The study assessed the welfare of rabbits after inducing urethral stricture. This is a pilot study to assess appropriate experimental model before further experiments on the treatment of urethral stricture with artificial tissue. A review of the literature revealed that electrocauterization, also known as electrocoagulation, is the most reliable method for inducing urethral stricture in rabbits. The results were compared to the simple urethral incision, otherwise known as open urethrotomy. Unfortunately, we experienced that electrocauterization is poorly tolerated by laboratory animals. Weight loss was the most important parameter, indicated the poor health of the rabbit after surgery. In addition, we monitored other parameters such as temperature, fur quality, urination, general behavior, urine and blood samples. No major difference was found between the groups in any other parameter except for weight change. 4 weeks after the operation, the weight of the rabbits in the electrocauterization group had decreased by 12% compared to their initial weight. Electrocauterization group animals started to recover at the 5th postoperative week and returned to normal weight by the end of the 12th week. It is proven that postoperative conditions of the laboratory rabbits, like stress, discomfort during urination, pain or postoperative ileus could cause their weight loss. Open urethrotomy was tolerated better, the weight of rabbits in this group did not change notably, but urethral stricture did not develop either. In summary, we can conclude that electrocauterization is a reliable method of inducing urethral stricture, but in order to improve animal welfare, more intense analgesics and anti-inflammatory drugs should be administered. We suggest using an additional pain scale to monitor the welfare of rabbits, and continuing further experiments no earlier than 6-8 weeks after the initial urethral stricture induction, when the rabbits have recovered from the surgical intervention.
Rabbits as a species, are naturally overly sensitive to stress which is a source of concern and consideration for the use in research settings; both in terms of their interaction with humans, and in terms of the quality of the scientific outcome. To reduce stress and increase animal welfare, we have introduced an early rabbit/human habituation programme during the breeding and husbandry cycle; all the way from birth to when the rabbits are transported to the users. The programme consists in a holistic approach of early and positive human-rabbit bonding. It starts from birth with an imprinting phase of human contact in the nest boxes four times per week for 4 weeks. From weaning, the habituation programme continues with weekly positive interaction by individual petting outside the cage. The effect of the habituation programme was evaluated with several clinical stress indicators observed during the acclimatization period at the users. The study was designed as a double-blinded randomized protocol with rabbits being evaluated from four different breeding areas but with the habituation programme being implemented in one area only. After 16 months and with more than 2,400 rabbits evaluated, results showed a significant decrease in stress scores of rabbits being sourced from the area with the implemented habituation programme and with total disappearance of aggressive behaviours, such as biting, while initial stress scores were maintained for rabbits being sourced from the three other areas without the habituation programme.
We surgically implanted a 50 g PTT-100 (Platform Transmitter Terminal) in 21 Common Eiders (Somatria mollissima) and a 29 g PTT-100 in 10 Thick-billed Murres (Uria lomvia). After 2-4 months, one Common Eider implanted intracoelomically and two Thick-billed Murres implanted subcutaneously were harvested by local subsistence hunters and examined in the laboratory. External examination of the harvested birds did not reveal any morphological or pathological changes, while the surgical abdominal and cervical wounds seemed to have healed with granulation tissue in all three birds. Necropsy showed chronic inflammation and fatty necrosis in one of the murres, while the antenna Dacron cuffs were at skin level as originally attached for all three birds, with primary tissue healing and no signs of inflammation. In the eider, a few peritoneal adherences were found on the liver without additional signs of inflammation, while one murre had adherences and granulomatous tissue around the PTT with signs of severe inflammation and external rejection. These results indicate that birds can survive implantation of transmitters, even if inflammation develops around the implants. The study points to the importance of continuously refining the techniques for implanting devices in wild birds and performing necropsies on recovered birds.
