Why isn’t hemp in animal feed? That’s the question the National Industrial Hemp Council of America (NIHCA) and the Association of American Feed Control Officials (AAFCO) discussed in a recent virtual meeting regarding overcoming challenges and gaining approval for the potential feed option.
Dr. Massimo Bionaz, associate professor in dairy nutrigenomics at Oregon State University, said spent hemp makes an attractive feed on paper. Looking at fiber, hemp is in the same range as alfalfa. It has a high level of protein as well as a little more fat and a little more omega-6 than alfalfa. It’s higher in all important minerals than alfalfa except for iron and potassium.
Bionaz spoke of three experiments he ran with lambs, dairy cows and broiler chickens, feeding them spent hemp biomass. The goals were to see if it was safe to feed the biomass to livestock; to measure the effect of hemp on bilirubin in their blood; and if the hemp affects their livers.
Per the Bionaz lab, the study’s long-term goal is “to implement the safe use of hemp byproducts in livestock diets and take full advantage of their nutritional and potential medicinal properties to improve animal health and the quality of animal products. The objective of the present proposal is to generate fundamental data for the legalization of spent hemp biomass to be used to feed livestock and creating an Extension program to connect producers with the hemp industry. The determination of cannabinoids residuals in milk and meat are essential to obtain FDA approval for use of hemp byproducts in ruminant diets.” The cow project is ongoing (beginning in 2021 and ending in 2023); the lamb study ends this year.
Research is also happening at North Dakota State University with Dr. Kendall Swanson, associate professor in the Department of Animal Sciences. He is specifically looking at hemp seed cake, a byproduct of pressing seeds for oil, for livestock feed. In the first of two experiments, Swanson looked at growth in finishing heifers. They were fed 20% hemp seed cake or distillers’ grain; it was found that the heifers fed hemp seed cake had 8% lower average daily gain.
The second experiment was a digestion study to understand that difference in performance. “We found hemp seed cake is quite high in fiber and higher in fiber than distillers’ grain, and fiber is less digestible, and it’s likely why we saw the slight decrease in gain,” Swanson said. The other nutrients in the cake are very digestible, so he believes there’s a lot of potential for it as a protein source.
“The main thing is cattle producers need to be sure that their animals are healthy and are being taken care of,” Swanson said. “Next, there’s the cost of product and how it influences growth, milk production or whatever product they’re producing. People are looking for alternative feeding ingredients. There’s a lot of interest to find lower cost feed ingredients when the ones you typically feed aren’t available.”
The FDA’s Center for Veterinary Medicine (CVM) will be the eventual reviewers of the data gathered from projects like Bionaz’s and Swanson’s. Charlotte Conway, deputy director with FDA-CVM, said, “There’s a lot of active research going on … and we’re happy to meet with folks designing and undergoing studies to define what information will be useful to have.” The FDA needs proof hemp is safe for animals and then for the human food supply. Conway said right now they have a lot of questions about how residual cannabinoids might affect safety. (Swanson said he’s seeing very little transference, with any cannabinoids gone after about a day in livestock’s plasma, blood and liver tissue.)
The FDA maintains a list of substances that are Generally Recognized as Safe (GRAS). Hemp grain derivatives including hemp seed oil, shelled hemp seed and hemp protein have been approved by the FDA as GRAS for humans since 2018. “GRAS in humans is based on limited consumption but may not apply to livestock where the hemp-based feed may be a major part of its diet for the lifespan of the animal,” explained Dr. Craig Schluttenhofer, research assistant professor of natural products at Central State University. He has raised concern that lifetime consumption of hemp-ingredients may lead to bioaccumulation of cannabinoids in livestock. “The use of GRAS data in feed applications depends on the similarity of the GRAS product to the feed ingredient,” he added.
Erin Bubb, division chief of agronomic and regional services with the Pennsylvania Department of Agriculture and the 2021 president of AAFCO, commented, “Industrial hemp presents a fantastic opportunity as a really good nutrient source for animal food. We’re on the cusp of having that become available. It’s an opportunity for American farmers and American industry and our animals.”
The bottom line in seeing hemp approved as animal feed is what it will cost producers and what it will do to animal health and performance. As the hemp industry expands, it will create more and more byproducts, and the ag world needs to find a safe way to use them.
If you’re interested in learning more about this opportunity, the first ever Hemp Feed Workshop is scheduled for Oct. 26 and 27 at Oregon State University. Read more at blogs.oregonstate.edu/hempfeedworkshop.
by Courtney Llewellyn