Comparative Bioequivalence Study of Three Formulations of Enrofloxacin in Sheep

Abstract

A comparative pharmacokinetic study of three enrofloxacin injectable solutions was carried out in six healthy Barky rams after intramuscular injection according to a single dose, randomized, crossover experimental design. The three formulations were enrofloxacin 10% (Baytril(®)), enrofloxacin 10% plus bromhexine 1% (Mucotryl(®)) and enrofloxacin 10 % solution without bromhexine (Mucotryl without bromhexine). The three formulations were given a single intramuscular dose at a dose rate of 5 mg kg(-1) b.wt. The concentrations of the drug in the serum were measured using high-performance liquid chromatography (HPLC) with fluorescence detection. The results indicate that there were no significant differences between the distribution rate constant (k(ab)) and distribution half-life (t(1/2ab)), the maximum serum concentration (C(max)) and the time to peak concentration (T(max)) between Baytril and the other two formulations. There were significant differences between the elimination half life (t(1/2el)) and elimination rate constant (k(el)), for Baytril and enrofloxacin (the exact formulation of Mucotryl without bromhexine). Enrofloxacin was rapidly absorbed following IM administration of 5 mg kg(-1) b. wt. The peak serum concentrations (C(max)) were 2.83, 2.45 and 3.12 µg ml(-1) and were attained at (t(max)) 1.15, 1.41 and 1.26 hours when given Mucotryl, Baytril and enrofloxacin (the exact formulation of Mucotryl without bromhexine) to sheep, respectively. The injectable formulations investigated were bioequivalent after their intramuscular injection to sheep at recommended dose rate. As our results showed that, values of T(max), C(max) and AUC (Area under time curve concentration) determined for both Baytril, Mucotryl, and enrofloxacin (the exact formulation of Mucotryl without bromhexine ( reference ant test products) are within the acceptable range of 0.80-1.20, this means that the tested products product under investigation was bio-equivalent. These findings showed that the efficacy of the two test formulations was similar or possibly enhanced compared with Baytril based on the pharmacokinetic parameters obtained and due to concentration dependent activity of enrofloxacin.

Pharmacokinetics and tissue residue of enrofloxacin in healthy, Eimeria-infected broiler chickens and those pre-treated with amprolium and toltrazuril

“…Serum concentrations of enrofloxacin were measured by using HPLC according to the method described by El-Banna et.al. [24]. The HPLC system included: a TSP unit equipped with one pump; TST-P1000 unit equipped with a TSP-600LP UV-Vis variable lamp diode array and TSP fluorescent detector; an Altex-210A manual injector with 50 microlitre sample loop; and a Chromo-Quest computing integrator software.…”

Metabolism and residue differences of Enrofloxacin between the brain and peripheral tissues and the resulting brain damages in crucian carp (Carassius auratus var. Pengze)

“…Enrofloxacin (ENR), also known as ethyl Ciprofloxacin, is a synthetic third‐generation fluoroquinolone with a broad antibacterial spectrum (Attili et al, 2016; Polveiro et al, 2020). It is an animal‐specific antibiotic and then gradually used in aquatic organisms and livestock (Sheng et al, 2017), which is effective in the prevention and treatment against pathogenic microorganism infections triggered by both gram‐negative (G − ) and gram‐positive (G + ) bacteria (Fang et al, 2016), mycoplasmas (El‐Banna et al, 2011) and also mycobacteria (Küng et al, 1993). Due to its no cross‐resistance with other antimicrobial agents, ENR can be used in combination with other antimicrobial medicine to kill pathogenic microbes (Kumar et al, 2014).…”