Evaluación de cuatro anestésicos en peces cebo de agua dulce (Cheirodon interruptus) (Ostariophysi: Characidae)

The aim of this study was to evaluate the response of eugenol, propofol, isoflurane and lidocaine on physiological and anaesthesiologic variables of Cheirodon interruptus, the most widely used baitfish in Argentina. Six groups were formed: 25 mg/l eugenol, 50 mg/l eugenol, 300 mg/l lidocaine, 0.2 mg/l isoflurane, 0.4 mg/l isoflurane, and 5 mg/l propofol. The tests are carried out with water at a temperature of 18.03±2.1 °C, pH 6.87±0.18, dissolved oxygen 6.73±0.05 mg l-1 and conductivity 3.74±0.04 μS cm-. The initial weight (1.6±0.4 g) and total length (5.1±0.4 cm) were statistically similar between groups. The results indicate that eugenol and isoflurane meet the requirements that a good anaesthetic for use in fish should meet. For propofol and lidocaine, it is considered necessary to review the dosage to adapt its use in C. interruptus due to the long recovery time. The fish treated with isoflurane (0.4 mg/l) and propofol had a significant decrease (p<0.001 and p<0.05, respectively) between baseline respiratory rate and during anesthesia. None of the drugs used caused fish deaths.El estudio tuvo como objetivo evaluar la respuesta del eugenol, propofol, isofluorano y lidocaína sobre variables fisiológicas y anestesiológicas de Cheirodon interruptus, el pez cebo de mayor utilización en Argentina. Se conformaron seis grupos: eugenol 25 mg/l, eugenol 50 mg/l, lidocaína 300 mg/l, isofluorano 0.2 mg/l, isofluorano 0.4 mg/l y propofol 5 mg/l. Los ensayos se realizaron con agua a temperatura de 18.03±2.1 °C, pH 6.87±0.18, oxígeno disuelto 6.73±0.05 mg l-1 y conductividad 3.74±0.04 μS cm-. El peso (1.6±0.4 g) y longitud total (5.1±0.4 cm) inicial fueron estadísticamente similares entre grupos. Los resultados indican que eugenol e isofluorano se ajustan a los requerimientos que debe reunir un buen anestésico para uso en peces. Para propofol y lidocaína se considera necesario revisar la dosificación para adecuar su uso en C. interruptus debido al elevado tiempo de recuperación. Los peces tratados con isoflurano (0.4 mg/l) y propofol tuvieron una disminución significativa (p<0.001 y p<0.05, respectivamente) entre la frecuencia respiratoria basal y durante la anestesia. Ninguno de los fármacos utilizados provocó muertes de peces

Pharmacokinetics and tissue disposition of enrofloxacin in rainbow trout after different routes of administration

Plasma pharmacokinetics (PK) and tissue disposition of enrofloxacin (EFX) was studied in rainbow trout (Oncorhynchus mykiss) after a single oral administration of 10 mg/kg, and by immersion baths of 20 ppm during 2.5 h and 100 ppm during 0.5 h, at water temperature of 16.3 ± 0.3 °C. Concentrations of EFX in plasma and tissues (skin, muscle, liver, kidney and gut) were determined using high performance liquid chromatography (HPLC) with fluorescence detection. Pharmacokinetic parameters were analyzed with a non-compartmental model. After oral administration, t½β, AUC and AUCtissues/AUCplasma ratio were 42.98 h, 21.80μg-h/ml and ≤ 18.63, respectively. After immersion baths of 20 ppm during 2.5 h and 100 ppm during 0.5 h, the t½β, AUC and AUCtissues/AUCplasma were 42.77 and 44.67, 9.83 and 12.83 μg-h/ml and ≤ 9.81 and ≤ 7.13, respectively. Therefore, oral (10 mg/kg) and bath administration in rainbow trout can provide AUC/MIC of ≥125 and Cmax/MIC of ≥10 to treat diseases caused by susceptible bacteria with MIC ≤ 0.04 μg/ml. This information can be helpful for the right use of EFX in rainbow trout. Also, this is the first study that determines the antibiotic tissue disposition in rainbow trout by using different administration routes.Fil: Urzúa Pizarro, Natala Francisca. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Clinica Animal. Área de Cirugía Experimental.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Messina, María Jimena. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Prieto, Guillermo Fermín. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Lüders, Carlos. Universidad Católica de Temuco; ChileFil: Errecalde, Carlos. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentin

