Can CBD soothe mourning elephants? A Polish zoo is about to find out

A zoo in Poland plans to test cannabidiol — also known as CBD, a chemical found in cannabis — on its elephants, for stress relief.

According to the BCC, the Warsaw Zoo's decision follows the March death of Erna, the elder elephant in the herd. Elephants are matriarchal, meaning older females lead the herd, so it's no surprise that the three younger elephants have shown signs of stress since her death. Zookeepers hope the CBD will help calm the tense animals; elephants get stressed out easily and are relatively easy for the zoo to keep an eye on, so they're good candidates for testing the substance, which is touted for its calming effect on humans, the zoo told BBC.

As Live Science previously reported, CBD is one of a range of chemicals found only in cannabis plants. But unlike tetrahydrocannabinol (THC), marijuana's main psychoactive ingredient, CBD doesn't cause humans to get high

Related: 25 odd facts about marijuana 

CBD is an increasingly popular substance in the natural wellness industry, and there's anecdotal evidence to suggest it's effective for treating anxiety and other ailments. Proponents of the compound have hailed CBD's healing effects for a wide range of physical and mental illnesses, such as depression and cancer. However, due to U.S. laws regulating the production, use and testing of marijuana products, research on the effects of CBD is limited, although one clinical trial published in the New England Journal of Medicine in 2017 did find that CBD reduced seizures in people with Dravet syndrome, a rare form of epilepsy. As Live Science reported, some early studies have suggested that CBD may work to combat anxiety, and psychosis, while others indicated that it's no more effective than a placebo.

And, of course, all that research describes the effect of CBD on humans. No research yet exists to indicate how the cannabinoid will impact elephants, though CBD companies do make products targeting dogs and cats according to the American Kennel Club, and research into veterinary use of the substance is ongoing.

Moreover, scientists at Tarleton State University’s Equine Center in Texas are giving horses CBD to see whether the substance affects inflammation, stress and problematic behaviors in these animals, according to a statement from Texas A&M University. Results are expected to come out as soon as next year.

The plan at the Warsaw Zoo is to first treat Fredzia, a younger elephant who had the strongest reaction to Erna's death, according to the BBC. Researchers at the zoo have already collected feces, saliva and blood from the animals to measure their levels of cortisol, a chemical associated with stress, before the CBD trial. Scientists will keep monitoring cortisol levels in the elephants as they feed Fredzia — and eventually the other elephants — the cannabinoid, the BBC reported

Originally published on Live Science.