Laboratory Animals最新文献

This study aimed to investigate the impact of selected analysis conditions on blood flow values and color maps in canine brain perfusion computed tomography (PCT) and to propose optimal analysis conditions. Dynamic computed tomography imaging was performed on six beagle dogs. Color maps were generated using a combination of analysis algorithms (box-modulation transfer function (Box-MTF) and singular value deconvolution plus (SVD+) methods), slice thicknesses (4.0 and 8.0 mm), analysis matrix sizes (512 × 512, 256 × 256, and 128 × 128), and noise reduction levels (strong and weak). Cerebral blood flow (CBF) and cerebral blood volume (CBV) were calculated for gray matter, white matter, basal ganglia, hippocampus, thalamus, and cerebellum in each map. CBF and CBV values obtained using SVD+ were significantly higher than those obtained using Box-MTF. Noise reduction was more effective with larger matrix sizes; however, excessive noise reduction led to the blurring of anatomical structures in the color map. Across all analysis algorithms, anatomical structures were challenging to visualize at 8.0 mm. For canine brain PCT, it is essential to choose a straightforward algorithm that remains unaffected by circulatory velocity or intracranial bone structure. Given the brain's size, the slice thickness should be minimal, noise reduction level should be suitable for the targeted area, and matrix size should be maximized.

In this study, we found that sevoflurane inhalation in rats prior to intraperitoneal injection decreased stress in both inexperienced experimenters and subject rats. Inexperienced experimenters anaesthetised male Sprague Dawley rats by intraperitoneal injection of anaesthetics, with or without preceding sevoflurane inhalation. Analysis using a visual analogue scale indicated that participating experimenters felt less stress when they performed intraperitoneal injections on rats after subjecting them to sevoflurane inhalation than when performing intraperitoneal injections alone. Plasma corticosterone concentrations of the anaesthetised subject rats were lower when the intraperitoneal injection was preceded by sevoflurane inhalation. Thus, our results demonstrated that it is advisable for inexperienced experimenters, until they gain confidence with experience, to perform sevoflurane inhalation on male rats before intraperitoneal injections.

The Institut Pasteur has set the ambition to encourage all staff to get involved in sustainable development across all departments on campus. The animal facility staff joined the efforts of the sustainable development department to analyse current and future processes and identify potential solutions and related brakes and leverages for the reduction of the animal facilities' environmental impact. The first step was to collect the managers' experience on the local initiatives. Then, the managers attended a workshop to share information on networks and initiatives relevant to the topic and community, and to discuss the use of consumables, including personal protective equipment, single use plastics, bedding, feed, water, chemicals, and waste management. On the topics of interest, local initiatives were specifically detailed to assess their eventual implementation in all the institute's animal facilities, and tasks were set to pursue the managers' efforts in the longer term. A scenario was used to teach how to compare the carbon footprints of washing and disinfection equipment and process and to decide on the design of an animal facility. Finally, a summary is drawn of the brakes and leverages for the reduction of the environmental impact of the institute's animal facilities.

When pain might occur during an animal experiment, sufficient analgesia is necessary. Metamizole is the third most used postoperative pain medication in animal research. The analgesic effect of metamizole is supposed to last 6-8 h in rodents. Therefore, the supplementation of drinking water with metamizole should be the preferred method to ensure permanent pain relief without unnecessary stressors. The present exploratory study compared the voluntary intake of metamizole-supplemented drinking water (3 mg/ml) between healthy mice of three different mouse strains. After the addition of metamizole to the drinking water, a marginal reduction in body weight was observed in C57BL/6J and BALB/c mice. However, NSG mice displayed a significantly higher body weight loss and reduction of drinking behavior compared with the C57BL/6J and BALB/c strains. The acceptance of metamizole in NSG mice did not increase with a different metamizole formulation. Thus, the mice of the inbred strains C57BL/6J and BALB/c seemed to be able to adapt to the taste of metamizole, while NSG mice were not able to accustom to analgesia within 1 week. Strain-specific habituation should be considered in future animal studies when analgesia is applied via drinking water.