Farmacocinética plasmática e urinária de marbofloxacina intramuscular em caninos

Plasma and urinary disposition of marbofloxacin was studied in canines (n = 6) after intramuscular administration of 2 mg/kg. At different times post-administration, blood samples were collected until 24 h, and urine samples, only from male dogs (n = 4) at 4; 8; 12, and 24 h. Liquid-liquid extraction of analyte with water, methanol, and centrifugation at 13500 rpm at 4 °C were performed. Separation and quantification were made using HPLC by reverse phase isocratic elution with a C18 column, fluorescence detector at 295 nm excitation and 490 nm emission, and a mobile phase consisting of water, acetonitrile, and triethylamine. Temporary plasma concentrations were analyzed with non-compartmental PK Solution 2.0 software. The results obtained indicate rapid absorption, as well as rapid and wide distribution. Cl and values of t½β and MRT indicate slow clearance and prolonged stay. The study evidenced plasma concentrations up to 24 h, which exceed the MIC of relevant pathogens. The AUC/MIC ratio indicates efficacy against microorganisms with MIC ≤ 0.15 μg/ml. Urinary levels of marbofloxacin are more significant than plasmatic levels. However, new studies are required to assess their use with the tested dose and route of application.Se estudió la disposición plasmática y urinaria de marbofloxacina en caninos (n = 6) tras la aplicación intramuscular de 2 mg/kg. En distintos tiempos posadministración se tomaron muestras de sangre hasta las 24 h, y de orina solo en los caninos machos (n = 4) a las 4, 8, 12 y 24 h. Se realizó una extracción líquido-líquido del analito con agua, metanol y centrifugado a 13.500 r. p. m. a 4 °C. La separación y cuantificación se realizó por HPLC mediante la elusión isocrática en fase reversa, utilizando columna C-18, detector de fluorescencia a 295 nm de excitación y 490 nm de emisión y fase móvil compuesta por agua, acetonitrilo y trietilamina. Las concentraciones plasmáticas temporales se analizaron con el software no compartimental PK Solution 2.0. Los resultados conseguidos indican pronta absorción, rápida y amplia distribución. El Cl y los valores conseguidos de t½β y TMR indican lenta depuración y prolongada permanencia. El ensayo determinó concentraciones plasmáticas perdurables hasta 24 h, y que exceden la CMI de patógenos relevantes. El cociente ABC/CMI indica eficacia frente a microorganismos con CMI ≤ 0,15 μg/ml. Las concentraciones urinarias de marbofloxacina son más significativas que las plasmáticas. No obstante, se requieren nuevos estudios que avalen su empleo con la dosis y vía de aplicación ensayada.Se estudou a disposição plasmática e urinária de marbofloxacina em caninos (n = 6) após a aplicação intramuscular de 2 mg/kg. Em diferentes tempos pós-administração se tomaram amostras de sangue hasta as 24 h, e de urina somente nos caninos machos (n = 4) a as 4; 8; 12 e 24 h. Se realizou uma extração líquido-líquido do analito com água, metanol e centrifugado a 13500 r. p. m. a 4 °C. A separação e quantificação se realizou por HPLC mediante a eluição isocrática em fase reversa, utilizando coluna C-18, detector de fluorescência a 295 nm de excitação e 490 nm de emissão e fase móvel composta por água, acetonitrilo e trietilamina. As concentrações plasmáticas temporárias se analisaram com o software não compartimental PK Solution 2.0. Os resultados conseguidos indicam pronta absorção, rápida e ampla distribuição. O Cl e os valores conseguidos de t½β e TMR indicam lenta depuração e prolongada permanência. O ensaio determinou concentrações plasmáticas perduráveis hasta 24 h, e que excedem a CMI de patógenos relevantes. O cociente ABC/ CMI indica eficácia frente a micro-organismos com CMI ≤ 0,15 μg/ml. Os níveis urinários de marbofloxacina são mais significativos que os plasmáticos. Não obstante, se requerem novos estudos que avalizem seu uso com a dose e via de aplicação ensaiada