Eosinophilia is a pathological condition characterized by an increased number of eosinophils in tissues and peripheral blood. The type 2 immune response causes eosinophilia, and interleukin-5 (IL-5) secreted by T helper 2 (Th2) cells is essential for increasing eosinophils. However, it is unclear whether there is another mechanism for an increase in eosinophils. The present study found high numbers of eosinophils in ICR mice and established an inbred strain with hypereosinophilia, named "Yama mouse", through brother-sister mating. Eosinophil count in the peripheral blood of 6-week-old Yama mice was 30-fold higher than in ICR mice of the same age, but hyperkeratisation of the stomach was the only lesion observed in Yama mice. There was no significant difference between ICR and Yama mice in IL-5 expression in the spleen, mesenteric lymph nodes or bone marrow. Yama mice revealed a mechanism for increased eosinophil counts other than that of IL-5 upregulation. Yama mice exhibit eosinophilia without artificial treatment; therefore, they are a good animal model for studying allergic diseases and regenerative medicine, in which eosinophils are important.
Gottingen minipigs, due to their low adult body weight, are frequently used for longitudinal imaging studies investigating disease progression or treatment effects. We recently showed that prolonged anesthesia, with intensive blood sampling and road transportation, affects internal organs in non-recovery positron emission tomography (PET) imaging studies in domestic pigs. In the current study, we examined if repeated non-invasive PET scans per se affect internal organs using computed tomography (CT). We then examined post-scan complications using clinical observations following PET imaging of Gottingen minipigs with (n=14) and without (n=4) invasive blood sampling. We report that non-invasive CT scans show no organ damage in minipigs (n=4) placed in sternal recumbence for PET scanning last-ing a few hours. Furthermore, upon reviewing medical records of other G & ouml;ttingen minipigs positioned in sternal recumbence during PET scans, two cases (5 % of scans) with minor post-scan complications were found during the first two weeks after scanning. Minipigs in dorsal recumbence with the surgical placement of femoral catheters for blood sampling were more frequently (6 cases, 43 % of scans) associ-ated with minor-to-moderate post-scan complications. A reduced daily gain in body weight was also observed after minipigs were placed in dorsal recumbence with blood sampling compared to pre-scan daily weight gain. The results suggest anesthetized Gottingen minipigs are somewhat affected by short-term PET scanning procedures, and blood sampling should be reduced when possible. Post-operative care should be improved due to the higher incidence of post-scan complications in minipigs with femo-ral artery catheterization.
Assessment of behavioural phenotype is crucial for the evaluation of various disease models, particularly in laboratory rodents. Traditionally, this includes performing a variety of conventional tests where animals are removed from their home-cages and placed in behavioural test apparatuses. This approach can be affected by micro-environmental stress (removal from cage, handling, moving to an unfamiliar setting, and the test itself) and other biases, by capturing animals’ responses in a short time-window and potentially missing subtle or circadian effects. Overall, serious concerns have been expressed regarding the validity and reliability of such measurements. To address some of these concerns, researchers are increasingly resorting to automated home-cage monitoring (HCM) technologies, which allow recording behavioural and physiological parameters of undisturbed animals continuously. In 2021, a pan-European network of researchers started the 4-year COST Action “Improving biomedical research by automated behaviour monitoring in the animal home-cage” (CA20135 TEATIME, https://www.cost-teatime.org/), where experts from different fields joined forces to critically assess the potential of available technologies, to develop guidelines and identify where further technological development is needed, including analysis of big data. The opportunities opened by home-cage monitoring for daily health and welfare monitoring of laboratory mice in a contactless, stress-free, and continuous fashion are also being duly explored. We provide a short overview of the progress made by the Action during the first year and a half (presentation available at https://osf.io/5dgz7).
This paper is a report of discussion, between responsible persons involved in animal research project evaluation throughout the Nordic region, on the activities, issues and problems encountered with evaluating project applications for experimental work involving the use of animals. Harmonization of the actions of responsible authorities in the evaluation of animal experimental projects is encouraged by policy makers at the European level, and the possibilities to encourage this are discussed. While the processes of evaluation and the composition of the committees are broadly similar across the region there are also differences. Applications are often made with insufficient attention, with sometimes too much non-essential information (for example details on molecular biology) given which tends to mask the important question of 'what is actually proposed to be done to the animals?'. Better guidance and simplification of the application process, in particular simplification of information required in the application document, may improve this. Lack of training was identified as a common problem, although to share best practice and flag common errors and problems.
