Scientists from the U.S. Department of Agriculture’s Agricultural Research Service (USDA's ARS) and North Dakota State University (NDSU) recently found that cattle fed with hempseed cake, an industrial hemp byproduct, retain very low, food-safe levels of cannabinoids in muscle, liver, kidney, and fat tissues.

At present, highly nutritious hempseed cakes cannot legally be used in food animal rations because the magnitude of Cannabidiol (CBD) and Tetrahydrocannabinol (THC) residues remaining in edible animal tissues have not been characterized. To determine if hempseed cake could be safely used as a source of protein and fiber in cattle feed, a team of ARS and NDSU researchers evaluated CBD and THC residues in the edible tissues of cattle that were fed hempseed cake. Findings revealed that the concentrations of CBD and THC compounds in meat products was much lower than the total amount that global regulatory organizations consider safe for consumers.

Cannabinoid residues were sporadically detected in urine and plasma of cattle during the feeding period, and low levels (about 10 parts per billion) of CBD and THC combined were measured in adipose tissue of cattle harvested with no withdrawal period. In liver, kidney, and skeletal muscle, CBD and THC were below detectable levels in the cattle fed hempseed cake.

The researchers state that, based on the exposure assessment, it would be very difficult for a human to consume enough fat from cattle fed with hempseed cake to exceed regulatory guidelines for dietary THC exposure. The study suggests that hempseed cake with low cannabinoid content can be a suitable source of crude protein and fiber in cattle feed that does not pose food safety risks to consumers.

Final determination and approval for the legal use of hemp products in animal feeds remain with the U.S. Food and Drug Administration (FDA).