Farmacocinética plasmática y urinaria de marbofloxacina intramuscular en caninos

Plasma and urinary disposition of marbofloxacin was studied in canines (n = 6) after intramuscular administration of 2 mg/kg. At different times post-administration, blood samples were collected until 24 h, and urine samples, only from male dogs (n = 4) at 4; 8; 12, and 24 h. Liquid-liquid extraction of analyte with water, methanol, and centrifugation at 13500 rpm at 4 °C were performed. Separation and quantification were made using HPLC by reverse phase isocratic elution with a C18 column, fluorescence detector at 295 nm excitation and 490 nm emission, and a mobile phase consisting of water, acetonitrile, and triethylamine. Temporary plasma concentrations were analyzed with non-compartmental PK Solution 2.0 software. The results obtained indicate rapid absorption, as well as rapid and wide distribution. Cl and values of t½β and MRT indicate slow clearance and prolonged stay. The study evidenced plasma concentrations up to 24 h, which exceed the MIC of relevant pathogens. The AUC/MIC ratio indicates efficacy against microorganisms with MIC ≤ 0.15 μg/ml. Urinary levels of marbofloxacin are more significant than plasmatic levels. However, new studies are required to assess their use with the tested dose and route of application.Se estudou a disposição plasmática e urinária de marbofloxacina em caninos (n = 6) após a aplicação intramuscular de 2 mg/kg. Em diferentes tempos pós-administração se tomaram amostras de sangue hasta as 24 h, e de urina somente nos caninos machos (n = 4) a as 4; 8; 12 e 24 h. Se realizou uma extração líquido-líquido do analito com água, metanol e centrifugado a 13500 r. p. m. a 4 °C. A separação e quantificação se realizou por HPLC mediante a eluição isocrática em fase reversa, utilizando coluna C-18, detector de fluorescência a 295 nm de excitação e 490 nm de emissão e fase móvel composta por água, acetonitrilo e trietilamina. As concentrações plasmáticas temporárias se analisaram com o software não compartimental PK Solution 2.0. Os resultados conseguidos indicam pronta absorção, rápida e ampla distribuição. O Cl e os valores conseguidos de t½β e TMR indicam lenta depuração e prolongada permanência. O ensaio determinou concentrações plasmáticas perduráveis hasta 24 h, e que excedem a CMI de patógenos relevantes. O cociente ABC/ CMI indica eficácia frente a micro-organismos com CMI ≤ 0,15 μg/ml. Os níveis urinários de marbofloxacina são mais significativos que os plasmáticos. Não obstante, se requerem novos estudos que avalizem seu uso com a dose e via de aplicação ensaiada.Se estudió la disposición plasmática y urinaria de marbofloxacina en caninos (n = 6) tras la aplicación intramuscular de 2 mg/kg. En distintos tiempos posadministración se tomaron muestras de sangre hasta las 24 h, y de orina solo en los caninos machos (n = 4) a las 4, 8, 12 y 24 h. Se realizó una extracción líquido-líquido del analito con agua, metanol y centrifugado a 13.500 r. p. m. a 4 °C. La separación y cuantificación se realizó por HPLC mediante la elusión isocrática en fase reversa, utilizando columna C-18, detector de fluorescencia a 295 nm de excitación y 490 nm de emisión y fase móvil compuesta por agua, acetonitrilo y trietilamina. Las concentraciones plasmáticas temporales se analizaron con el software no compartimental PK Solution 2.0. Los resultados conseguidos indican pronta absorción, rápida y amplia distribución. El Cl y los valores conseguidos de t½β y TMR indican lenta depuración y prolongada permanencia. El ensayo determinó concentraciones plasmáticas perdurables hasta 24 h, y que exceden la CMI de patógenos relevantes. El cociente ABC/CMI indica eficacia frente a microorganismos con CMI ≤ 0,15 μg/ml. Las concentraciones urinarias de marbofloxacina son más significativas que las plasmáticas. No obstante, se requieren nuevos estudios que avalen su empleo con la dosis y vía de aplicación ensayada

