CBD from cannabis reduces stress in fish, Scottish scientists find

A cannabis derived compound could help reduce stress in fish being transported for sale, Scottish researchers have found.

Scientists at the University of the West of Scotland (UWS) in partnership with Waltham Petcare Science Institute found adding CBD to water in which ornamental fish are transported in can help to improve their welfare after shipment.

CBD is a natural compound known for reducing anxiety, inflammation, and pain.

Variatus Platys, a popular breed of aquarium fish, were transported in water infused with CBD in an experiment, with results showing a drop in stress-related behaviours in the fish such as biting, chasing and erratic swimming.

More than 125 countries across the world are involved in the multi-billion-pound ornamental fish trade, which sees more than one billion fish transported each year.

The trade sees fish transported far from their place of origin to be placed in home aquariums, decorative tanks and ponds

However, stress caused during transportation can weaken immune responses in the fish and increase their risk of disease. Anxiety-induced behaviours can result in physical harm, both of which require fish to be quarantined and treated before they can be sold.

The study found adding CBD to transportation water produced a calming effect by potentially modulating neural pathways related to fear, with no detrimental impact seen to the protective layer of mucus which covers fish skin.

Researchers say the findings highlight the potential for CBD to be used within commercial water conditioners to reduce the effects of transport stress within the trade, presenting a welcome welfare boost to the industry.

Professor Katherine Sloman from UWS said: “Improving the welfare of fish transported internationally is of importance both ethically and economically. Within the ornamental fish trade, we know that transport-induced stress can lead to erratic or aggressive behaviour, which can exacerbate levels of anxiety and potentially lead to physical damage.

“Our research shows that a relatively small change to the way ornamental fish are transported, such as adding CBD within commercial water conditioners, could transform the industry and help safeguard the wellbeing of countless fish.”

Dr Donna Snellgrove, fish research manager at the Waltham Petcare Science Institute, added: “Improving the welfare of fish during transport by minimising stress is important to ensure the health of fish within the trade. We are proud to be able to establish scientifically supported solutions that will make a difference to such a large number of fish.”

The research directly addresses the United Nations Sustainable Development Goals, particularly Goal14, Life Below Water, and Goal 17, Partnership for the Goals.