动物全身麻醉剂——846麻醉合剂的组合研究

选用高效镇痛药双氢埃托啡(DHM_(99)),强镇静、安定和肌松药保定宁、氟哌啶醇,进行了动物麻醉合剂的组合研究。通过正交试验筛选出最优组合为每毫升合保定宁60mg、DHM_(99)4μg和氟哌啶醇2.5mg(暂称为846麻醉合剂),其镇痛、镇静和肌肉松弛作用均显著地优于其他组合合剂。此合剂与单剂量的效应关系属于明显增强作用,既减少了各单药剂量,又降低了各单药的毒副反应,增大了安全性。     

A computed tomography–based method for the assessment of canine retrobulbar cone volume for ophthalmic anaesthesia

ObjectiveTo develop a comprehensive formula for calculating the volume of local anaesthetic solution used for retrobulbar anaesthesia in dogs with different skull morphologies.Study designRetrospective cohort imaging study.AnimalsSkull computed tomography (CT) images of 188 dogs of different breeds collected between January 2009 and December 2017.MethodsAnatomical integrity of the orbit and adjacent structures, presenting complaint, clinical signs and CT findings were verified to exclude ocular abnormalities. The volume of the retrobulbar cone of 376 eyes was calculated using CT scans of the dogs’ skulls. Additional data recorded included morphology of the skull, body weight, sex and size of the dogs, all of which were matched for possible association to the retrobulbar cone volume through univariable and multivariable linear regression models. Results of linear regression models were expressed as estimated beta coefficients with the corresponding 95% confidence intervals (95% CIs).ResultsUsing univariate analysis, the retrobulbar cone volume was positively associated with weight and male sex. In addition, brachycephalic and dolichocephalic dogs showed a larger retrobulbar cone volume than mesocephalic dogs, while sex was no longer significantly associated with the retrobulbar cone volume. In multivariate analysis, when considering all variables in the model, weight emerged as the strongest predictor (beta coefficient: 0.062 mL kg^–1, 95% CI: 0.056–0.067 mL kg^–1, p < 0.001).Conclusionsand clinical relevance In the veterinary literature, there is no agreement on the precise volume of local anaesthetic solution that should be used to achieve intraconal retrobulbar anaesthesia in dogs. Here we suggest a formula to calculate the retrobulbar cone volume and, accordingly, the injection volume of local anaesthetic solution for effective retrobulbar anaesthesia.     

兽用可注射缓释制剂研究进展

综述了兽用可注射缓释制剂的产生与发展、剂型特点及工艺设计等概况,并阐述了可注射缓释制剂近年来在国内外的研究开发情况,分析了研究过程中亟待解决的问题,并对其发展前景和推广应用进行了展望。     

Effects of repeated handling, with or without anaesthesia, on feed intake and growth in juvenile rainbow trout, Oncorhynchus mykiss (Walbaum)

The effects of weekly anaesthetization with clove oil and tricaine methanesulphonate (MS‐222) on feed intake and growth were examined in juvenile rainbow trout, Oncorhynchus mykiss (Walbaum), held individually. Repeated handling without anaesthetics significantly reduced feed intake and weight gain compared with an unhandled control group during an 8‐week experiment. When anaesthetics were used during handling the feed consumption and weight gain were significantly (MS‐222) or not significantly (clove oil) higher than in fish handled without anaesthesia. When compared with the unhandled control group, neither of these two anaesthetics had significant effects on feed intake but, in contrast to MS‐222, repeated anaesthesia with clove oil had a significant negative effect on growth. However, the effects of MS‐222 and clove oil on the growth were not significantly different from each other. Feed conversion ratio (feed/gain) of MS‐222‐anaesthetized fish was significantly higher compared with unhandled control and handled control fish but was not significantly different from fish anaesthetized with clove oil. These results suggest that both MS‐222 and clove oil alleviate handling stress in juvenile rainbow trout, and that these two anaesthetics are rather similar with respect to their effects during repeated exposures.     

Comparative efficacy of MS-222 and benzocaine as anaesthetics under simulated transport conditions of a tropical ornamental fish Puntius filamentosus (Valenciennes)

There is a growing commercial interest in the fish, Puntius filamentosus , in the ornamental fish trade in India and elsewhere. The trade is, however, hampered by severe mortalities during transport of the fish owing to insufficient data available on the use of anaesthetics. To resolve this problem, we evaluated the efficacy of two anaesthetics, MS-222 and benzocaine, in sedating P. filamentosus in simulated transportation experiments and used stress response parameters such as cortisol and blood glucose levels to perform assessments. We observed that MS-222 at 40 mg L⁻¹ and benzocaine at 20 mg L⁻¹ were sufficient to induce sedation for 48 h. Above these concentrations, both the anaesthetics adversely affected the fish and resulted in mortalities. Both anaesthetics significantly lowered the blood cortisol and glucose levels compared with the unsedated controls. Importantly, the anaesthetics treatment significantly lowered the post-transport mortality in the fish. The results of the study show that MS-222 and benzocaine could be used as sedatives to alleviate transport-related stress in P. filamentosus to improve their post-transport survival and hence reduce economic loss.     

Hypnotic effects and pharmacokinetics of a single bolus dose of propofol in Japanese macaques (Macaca fuscata fuscata). [corrected

ObjectiveTo describe the hypnotic effects of a single bolus dose of propofol in Japanese macaques, and to develop a pharmacokinetic model.Study designProspective experimental trial.AnimalsFour male macaques (5-6 years old, 8.0-11.2 kg).MethodsThe macaque was restrained and 8 mg kg^?1 of propofol was administrated intravenously at 6 mg kg^?1 minute^?1. Behavioural changes without stimuli (first experiment) then responses to external stimuli (the second experiment) were assessed every 2 minutes for 20 minutes. Venous blood samples were collected before and at 1, 5, 15, 30, 60, 120 and 210 minutes after drug administration, and plasma concentrations of propofol were measured (third experiment). Pharmacokinetic modelling was performed using NONMEM VI.ResultsMacaques were recumbent without voluntary movement for a mean 14.0 ± 2.7 SD (range 10.5-16.2) or 10.0 ± 3.4 (7.2-14.5) minutes and recovered to behave as pre-administration by 25.1 ± 3.6 (22.1-30.1) or 22.2 ± 1.5 (21.1-24.3) minutes after the end of propofol administration without or with stimuli, respectively. Respiratory and heart rates were stable throughout the experiments (28-68 breaths minute^?1 and 72-144 beats minute^?1, respectively). Our final pharmacokinetic model included three compartments and well described the plasma concentration of propofol. The population pharmacokinetic parameters were: V₁ = 10.4 L, V₂=8.38 L, V₃=72.7 L, CL₁= 0.442 L minute^?1, CL₂= 1.14 L minute^?1, CL₃= 0.313 L minute^?1, (the volumes of distribution and the clearances for the central, rapid and slow peripheral compartments, respectively).ConclusionsIntravenous administration of propofol (8 mg kg^?1) at 6 mg kg^?1 minute^?1 to Japanese macaques had a hypnotic effect lasting more than 7 minutes. A three-compartment model described propofol plasma concentrations over more than 3 hours.Clinical relevanceThe developed pharmacokinetic parameters may enable simulations of administration protocols to maintain adequate plasma concentration of propofol.