, and the level of bypass protein. The Padlock Ranch operates a feedlot and imports dry distillers’ grains for use in finishing rations. He says he would like to use more as a range supplement, but its loose formulation makes it difficult for supplementing cattle spread out over large areas of open range.