Publishing the practical problems that occurred during a local or global disaster can help to plan improved future logistic and personnel management, and this can ultimately result in better welfare of laboratory animals. COVID-19 necessitated euthanasia of research animals, and partial or complete closure of laboratory animal facilities, throughout the world. In an attempt to find out the impact of COVID-19 lockdown on laboratory animals in India, a survey was conducted based on the voluntary participation of institutions from different regions of the country. A total of 56 facilities participated from 14 states and union territories. From their responses, 95% of the facilities continued their operations during lockdown. Among these facilities, 13% were completely operational. 63% had no interruption in receiving essential supplies and 16% operated with complete man-power. 20% paused breeding completely and 54% partially. In spite of the strict lockdown, 91% of the institutes were able to provide veterinary care. 60% of the institutions conducted online institutional animal ethical committee meetings indicative of continuing research activities. Many facilities reported animal morbidity (64%) and mortality (9%). To optimize resources 41% reported euthanasia of animals. Statistical analysis revealed a significant association of lockdown with increased animal morbidity, euthanasia and reduced animal breeding. In conclusion, even though lockdown had created a partial disruption of activities with some reduction in animal health and welfare, operations and research continued at most of the facilities surveyed in India.
We wished to improve the efficacy and safety of ketamine/xylazine anaesthesia in C57Bl/6JRj mice and achieve a surgical anaesthesia lasting 20-30 minutes, aiming at fewer anaesthesiarelated deaths and using the subcutaneous injection route to inflict less stress and pain on the mice. This was achieved by adding midazolam to the ketamine/xylazine anaesthetic solutions, at dosages of 193.55 mg/kg ketamine, 4.3 mg/kg xylazine and 3.76 mg/kg midazolam. This study demonstrated that subcutaneous administration of ketamine and xylazine in combination with midazolam resulted in surgical anaesthesia for at least 25 minutes. We also confirmed that a supplementary oxygen supply is necessary to maintain physiological levels of peripheral blood oxygenation in order to avoid hypoxia during ketamine/xylazine and ketamine/xylazine/ midazolam anaesthesia. As the current study was terminal, further research is needed to investigate correct dosages for recovery anaesthesia.
Pigs are common animal models in diabetes research. Streptozotocin-induced destruction of pancreatic beta-cells is used to induce diabetes in conscious pigs. However, in short-term non-recovery experiments, suppression of endogenous insulin secretion can be faster and more easily achieved with somatostatin analogues. We report a series of severe and unexpected episodes of severe bradycardia in eight pigs during non-recovery experiments with the original aim of investigating the pharmacokinetics and pharmacodynamics of intraperitoneal hormone delivery. The adverse events occurred four to five hours into the experiments, and we believe that they were caused by an interaction between the somatostatin analogue octreotide, and the sedative drug xylazine and that atropine delayed the time of occurrence.
