Hemp Residue in Animal Feed: Species-Specific Limits and Safety Constraints

The research trail into hemp processing waste as a feed additive extends beyond a single case study. After evaluating milk residues in cows in 2025, researchers at Oregon State University assessed cannabinoid levels in beef. In August 2026, a study published in Poultry Science examined broilers, showing that high inclusion rates of the additive negatively impact growth metrics. This body of work highlights the dual nature of the material: it is a potentially valuable resource, yet it operates under strict safety and productivity constraints. The focus is on the spent biomass remaining after cannabidiol (CBD) extraction. This residue retains nutritional components and trace amounts of cannabinoids, including psychoactive tetrahydrocannabinol (THC). For agricultural producers, this offers a way to integrate a byproduct into feed production rather than discarding it. For toxicologists and regulators, the central question is how much active compound migrates into food products and how quickly animal bodies clear them after feeding stops. The series of investigations builds on a study published in the Journal of Agricultural and Food Chemistry in May 2025. In an experiment involving 18 Jersey cows, a diet containing 13% hemp residue over 28 days resulted in less than 1% of consumed cannabinoids transferring to the milk. However, even this minimal migration presented a theoretical risk: the THC dosage could have exceeded the acute reference dose. After the additive was removed, THC was no longer detected in milk after 12 days, while it persisted longer in adipose tissue. This indicates that the rate of clearance in milk is not a universal indicator of whole-body detoxification.