Feeding high oleic soybeans to dairy cows

High oleic soybeans have been around for more than 10 years, mostly in the eastern United States.  More recently, they have worked their way into the Midwest market, catching the attention of the dairy industry.

High oleic soybeans were developed for the food industry because the oil has a higher concentration of oleic fatty acid and lower concentration of linoleic fatty acid, a polyunsaturated fatty acid (PUFA), leading to longer shelf life and fryer oil life.  In more recent years, researchers have recognized these soybeans with more oleic fatty acid can also increase dairy cow milk fat production.

Whole soybeans and their byproducts serve as an excellent source of essential nutrients to dairy cows.  Depending on how they are processed, soybeans can provide high-quality protein and energy from fat.  Roasted soybeans have traditionally been used as an economical source of rumen-degradable protein, bypass protein and fat, allowing producers to use a homegrown feed in some cases.

Historically, producers have had to limit the amount of roasted conventional soybeans they can feed because their high levels of PUFA can be detrimental to rumen microbes.  PUFA can disrupt normal rumen function and alter rumen fermentation, leading to milk fat depression.

While conventional and high oleic soybeans have similar protein and fat content, they differ in their fatty acid profiles.  In conventional soybeans, less than 25% of the fat is comprised of oleic acid and the remainder is comprised mostly of linoleic acid.  In high oleic soybeans, the percentage of oleic acid is closer to 75% and less than 10% is linoleic acid.  This higher concentration of oleic fatty acids is much more rumen-friendly, reducing the risk of milk fat depression.

Research on feeding high oleic soybeans to dairy cows has been conducted at Penn State University, Michigan State University and the University of Wisconsin-Madison.  A Penn State University study comparing normal to high oleic ground roasted soybeans showed higher milk fat concentration and higher fat yield.  A Michigan State University study comparing increasing levels of roasted high oleic soybeans showed overall higher milk yields and increased fat and protein yields.  The University of Wisconsin study showed an increase in milk fat percentages for mature cows when feeding whole, raw high oleic soybeans versus conventional whole, raw soybeans.

The return on investment with high oleic soybeans will vary by farm, depending on feeding rates, current feed ingredients and feeding strategies.  Feeding rates range from 3 to 8 pounds per cow per day of high oleic roasted ground soybeans.  The opportunity to feed a homegrown protein source is certainly attractive to farms with surplus land base.  In addition, there are opportunities to further reduce purchase feed costs from conventional soybean meal, bypass protein and bypass fat sources.  Herd performance goals include increases in milk fat percentages and yields.

High oleic soybeans are expected to be comparable to normal soybeans in terms of seed costs with no difference in yields or protein and fat concentrations.  In a few areas, producers raising high oleic soybeans have been able to contract for a premium over conventional soybeans.

Like any new technology, there are limitations.  Maturity options may be a challenge for northern locations with 1.9 as the lowest maturity rating currently available.  Growers of high oleic soybeans may also experience limited seed and elevator options.  High oleic beans need to be stored separately from conventional soybeans; anyone wishing to grow them to sell must be near an elevator that is contracted to specifically receive high oleic soybeans.  Weed control also can be a challenge with limited herbicide options.  Future varieties will soon be available with traits that allow for controlling the weed populations.

If land base and logistics allow, raising and feeding high oleic roasted soybeans can be an option to reduce purchased feed costs while having a positive impact on milk component yields.  Work with your agronomist and nutritionist to determine if high oleic soybeans fit in your operation.

This article was originally written for the January 27, 2024, issue of  Dairy Star. Click here for the original article.

About the author:  Barry Visser is a dairy technical specialist based in Minnesota.  He grew up on his family’s dairy farm in northwest Minnesota.  Visser received his bachelor’s degree in animal science from the University of Minnesota in 1994.  He worked as a dairy nutritionist for four years before returning to graduate school to earn his master’s degree in dairy cattle nutrition.  His research focused primarily on transition cows and minimizing pre- and post-calving metabolic challenges.  While a graduate student, Visser also worked as an assistant herdsman for the University of Minnesota-St. Paul dairy herd.  At Vita Plus, Visser works with fellow employee owners to troubleshoot farm nutrition, forage quality and management challenges.