Background: Parkinson’s disease (PD) is the most common neurodegenerative motor disorder and primarily affects movement control but also a range on non-motor functions. With unknown cause and lack of cure, much research is dedicated to find treatment. PD is characterized by progressive degeneration of midbrain dopamine neurons, primarily those of the substantia nigra pars compacta (SNc). Due to the complexity of the disease, animal models intended to represent symptoms similar to those observed in PD patients are instrumental to advance treatment prospects for PD. Among these, the 6-hydroxydopamine (6-OHDA) lesion model, in which dopaminergic neurons are chemically destroyed, is often favoured. However, while reproducing several features of clinical PD, including motor symptoms, mice exposed to 6-OHDA often suffer systemic dysfunction causing premature death. To avoid unnecessary spill of lives of laboratory mice and to increase the reliability of data obtained, there is a need for improved experimental protocols. Here we tested the effects of three parameters; lowered dose of toxin, careful post-operative care, and shortened interval between injection and sacrifice. Results: A detailed 6-OHDA lesion protocol using lower dose of toxin than commonly seen in the literature alongside careful post-operative care and decreased time post-injection resulted in high survival rate. Successful degeneration of midbrain dopamine neurons was confirmed in the SNc using several markers, and nigrostriatal projections were lost in the lesioned hemisphere. Dopamine neurons of the ventral tegmental area (VTA) were substantially affected as well. Conclusions: We demonstrate parameters that can be improved to increase well-being and survival of mice while preserving characteristic parkinsonian features in the 6-OHDA lesion model. A step-by-step protocol for implementation in any laboratory is provided.
Mice (Mus musculus) have a high basal rate of metabolism which increases during pregnancy and lactation. During peak lactation, water intake amounts to up to 65 % of the bodyweight per day. Providing water in a bottle may pose a restriction of water intake and lead to dehydration during periods of high demand, such as peak lactation. To establish if female mice are able to sustain a physiological hydration status during peak lactation, a completely randomized factorial design study was conducted with 12 RjOrl:SWISS (SWISS) and 12 C57BL/6JRj (B6) six-week old female mice in breeding. Female mice were randomly assigned to one of three groups with different watering alternatives: water bottle (Standard, n=6); water bottle + sachet with 98 % water gel (Gel, n=6); or water bottle + water bowl (Bowl, n=6). Non-mated females, provided with water bottles, served as controls (n=6). Hydration parameters [total protein (TP), hemoglobin, hematocrit, serum osmolality (Osmol), blood urea nitrogen (BUN)] and magnesium were measured in blood before mating (Pre) and during peak lactation (Peak), and at the same time points in controls. Water bottles were weighed during lactation and body weights of females and litters recorded at weaning. Data were analyzed by parametric or non-parametric methods to evaluate effects of strain, group and time point. The hydration parameters and magnesium were mostly within normal ranges in all animals at Pre and Peak. TP was lower at Peak in all lactating groups compared to Controls and to Pre (p<0.01). Mice in group Bowl consumed 54 % less bottle water compared with Gel and Standard (p<0.001), had 34 % lower levels of BUN than Standard and Control (p<0.01) and 5 % lower serum osmolality at Peak than Pre (p<0.01). Conclusion: Female mice are not dehydrated at peak lactation. However, they prefer to drink, and seemingly drink more water, from a bowl than from a bottle.
The aim of this study was to identify and assess the risk of spreading infectious agents in a colony of specific pathogen free (SPF) BALB/cOlaHsd mice when using non-sterile bedding and feed. The total number of microbial colonies in bedding was estimated, and their species identification was carried out using bacteriological methods. Infectious agents regulated for SPF mice were determined in the mouth and fecal swabs of mice using real time PCR. The mice in the animal facility were housed in individually ventilated cages (IVC). To assess the effect of air, one group of animals was kept in open-air cages (OAC). The study duration was 90 days. Staphylococcus epidermidis was identified in bedding in the groups of animals that were kept on non-sterilized bedding and in OAC. In addition, the level of bacterial contamination in the group with non-sterile bedding was significantly higher (1065 CFU/g) than the control group and higher than the other groups. These microorganisms in bedding were Lactobacillus spp, Staphylococcus spp and Escherichia coli. Staphylococcus spp and E.coli are not commensal microflora, but can be found in SPF animals. As a result of PCR testing, only Rodentibacter pneumotropicus was found in the mice; it was present in each group. It is assumed that the mouse colony was initially contaminated with this infectious agent. No visible pathological changes such as enlargement of the spleen, liver and lymph nodes, or intestinal distension, were detected at necropsy. The results of this study showed that personnel are possibly the main source of S. epidermidis because this microorganism is not found in SPF-mice. The transfer of bacterial agents occurs mainly through poor-quality bedding, as well as by the air.
