| dc.description.abstract | Thirty mature geldings (mean ± SD; 14.83 ± 2.61 yr; 556 ± 62.77 kg BW) were used in a randomized complete design for a 28 d trial to determine the influence of CBD oil supplementation on the health of mature horses by conducting a blood chemistry panel and evaluating the presence of banned substances. Horses were balanced by body weight (BW) and age, and randomly assigned to 1 of 3 treatments: canola oil (CON; n=10), canola oil with 0.13 mg CBD/kg BW (TRT1; n=10) or 0.12 mg CBD/kg BW (TRT2; n=10). Treatments were top-dressed and mixed onto concentrate that was delivered twice daily at 12 h intervals using attachable feed bags. Diets were formulated to meet or slightly exceed nutritional requirements for mature horses at maintenance. Between meals, horses were maintained in adjacent dry lots and received coastal bermudagrass hay ad libitum. Body weight was obtained, and body condition scores (BCS) were assigned every 14 d. Blood was collected via jugular venipuncture and a blood chemistry panel was performed as well as banned substance testing at the Texas Veterinary Medical Diagnostic Laboratory (College Station, TX). Data were analyzed using PROC MIXED of SAS (v9.4). Model contained effect for treatment, time, and treatment × time interaction for BW and BCS. A covariate was used to account for differences in blood chemistry on d 0 and main effect tested was treatment. Dietary treatments did not affect concentrate intake, BW, or BCS; however, BCS varied over time (P ≤ 0.01) across treatments. Supplementation of CBD did not reveal the presence of banned substances, including tetrahydrocannabinol (THC). A linear dose response was observed in concentrations of serum Ca (P = 0.01). Creatinine levels tended (P = 0.07) to be lower in TRT1 compared to CON while gamma-glutamyl transferase levels (P = 0.03) demonstrated a quadratic response by dietary treatments with CON being lower than TRT2, but values remained within normal physiological limits. Canola based CBD oil appeared to be well-accepted by mature horses, banned substances were not detectible in blood, and blood chemistry parameters were not adversely impacted as a result of supplementation. | |