Fish are increasingly used as experimental animals across research fields. Currently, around a quarter of all experimental animals used are fish. Less than 20% of these are standard model species. Welfare assessments for experimental fish are in their infancy compared with those for rodents. This can be attributed to the diversity of species used, the relative recency of fish as the go-to model for research, and challenges to assess welfare in non-vocal underwater species. The lack of guidelines and tools presents a challenge for researchers (particularly, for newcomers), for ethics committees and for implementing refinement measures. Here, we present an adaptable, user-friendly score sheet for fish based on MS Excel. The parameters are based on a literature review, have been validated by expert interviews and evaluated by a fish pathologist. The tool allows scoring of individual fish as well as groups, calculates summary scores and visualizes trends. We provide the underlying literature, give use examples and provide instructions on the adaptation and use of the score sheet. We hope that this tool will empower researchers to include welfare assessment in their routines, foster discussions on fish welfare parameters among scientists, facilitate interactions with ethics committees and, most importantly, enable the refinement of fish experiments.

Most animals used in experimentation are small mammals. In the EU, Directive 2010/63/EU regulates the use of laboratory animals for experimental purposes. However, there are few guidelines for the use of wild-sourced animals, which cover permits, experimentation, transport, maintenance, and setting free after experiments. To evaluate the effect of the Directive on the study of wild-sourced animals, we conducted a systematised literature review focusing on three widespread rodents of the genus Apodemus: Apodemus agrarius, A. flavicollis and A. sylvaticus. We selected studies performed across the EU, published before (2000-August 2010), during (September 2010-2012) and after implementation of the Directive (2013-2022). From those, we collected data on three main topics: i) authorisation; ii) care and accommodation and iii) methods of killing. We found that after implementation of the Directive a higher proportion of published studies provided information about authorisation. In contrast, there was no significant difference over time in the information given about the care and accommodation of animals or methods of killing. As such, our analysis suggests that there is still room for improvement to achieve consistency across journals publishing research involving wild-sourced small mammals. Specifically, editors should require the provision of detailed information by authors regarding proper animal care (e.g. more detailed care and accommodation protocols). To harmonise the information requested by different editorial boards, we recommend the addition of specific guidelines in the Directive regarding wild animals, particularly on their proper accommodation, manipulation, enrichment and veterinary control.

Increasing use of pigs as models in translational research, and growing focus on animal welfare are leading to better use of effective analgesics and anaesthetics when painful procedures are performed. However, there is a gap in basic knowledge such as pharmacokinetics of different anaesthetics in these species. The main objective of our study was to determine the pharmacokinetics of levobupivacaine in domestic pigs. Twelve female grower pigs weighing 31.17 ± 4.6 kg were subjected to general anaesthesia and experimental surgery, at the end of which they received 1 mg/kg levobupivacaine via peri-incisional subcutaneous infiltration. Plasma samples were collected before administration of levobupivacaine and at 0.5, 1, 2, 4, 8, 12, 24 and 48 h thereafter. Concentrations of levobupivacaine were determined by liquid chromatography coupled with tandem mass spectrometry. Following single dose of levobupivacaine, all animals had measurable plasma concentrations 0.5 h after drug administration, with most peak concentrations observed at the 1-h time point. In all 12 animals, levobupivacaine was below the limit of quantification 48 h after drug administration. The mean maximum plasma concentration, area under the curve and half-life were determined to be 809.98 μg/l, 6552.46 μg/l h and 6.25 h, respectively. Plasma clearance, volume of distribution and weight-normalized volume of distribution were 4.41 l/h, 35.57 l and 1.23 l/kg, respectively. Peak plasma concentrations in our study were well below concentrations that were found to produce toxicity in pigs.

The rat is one of the most employed animal models in biomedicine. Traditionally, weight gain has been utilized to gauge development and compare across species. Numerous studies have conducted longitudinal analyses of rat development, with emphasis on weight gain analysis. Given the high variability in these patterns, experimental data from a single laboratory may not be reliable for generalized estimation. This study aimed to analyze the effect of different factors on the pattern of weight gain during rat development. A literature survey was conducted to compile a database comprising nearly 300 data points of age and weight from 15 longitudinal studies. The database comprised both pre- and postnatal data. Utilizing the Gompertz equation, the data was analyzed to formulate a comprehensive model describing rat development. Differences in growth patterns became increasingly evident at later developmental stages, when significant differences in the maximum asymptote between sexes and strains were reached.