Handling laboratory animals for husbandry and other procedures can be an important source of anxiety and stress, compromising animal welfare as well as the reliability of research that is sensitive to background stressors. Studies have revealed that picking up laboratory mice by the tail induces aversion, anxiety, physiological stress and depression-like behaviour, but such negative responses can be reduced substantially by using a handling tunnel that mice enter readily with minimal familiarisation. It has not been tested whether anxiety and aversion can be reduced similarly by using other objects to lift up mice from their home cage. Here we compared the willingness of C57BL/6NRj mice to interact voluntarily with their handler after being picked up either on a plastic ladder present in the home cage, or inside a familiar tunnel, or lifted by the base of the tail and then returned to the home cage. We also tested anxiety in open field and elevated plus maze tests once animals were familiarised with their assigned handling method. While mice picked up briefly by the tail were unwilling to interact with the hand that picked them up, mice picked up by ladder or tunnel readily approached, climbed on or entered these devices, with no significant difference in time spent with ladder or tunnel. Anxiety in an unfamiliar open field was reduced to a similar extent in ladder and tunnel handled mice compared with those picked up by the tail. Mice handled by tunnel also showed reduced anxiety in an elevated plus maze compared to those handled by tail, while ladder handling resulted in an intermediate response. Our study shows that, like tunnels, using home cage ladders to pick up mice reduces anxiety and avoids the aversion that is induced by picking up mice by their tails. We discuss the potential practicality of using ladders and tunnels to handle mice in different contexts.
Cloned animals are used in a wide range of species and in many contexts, such as agriculture, pharmaceutical production and animal research. Owing to their many benefits to humans, we can expect that the use of cloned animals will increase. Nevertheless, there is little focus on the ethical problems that are specific to the use of cloned animals among researchers and animal welfare bodies, as well as a lack of engagement with the general public on the subject. Most animal welfare problems that are specific for cloned animals may be ameliorated with improved husbandry methods. However, the discussion of the morality of using cloned animals will remain. This article gives examples of the ethical and welfare problems that are specific for the use of cloned animals compared to the use of conventional farm or research animals, and furthermore discusses the disconnect in the scientific community on their views on the use of cloned animals compared to the views in the general public.
Blood lactate is a parameter used for monitoring pigs during prolonged anaesthesia. Here we compared blood lactate and glucose concentrations in nine anaesthetised laboratory pigs. Seventeen of the samples originated from a liver project and 15 from a kidney project. Mean and standard deviations of arterial blood lactate and glucose were compared with values for portal, renal and femoral veins by using paired Student's t-test, paired Wilcoxon test as well as Spearman rank-order correlation. The study showed that lactate concentration was constant whether measured in blood from the femoral artery, portal vein, renal vein or femoral vein. The study showed that the origin of the blood sampled is not important and that changes in blood lactate concentration are likely to be the same throughout the cardiovascular system in healthy pigs.
Rodents are frequently used animal models in biomedical research. Catheterisation of a blood vessel in the tail is often performed to enable intravascular access for administration of drugs, fluid or blood sampling. Many experimenters employ a "Minasian tourniquet" to dilate the vasculature in the tail in order to ease catheterisation. Certain experiments, e.g. those that employ preclinical imaging techniques, require relatively long catheter-tubing (similar to 0.5 to 2 meters) to reach the rodent inside the scanner. Following catheter insertion, great care must be taken to carefully guide the loop of the tourniquet back along the entire length of the catheter. To minimise the risk of withdrawing the catheter accidentally during this step, a simple detachable tourniquet was created. This tourniquet can be removed completely and does not require careful guiding of the tourniquet-loop back along the catheter.
