THC is popular with some people for its psychoactive effects, while CBD has been shown to have some therapeutic benefits. Also of note is “hemp,” which is the same plant, but a different variety, meaning that the same plant is bred for certain traits. In this case, hemp is grown and used largely for commercial or industrial use, and is bred to have only 0.3% THC (based on the 2018 US Federal Farm Act Sect 297A, hemp must contain less than 0.3% delta-9 tetrahydrocannabinol) is usually about 3% CBD, but some varieties may contain up to 25% CBD. In Canada, all cannabinoids are regulated under the Hemp Act 2018. Industrial hemp must contain less than 0.3% THC, but there is no legal limit to the amount of CBD.
Because hemp is a fast-growing plant, it is also important as a potentially beneficial product for horses, either as bedding and/or a high-fiber feed source. A by-product of hemp is hemp seed oil, which generally contains only marginal amounts of CBD. It should be noted that hemp (or its oil) is not currently approved as an ingredient in horse feed in the United States or Canada, although Hemp Nutrition Alliance Hope to change that.
Cannabidiol has shown many therapeutic benefits to people, including helping people with anxiety, multiple sclerosis, rheumatoid arthritis, and others. In fact, the US Food and Drug Administration recognizes CBD as a pharmaceutical drug for humans. In Canada, it is a controlled substance and its production and use for humans is supervised by Health Canada. If CBD is being sold with a health claim, it must pass through Food and Drug regulations.
However, this becomes more complicated to use with animals. CBD is not approved as a pharmaceutical treatment for animals, however it is also a non-nutritive, often called a nutrient. As we know, much of the nutrient industry is unregulated.
Despite these issues, horse owners (and other pet owners) have recognized CBD as potential treatments for their animals. T
Administering CBD to horses has gained popularity, despite a few research studies looking at safety or effectiveness in horses.
Ellis and Contino (2019) reported improvements in a horse with severe pain sensitivity when fed 500 mg of CBD daily. Another study reported a lower reaction (dismissibility) after 6 weeks of supplementing with 100 mg of CBD daily (Draeger et al., 2021). that in the laboratory A study – conducted in a lab, not in a real horse – by Turner et al. , 2021, reported a decrease in inflammatory cytokines (proteins associated with pain and inflammation) by cells dipped in 4 μg/mL CBD.
Williams et al, 2022 conducted pharmacokinetic studies investigating the absorption and clearance of CBD. A dose of 0.35 mg/kg body weight (body weight) to the horse (approximately 175 mg per 500 kg/1100 lb horse), given orally, showed a peak in blood CBD at approximately 2 hours after feeding and was generally cleared from the system in within 12 hours. A higher dose of 2 mg/kg body weight (about 1,000 mg, or 1 g) also resulted in peak blood concentrations approximately 2 hours later, but it took up to 2 days to clear the system.
It should be noted that metabolites may remain in the system for a longer period.
This study did not report any adverse effects in any of the horses. However, it is important to note that despite the relatively high dose in the treatment of 2 mg/kg body weight, plasma concentrations only reached about 51 nanograms/mL (nanograms per milliliter), well below the effective concentrations of 4 mcg/mL. (micrograms per milliliter) was reported by Turner above (nanograms are smaller than micrograms). Therefore, a horse may need much higher oral doses of CBD for any effectiveness against pain and inflammation. It should also be noted that while the CBD product used in the Williams study did not report the presence of any THC, THC was actually detected in the blood (!).
Regardless of the apparent benefit in horses, both the FEI and the United States Equestrian Federation have included CBD/CBDA on their Prohibited Substances List, meaning that their use in a competition horse is not permitted at any time. Any type of cannabis derivative will result in a positive test, resulting in a fine and the possibility of suspension. In Canada, CBD in equine samples will result in a violation, with the penalty set by the Equine Drug Control Commission.
The legal concerns extend even to those who do not compete, as CBD is still considered a Schedule 2 drug in Canada and veterinarians are not allowed to prescribe these products. This puts the animal owner in the only position to determine if CBD is the right choice for their animal, and scrutinize the source they are getting. It also forces owners to take responsibility for any ill effects that may occur to the animal.
For the latest information on the status of CBD for animals, please visit Canadian Veterinary Medical Association and the American Veterinary Medical Association.