Industrial hemp for cattle

There are many uses for industrial hemp and cattle feed may soon be one of them. Don’t worry, it won’t make your cows high. Researchers at Kansas State University are studying the nutritional benefits of hemp, and the potential for cannabinoid drug residues to accumulate in meat and milk.

Mike Kleinhenz is an assistant professor at Kansas State’s College of Veterinary Medicine, and co-researcher on the study. He says all parts of the hemp plant could be nutritious for cattle.

"Depending on the plant part, they had varying levels of crude protein. So crude protein in say the flower or the leaves, or even the leftover from the seed harvesting, so that chaff, in the upper 20’s, the 20% range. It would be comparable to alfalfa, so quite a bit of crude protein," says Kleinhenz. "Digestibility on most of these were fairly good, especially when you got away from the stemmy-type pieces."

The biggest downside to hemp as livestock feed is the plant’s cannabinoid content. And if you feed hemp to an animal, do cannabinoids get into its system? They fed some to Holstein steers to find out.

"Basically, we wanted to see if it actually entered the animal, how long does it stay in the animal? And what we found was that when you feed industrial hemp, yes cannabinoids are absorbed in the animal quite rapidly, but they go away pretty quickly as well," he says. "So, the half-life on that is like, 14 hours. The maximum concentration to be cut in half was 14 hours, essentially."

The FDA considers cannabinoid content in food items not safe for human consumption. So the million-dollar question is, at what point is the meat or milk free of residues and safe to enter the food chain? Kleinhenz says the research continues for that answer.