Pharmacokinetics of levofloxacin after single intravenous and oral administration, and its interaction with sucralfate in mixed-breed dogs

The study aims to establish the plasma pharmacokinetic parameters of levofloxacin in mixed-breed dogs, at a single dose of 5 mg/kg, intravenously, orally only and orally with sucralfate pre-treatment (1 g per animal), to evaluate its influence on antimicrobial absorption. Concentrations of levofloxacin in plasma were determined using high-performance liquid chromatography (HPLC) with fluorescence detection. After iv of levofloxacin, the mean (±SD) of AUC0–24, Vz, t½λz and MRT, was 19.05 ± 6.4 µg-h/ml, 2.43 ± 0.5 L/kg, 7.93 ± 1.41 hours and 8.7 ± 1.5 hours, respectively. After oral administration, the C max, t½λz and bioavailability were 1.95 ± 0.7 µg/ml, 7.65 ± 1.38 hours and 71.93 ± 9.75%, respectively. In animals given an oral dose of levofloxacin with sucralfate pre-treatment, there was a significant decrease (p < 0.05) in C max (0.57 ± 0.23 µg/ml), AUC (5.73 ± 2.26 µg-h/ml) and bioavailability (31.92 ± 14.19%). In the dogs studied, it is suggested that the dose 5 mg/kg of levofloxacin for both routes is inadequate to meet PK–PD targets for susceptible bacteria using breakpoints established by the Institute of Clinical and Laboratory Standards (CLSI).Fil: Urzúa Pizarro, Natala Francisca. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Clinica Animal. Área de Cirugía Experimental.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Messina, María Jimena. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Clinica Animal. Área de Cirugía Experimental.; ArgentinaFil: Caverzan, Matias Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Prieto, Guillermo Fermín. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Clinica Animal. Área de Cirugía Experimental.; ArgentinaFil: Lüders, Carlos. Universidad Católica de Temuco; ChileFil: Errecalde, Carlos. Universidad Nacional de Rio Cuarto. Facultad de Agronomia y Veterinaria. Departamento de Clinica Animal. Área de Cirugía Experimental.; Argentin

Anaesthetic effect of propofol on Rainbow Trout (Oncorhynchus Mykiss) in two different concentrations

The study aims to determine efficacy of propofol as an inmersión agent to induce anesthesia in rainbow trout(Oncorhynchus mykiss). Experimental study. Animals- 36 healthy rainbow trout Procedure- Trouts were sorted ramdomly in two groups, 18 fish each one. Both groups were anesthesized by bath, one of themwith 2,5 mg/l, the other one at 5 mg/l concentration. During the experiment, basal respiratory rate, partial and total equilibriumloss, time to anesthesia, anaesthesia respiratory rate and manipulation response were recorded. Induction and recovery times as well as behavioural response were recorded, being significantly affected by propofolconcentration (P <0.01). After exposure to 2,5 and 5 mg/l, fishes reached stage 3 anaesthesia in 4,99 ± 1,07 and 2,81 ± 0,71minutes respectively. Recovery time were 3,59 ± 1,44 for 2,5 mg/l and 7,49 ± 3,02 minutes for 5 mg/l. After the experiment, thefish remained for 48 hours in a pond attached to the unit, without any death. This study, showed the behavioural response ofrainbow trout to anaesthesia as well effectiveness of propofol as anaesthetic. Propofol induce safe dose dependent anaesthesia, being useful for different tasks related to the management of culture trout, as it meets the criteria established in aquaculture use. The results of the present work provide data to be used in surgical procedures andcontainment maneuvers in the different practices performed in fish farmingFil: Prieto, Guillermo. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Urzúa Pizarro, Natala Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Mancini, Miguel Alberto. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Tonini, María P.. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Messina, Jimena. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Salas, Sergio. Boca de Río Fish Farm; ArgentinaFil: Errecalde, Carlos. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentin