Novel amoxicillin nanoparticles formulated as sustained release delivery system for poultry use.

Amoxicillin is used in the treatment and prevention of a wide range of diseases in poultry breeding. However, its short half-life and low bioavailability restrict its clinical application in these species. Entrapment of drugs into polymeric nanoparticles (nps) presents a means to improve gastrointestinal absorption and oral bioavailability of drugs. This study was aimed to overcome limitation of amoxicillin use in poultry breeding. Amoxicillin was loaded into sodium alginate-polyvinyl alcohol (NaAlg-PVA) blend nps, and characterization of the prepared nps was performed. For pharmacokinetic study, commercial male broilers were used and comparative pharmacokinetics of free and nanoparticle form of amoxicillin were investigated. Twenty-one broilers were divided into three groups. All groups received 10 mg/kg drug. Blood samples were collected, and drug plasma concentrations were determined by HPLC. The results demonstrated that the particle size, zeta potential, encapsulation efficiency, and loading capacity of the nps were 513.96 ± 19.46 nm, -45.36 ± 1.35 mV, 43.66 ± 3.30, and 12.06 ± 0.83%, respectively. In vitro drug release exhibited a biphasic pattern with an initial burst release of 18% within 2 hr followed by a sustained release over 22 hr. The pharmacokinetic results showed that amoxicillin nps have higher bioavailability and longer plasma half-life (p < .01) than free amoxicillin. These results indicate that amoxicillin nano formulation is suitable for oral administration in broilers.

Comparison of the pharmacokinetic profiles of two different amphotericin B formulations in healthy dogs.

This study was conducted to compare the pharmacokinetic profiles of conventional (Fungizone® ) and liposomal amphotericin B (AmBisome® ) formulations in order to predict their therapeutic properties, and evaluate their potential differences in veterinary treatment. For this purpose, twelve healthy mixed breed dogs received both drugs at a dose of 0.6 mg/kg by intravenous infusion over a 4-min period in a total volume of 40 ml. Blood samples were collected at 0, 0.5, 1, 1.5, 2, 3, 4, 8, 12, 24, 48, 72 and 96 hr after dosing, and concentrations of drug in plasma were determined by high-performance liquid chromatography (HPLC). Pharmacokinetics was described by a two-compartment model. Although both formulations were administered at the same doses (0.6 mg/kg), the plasma pharmacokinetics of liposomal amphotericin B differed significantly from those of amphotericin B deoxycholate in healthy dogs (p < .05). Liposomal amphotericin B showed markedly higher peak plasma concentrations (approximately ninefold greater) and higher area under the plasma concentration curve values (approximately 14-fold higher) compared to conventional formulation. It is concluded that AmBisome® reached higher plasma concentration and lower distribution volume and had a longer half-life compared to Fungizone® , and therefore, AmBisome® is reported to be an appropriate and effective choice for the treatment of systemic mycotic infections in dogs.

Jugular venous emboli of brain tissue induced in sheep by the use of captive bolt guns.

Emboli of central nervous tissue were detected in the jugular venous blood of two of 15 sheep stunned with a conventional cartridge-operated captive bolt gun and in two of 15 sheep stunned with a pneumatically activated gun. No emboli were detected in arterial blood from these sheep or in venous blood from sheep stunned electrically. Emboli from an animal with BSE could transmit the disease to people.