Cannabidiol (CBD) has garnered significant interest in veterinary therapeutics, yet the pharmacokinetic and safety profiles of its various formulations remain incompletely characterized. This study compared the pharmacokinetics (PK) and health effects of CBD administered as oil (OG, 5 mg/kg) and treats (TG, 50 mg) in 16 healthy mixed-breed dogs over 30 days. Plasma CBD concentrations were measured using liquid chromatography–tandem mass spectrometry (LC-MS/MS), and the PK parameters were analyzed using non-compartmental methods. The CBD-infused rice bran oil formulation (OG) achieved a significantly higher dose-normalized maximum plasma concentration (C_max, 58.40 vs. 21.29 kg·ng/mL/mg) and area under the curve (AUC_0-inf, 305.85 vs. 141.75 h·kg·ng/mL/mg) compared to the treats (TG). The treat formulation exhibited relative reductions in bioavailability, with AUC and Cmax values approximately 2.2- and 2.7-fold lower than the oil group. The terminal half-life (~9.66 h OG vs. 8.52 h TG) and time to peak (2.38 h OG vs. 3.63 h TG) did not differ significantly. CBD accumulation occurred with repeated dosing but declined rapidly post-cessation. The hematological and biochemical analyses revealed no clinically adverse effects, though minor erythrocyte and eosinophil fluctuations were noted. The oil formulation demonstrated superior absorption, while both forms were well-tolerated. These findings highlight the impact of formulation on CBD absorption and support further research into optimized delivery methods for veterinary applications.