SIOUX FALLS, S.D. — Roasted soybeans or soymeal are a common ingredient in the diets of dairy cows because they are a great source of fat and protein — including bypass protein.

Until recently, farmers only had to decide how to process them and how much to feed. Nowadays they also have the opportunity to choose high oleic acid soybeans that bring additional advantages, according to Dr. Kevin Harvatine, Penn State University associate professor of nutrition- al physiology.

At the Central Plains Dairy Expo (CPDE) in Sioux Falls, South Dakota this past Spring, Dr. Harvatine was joined by two dairy producers from Michigan and Wisconsin, for a breakout session: Do high oleic soybeans fit your farm?

High oleic soybeans, known as HO soybeans, are a novel tool in the nutrition toolbox for dairy farmers and nutritionists exploring energy-dense diets with reduced risk for rumen disruptions and milk fat depression, Harvatine observes.

Nathan Brandt of Four Cubs Farm, Grantsburg, Wisconsin and Tim Hood, Hood Farms LLC, PawPaw, Michigan both have multiple years of experience growing, roasting, and feeding HO soybeans, which they shared with a packed room in both panel discussions over the two days.

Four Cubs Farm, for example, milks 1100 cows with 16 Lely robots, shipping 116 pounds of energy-corrected milk, progressing each year by focusing on producing quality feeds on the farm.

They started growing HO soybeans to cut down on the cost of bringing feeds onto the dairy and have been able to offset some of their protein and eliminate purchased protected fat that was previously sourced to palm from overseas.

Brandt says it is a good fit for them because they have the crop acreage to do it, and they see it as a good rotation crop with corn as well.

They started out in 2023 using bags for the beans and then started having a mobile roaster come in. They’ve progressed to putting a 30,000-bushel bin in with their own roaster. Today, they grow 300 acres of the Plenish HO soybeans and buy from a neighboring farm planting another 300 acres. From the beginning, they saw an immediate bump in components and saw their fresh cows take off better. More recently, Brandt shares the improved conception rates reaching elite levels.

Harvatine notes that mobile roasters are popular in his home state of Pennsylvania, and the most important thing is to get a consistent roast.

He grew up on a family dairy farm in Pennsylvania, receiving credentials at Penn State and Michigan State. His research is focused on factors that impact milk fat synthesis strategies to improve milk fat yield.

New questions, products and challenges in fat supplements and optimal methods for balancing dietary fat are his ongoing projects, including how best to use HO soybeans, which he says “offer an opportunity to do homegrown fats” in addition to the decades of work in dairy nutrition optimizing homegrown forages and homegrown protein.

HO soybeans have been around commercially for seven years, and Harvatine has seen interest from dairy farmers and nutritionists increasing in the past two years.

Soybeans contain about 20% fat, Harvatine explains, and conventional soybean fat is normally high in polyunsaturated fatty acids, which are less stable and prone to become rancid more quickly.

“For many years, soybean oil was ‘hydrogenated’ to make margarine, shortening and frying oils, but more than a decade ago we realized the trans fats in these were bad for us,” he said. “Oleic acid is much more stable when frying and storing, which sparked interest in breeding soybeans high in oleic acid and low in polyunsaturated fat.”

Genetic engineering approaches were used to boost oleic acid to 75% in the HO soybean varieties, which means the unstable polyunsaturated fats were reduced to 10%. There are several seed brands on the market.

Penn State University researchers like Harvatine, along with Dr. Alex Hristov, Ph.D., PAS, professor of dairy nutrition, were curious about the dairy nutrition applications from the beginning in 2015.

Even back then, in a Penn State study published in 2017 and funded by a United Soybean Board grant, the HO beans (expelled or extruded not chemically extracted soymeal) showed a surprisingly significant impact on raising the milk fat percentage (0.2%) with no impact on milk volume or other components and virtually no effect on feed efficiency in terms of higher energy-corrected milk.

Today, butterfat is where it’s at in terms of dairy income with BF value in the $2.00 to $3.75 per pound range over the past five to 10 years.

The demand for butterfat is growing worldwide. Demand for butter is up. Cheese uses more butterfat than any other product category as cheese sales have grown substantially over the past decade. Plus, there are new product trends, like the fuller fat cottage cheese craze among young protein-seekers. And, even though domestic ice cream and yogurt sales are down on a total volume basis, the quality, butterfat, and total solids content in domestic sales have increased – moving more butterfat in those categories too.

U.S. dairy farmers are responding by making higher butterfat milk.

Harvatine sees cattle genetics as the primary factor driving milk fat capacity, while dairy nutrition is meeting that capacity, resulting in the general linear increase in milk’s butterfat content nationwide. The national average fat test for 2024 was 4.4%. 

In the research out of Penn State as well as University of Wisconsin, not only did the HO soybeans raise milk butterfat content, it changed the composition. The higher concentration of oleic acid meant a higher level of monounsaturated fatty acids and a reduced level of rumen-disrupting polyunsaturated fatty acids. Milk’s butterfat has a tiny amount of trans fatty acids, and these too were lowered to be even tinier.

The research then and since show the benefits are realized if the residual fat is left in through expelled soymeal or whole roasting of the soybeans. Today, some dairies are even feeding HO soybeans raw, which requires very close management.

Harvatine explains that the seed is widely available today to grow HO soybeans outside of crushing contracts. In some areas, premiums are paid. But for dairies not located close to crushing facilities, getting the HO soymeal can be costly.

In fact, feed companies are now contracting for these beans just for the purpose of nutritionists wanting to use them in dairy rations. (Sensenig’s Feed Mill in New Holland, Pennsylvania, for example, announced on March 31 it broke ground on a project to make more bins for Plenish HO soybeans.)

More HO soybeans are being grown and more is being learned, but it is still somewhat a niche, says Harvatine.

“It’s a really nice opportunity to have another source of fat,” he says, acknowledging some farms are increasing the inclusion percentage of HO soybeans because they are focusing on the fat instead of the bypass protein. Some are also grinding the raw or roasted beans. However, he likes to see particle size stay at least at quarters and halves to slow down rumen access.

“(HO soybeans) are not zero-risk for milk fat depression, but they are a much lower risk for milk fat depression,” he says.

The reduced risk comes from the reduction in the polyunsaturated fatty acids that disrupt normal rumen function, leading to milk fat depression. The higher milk fat yield in the research, he believes, is explained by a decrease in diet-induced milk fat depression.

The oleic acid concentration of the HO soybeans lowers the risk, especially when raising soy inclusion rates from 5% to 10%, some are doing 15% of the diet. Research continues in the quest to find optimal feeding levels based on goals, which vary between nutritionists and farms.

During the breakout session at the CPDE, the producers on the panel talked mainly about feeding soybeans grown on the farm.

One New York dairy farmer said the session was a big eye-opener for him. Overall, the real take home message, he said, was that the inclusion of beans grown on the farm can positively impact butterfat production and lower risk, meaning small and mid-sized dairies wanting to home-grow and cost-control some of the fat in their dairy rations now have the opportunity to do so, while improving butterfat yield at the same time.

According to Harvatine, the milkfat improvement is most notable in herds with lower milkfat to begin with; however, some cows in every herd have lower milkfat and would be expected to benefit.

Feeding the HO soybeans or soymeal also makes space in the ration for other economical byproducts that are higher in polyunsaturated fat, such as distiller’s grains, by reducing the rumen-disrupting polyunsaturated fat levels from these ration soybean sources.