Pharmacodynamics and pharmacokinetics of nalbuphine in xylazine­sedated horses.

This study describes the selected pharmacodynamics and pharmacokinetics of nalbuphine (NAL) in xylazine (XYL)­sedated horses. Five adult healthy horses were randomly received 2 treatments at a 1­week interval; XYL treatment (0.55 mg/kg IV) and XYL/NAL treatment (XYL, 0.55 mg/kg IV; NAL, 0.3 mg/kg IV). The measured pharmacodynamic variables were sedative and analgesic effects and the effect on ataxia and some physiological parameters. for the pharmacokinetics of NAL, its plasma concentrations were measured using HPLC and a 2­compartment analysis was performed. Greater and prolonged sedation was evident after XYL/NAL treatment compared with XYL treatment. Slightly improved and prolonged analgesia was demonstrated after XYL/NAL treatment. Significant changes in blood pressure and respiratory rate lasted for a shorter duration with XYL/NAL treatment than with XYL treatment. After XYL treatment, rectal temperature was significantly different from baseline and XYL/NAL treatment. Elimination half­life of NAL was 3.47 ± 1.39 hours and total body clearance was 2.88 ± 0.73 L/kg/hour. In conclusion, addition of NAL to XYL resulted in remarkable advantages on the measured parameters. The obtained pharmacokinetics of NAL could be useful in determining the effective NAL infusion rate, which could be further evaluated as an adjunctive agent to XYL for prolonged sedation in horses.

Virulence Determinants and Antimicrobial Profiles of Pasteurella multocida Isolated from Cattle and Humans in Egypt.

Pasteurella multocida is a Gram-negative bacterium that causes drastic infections in cattle and humans. In this study, 55 isolates were recovered from 115 nasal swabs from apparently healthy and diseased cattle and humans in Minufiya and Qalyubia, Egypt. These isolates were confirmed by kmt1 existence, and molecular classification of the capsular types showed that types B, D, and E represented 23/55 (41.8%), 21/55 (38.1%), and 11/55 (20.0%), respectively. The isolates were screened for five virulence genes with hgbA, hgbB, and ptfA detected in 28/55 (50.9%), 30/55 (54.5%), and 25/55 (45.5%), respectively. We detected 17 capsular and virulence gene combinations with a discriminatory power (DI) of 0.9286; the most prevalent profiles were dcbF type D and dcbF type D, hgbA, hgbB, and ptfA, which represented 8/55 (14.5%) each. These strains exhibited high ranges of multiple antimicrobial resistance indices; the lowest resistances were against chloramphenicol, ciprofloxacin, amoxicillin/clavulanic acid, and levofloxacin. The macrolide-lincosamide-streptogramin B methylase gene erm(Q), with erm(42) encoding MLSB monomethyltransferase, mph(E) encoding a macrolide efflux pump, and msr(E) encoding macrolide-inactivating phosphotransferase were present. The class 1 and 2 integrons and extended-spectrum ß-lactamase genes intl1, intl2, blaCTX-M, blaCTX-M-1, and blaTEM were detected. It is obvious to state that co-occurrence of resistance genes resulted in multiple drug-resistant phenotypes. The identified isolates were virulent, genetically diverse, and resistant to antimicrobials, highlighting the potential risk to livestock and humans.