There is limited information on safe and effective neonatal rodent analgesia. The aim of this study was to evaluate the efficacy and duration of analgesia provided by buprenorphine (Bup) and lidocaine (Lid) in an incisional pain model. Male and female postnatal day three Sprague Dawley rat pups (n=40) were randomly assigned to one of five treatment groups: 1) Saline - 0.1 ml subcutaneous (SC)/0.01 ml saline incisional infiltration; 2) BupL - 0.025 mg/kg Bup, SC/0.01 ml saline infiltration; 3) BupH - 0.05 mg/kg Bup, SC/0.01 ml saline infiltration; 4) LidL - 2 mg/ kg lidocaine infiltration/0.1 ml saline SC; and 5) LidH - LDC 4 mg/kg lidocaine infiltration/0.1 ml saline SC. Rat pups were anesthetized with sevoflurane by mask, and a 1-cm full thickness skin incision was made over the left lateral thigh. Infiltration of lidocaine or saline occurred prior to wound closure with surgical glue. Baseline thermal latency was measured 24 hr prior to surgery, and subsequently 1, 2, 4, 8, 24, and 48-hrs post-operatively using an infrared diode laser. Thermal latency in the Saline group was significantly reduced compared to baseline up to the 4 hr timepoint. Both BupL and BupH attenuated thermal hypersensitivity for at least 4 hours in this model. LidL attenuated thermal hypersensitivity for 1 hr and LidH failed to attenuate thermal hypersensitivity. No abnormal clinical signs were noted for all treatment groups throughout the study. In summary, a single pre-operative dose of buprenorphine 0.025 to 0.05 mg/kg (SC) effectively attenuated postoperative thermal hypersensitivity in 3-day old neonatal rat incisional pain model for 4 hours.
This study describes the welfare and animals used for scientific and educational purposes in the field of laboratory animal sciences in Algeria. The aim of this study is to provide an overview of the status of the care and use of animals and to improve implementing plans and animal welfare measures. A literature review was performed using online databases and reference lists of the US National Library of Medicine to assess the prevalence of animal use for research in Algeria between 2013 and 2017. Also a retrospective study was conducted using the Pasteur Institute of Algeria report for 2015 to assess the prevalence of animal use in both teaching and research. The first workshop on animal experimentation was organized in 2013 in collaboration with international animal laboratory organizations (ICLAS and OIE) and involving the participation of universities, research centers, veterinary schools and the Pasteur Institute of Algeria. In addition, after accreditation of the Algerian Association of Experimental Animal Sciences, a number of training workshops and courses relating to laboratory animal sciences were organized. In Algeria the use of laboratory animals in research and education is a subject of debate regarding the need to establish regulations and to propose an appropriate ethical framework for the use of animals. Finally, some actions have been already taken in Algeria to promote the ethical use of animals but many more sustainable actions are needed and require cooperation, harmonization of policies and establishment of regional and international networks for experience exchange.
The naked mole rat (Heterocephalus glaber) is a rodent that has gained importance as a biomedical research model for various conditions including hypoxic brain injury, cancer and nociception. It is captured from the wild and housed under laboratory conditions during research. Much is unknown about how to optimize housing conditions for the animals in captivity. This study was designed to establish whether the animals will replicate in the laboratory their natural behaviour of having separate resting, waste disposal and eating areas. A total of 52 naked mole rats were kept in four colonies of different sizes and housed in two types of cage design. It was found that, in all four colonies, their behavior was similar to that in the wild with regards to separating their resting, eating, defecation and urination areas. Urination and defecation commonly occurred in the outer corners of the cages while resting and eating mostly occurred in the inner parts of the cages. Average daily feed consumption was 7.6 grams per naked mole rat. Weekly weight gain averaged 0.44 grams per naked mole rat. In this study, the four colonies of naked mole rats behaved similarly in their selection of resting, waste disposal and eating area. However, additional studies are needed to investigate further whether these behaviours can be affected by colony origin, colony size or cage size. The results of our study indicate that resting, eating and waste disposal behaviours need to be taken into consideration when housing naked mole rats, to optimize the comfort of these animals in captivity.
