Albendazole is an anthelmintic drug commonly used in animals and humans against nematodes. A sensitive, accurate, precise, and time-saving high-performance liquid chromatography (HPLC) method for the simultaneous determination of albendazole and metabolites (albendazole sulfoxide and albendazole sulfone) in cattle plasma has been developed and validated. A solid-phase extraction (SPE) was carried out. Separation was performed with an XBridge^® C18 column (4.6 mm × 250 mm, 5 µm) with gradient elution of acetonitrile:ammonium acetate buffer 0.025 M with pH adjusted to 6.6. The flow rate was 1.2 mL/min, and the PDA detector was set at 292 nm. Calibration curves were linear in the range from 0.025 to 2.0 µg/mL for the three compounds evaluated, with correlation coefficients ≥ 0.99. For the lower limit of quantification (LLOQ), within- and between-run precision and accuracy were satisfactory, with coefficients of variation (CV) ≤ 15.1% and deviations ≤ 117.7%, respectively. The method fulfilled all validation criteria established by the European Medicines Agency guideline (EMA/CHMP/ICH/172948/2019).

Antimicrobial resistance is nowadays a global health issue, mainly related to antibiotic overuse and misuse in different sectors. In veterinary medicine, it is essential to understand farmers’ knowledge and awareness of this serious problem in order to minimize it. In Spain, there are virtually no studies on this issue. A cross-sectional online study was carried out among Spanish farmers to identify their knowledge and awareness of antibiotic use and antimicrobial resistance (AMR). Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated, and logistic regression analysis was also performed. 217 farmers took part in the study, and 215 surveys were analyzed. Farmers were mainly men (60%), middle-aged (76.8%), and with more than 15 years of professional experience (41.4%). They worked mostly in extensive systems of production (53.5%), usually with only one species (54%), with ruminants being found in most farms (70.2%). Most participants showed a satisfactory knowledge of this topic, a positive attitude towards reducing the use of antibiotics, and a growing awareness of their importance for public health, although for almost a fifth of them the meaning of AMR is unclear. Respondents were more likely to achieve satisfactory scores if they were between 31 and 45 years (OR = 2.42, p < 0.05) and rearing only ruminant species (OR = 2.51, p < 0.05). Spanish livestock farmers have an acceptable level of knowledge about antibiotics and AMR, although there are still gaps related to the adequate use of these drugs.

There is little information in veterinary literature on the perioperative pharmacological management of small animal patients, despite the existence of common protocols and the importance of properly managing this period to reduce anaesthesia-related detrimental effects. This study aimed to analyse the current use of perioperative drugs in companion animals treated at the Veterinary Teaching Hospital of the University of León (HVULE) in Spain over a period of 5 years (2018–2022), describe the prescription patterns of these medicines, and identify the main variables associated with their prescription to explore possible strategies to promote their appropriateness. A total of 3438 cases were included in this study. The animals that most frequently underwent surgery were dogs (58.2%), females (57.0%), and adults (73.0%). The primary procedures performed were reproductive (56.6%) and traumatological (19.8%) surgeries. Regarding pharmacological treatments, more than half (62.3%) belonged to the ATCvet classification QN group (nervous system), and the most common compounds were isoflurane (13.5%), methadone (13.5%), and propofol (12.7%). Amoxicillin/clavulanic acid (3.7%) and marbofloxacin (2.8%) (categories C and B in the European Medicines Agency categorisation, respectively) were the most prescribed antibiotics. These findings provide detailed data to help veterinary policymakers improve drug use during surgical procedures.

Background/Objectives: Gentamicin (GEN) is an aminoglycoside antibiotic used in veterinary medicine to treat infections caused mainly by Gram-negative bacteria. GEN is a mixture of pharmacologically active components, known as isoforms. The objective was to develop and validate a sensitive, accurate, and precise Ultra-Performance Liquid Chromatography with triple quadrupole mass detector (UPLC-MS/MS) method to quantify the different GEN isoforms in pig plasma and feces using streptomycin as an internal standard. Methods: Solid-phase extraction (SPE) was carried out. A high-strength silica (50 × 2.1 mm, 1.8 µm) column was used for chromatographic separation and a mobile phase of 0.26% HFBA in water (A) and acetonitrile (B) was delivered in a gradient with a flow rate of 0.5 mL/min. The column temperature was 40 °C and the sample injection volume was 30 µL. Results: The method showed good selectivity and specificity, with no interfering peaks. Calibration curves were linear in the range from 0.05 to 0.3 µg/mL for all isoforms in both matrices. Within- and between-run precision and accuracy were satisfactory for the lower limit of quantification (LLOQ), with coefficients of variation (CV) ≤ 13.4% and deviations ≤ 116.5% in plasma and CV ≤ 12.3% with deviations ≤ 101.7% in feces. No carry-over was observed, and analyte stability was confirmed under different storage conditions. Conclusions: The method development fulfilled all validation criteria established by the European Medicine Agency Guideline (EMA/CHMP/ICH/172948/2019). Moreover, the applicability of the method in clinical practice was demonstrated by the quantification of GEN in plasma and feces samples from pigs.

Optimizing the use of the existing anthelmintics has become a priority, as resistance is a growing concern worldwide and the development of novel antiparasitic drugs slow. The paper describes the pharmacokinetic interaction between the antiparasitic albendazole (ABZ) and the choleretic drug menbutone (MEN) in calves, when ABZ was administered orally (7.5 mg/kg) alone or with intramuscular MEN (10 mg/kg) (1 or 2 doses 24 h apart) to 12 animals. Blood samples were collected at 14 sampling points over 72 h, and plasma concentrations of ABZ, albendazole sulfoxide (ABZSO, active metabolite), and albendazole sulfone (ABZSO ₂ , inactive one) were measured using high performance liquid chromatography (HPLC). Pharmacokinetic parameters were calculated with non-compartmental methods. No ABZ was detected at any sampling time, whereas ABZSO was determined for longer than ABZSO ₂ . A significant increase in systemic exposure of ABZSO was observed following concomitant administration of MEN, with a mean ABZSO maximum plasma concentration (C _max ) and area under the plasma concentration-time curve (AUC) 33.5 and 31.8% higher, respectively, when a dose of MEN was administered. The second administration of MEN did not improve the amount absorbed compared with a single dose of the choleretic drug. As for ABZSO ₂ , C _max , AUC and t _max values were similar regardless the treatment followed (ABZ alone or with one or two doses of MEN). Thus, our results show that the simultaneous administration of ABZ with a single dose of MEN in cattle may increase the amount of ABZSO and maintain the efficacy of ABZ, whereas a second dose of MEN offers no such benefit.