Abstract Periodontal disease is considered the main oral cavity disorder in dogs. Essential oils have the potential for use in the prevention and treatment of oral diseases. The antimicrobial activity of Schinus molle L. essential oil (SMEO) has already been reported. Chitosan, a natural product with antimicrobial activity and good biocompatibility has potential in biodental applications. In this study, we evaluated the in vitro antimicrobial activity of SMEO against bacteria associated with periodontal disease in dogs, developed and evaluated the physicochemical properties of a novel chitosan-based buccal delivery system containing SMEO. SMEO showed antimicrobial activity against Gram positive and Gram negative bacteria associated with canine periodontitis, with MIC values of 750 µg.mL-1 for Staphylococcus spp. and Streptococcus spp, 1000 µg.mL-1 for Corynebacterium spp. and 1250 µg.mL-1 for Pseudomonas spp. All formulations evaluated presented adequate physicochemical properties, good stability, and pH values close to buccal pH (5.0–7.0). Chitosan gel loaded with SMEO showed potential as a SMEO delivery system, having the ideal physicochemical and rheological properties (pseudoplastic and apparent viscosities) required for application on buccal tissue. Thus, we can conclude that formulation has the potential to be used for buccal mucosa delivery in the prevention and treatment of periodontal disease in dogs.

A fast and efficient method has been developed and validated for the determination of fipronil in bovine plasma. Samples were subjected to solid-phase extraction (SPE) followed by reversed phase liquid chromatography (LC) separation, using acetonitrile/water (60:40 v/v) as the mobile phase with a flow rate of 1.0 mL/min and ultraviolet (UV) detection at 210 nm. Ethiprole was used as the internal standard (IS). The method was found to be linear over the range 5-500 ng/mL (r = 0.999). The limit of quantitation (LOQ) was validated at 5 ng/mL. The method was successfully applied to monitor plasma concentrations following subcutaneous administration of fipronil in cattle.