Pub Date : 2024-08-01Epub Date: 2024-07-29DOI: 10.1177/00236772241246021
Giorgio Mattaliano, Natali Verdier, Moriz E Klonner, Michal Kyllar, Silvio Kau-Strebinger, Pablo E Otero
This prospective anatomical study aimed to establish an ultrasound-guided technique to the quadratus lumborum (QL) plane in sheep cadavers. Thirteen cadavers, weighing less than 117 kg, were included. In phase 1, one cadaver underwent dissection and two cadavers underwent 3D computed tomographic reconstruction for anatomical evaluation of the thoracolumbar region. In phase 2, two cadavers were used to compare two ultrasound techniques to the QL plane: lateral to the QL muscle with a transversal approach (LQL) and transmuscular between QL and psoas muscles with a longitudinal approach (TQL). For LQL, the reference was the first lumbar transverse process, whereas for TQL, it was the intertransverse region between the first and second lumbar vertebrae. The needle was advanced in-plane towards the specific target for each technique and a total of four injections were performed using 0.4 ml kg-1 of a dye-lidocaine solution. In phase 3, 10 cadavers received bilateral LQL injections (n = 20). All cadavers were then dissected to evaluate spread of dye. In phase 2, following LQL injections, no dye was observed in undesired locations; however, the dye was noted in the retroperitoneal space (1/2) after TQL injections. In phase 3, the 13th thoracic, first, second, third lumbar nerves, and sympathetic trunk segments were stained in 80%, 95%, 100%, 45% and 35% of the injections, respectively. In conclusion, the LQL technique was feasible, allowing staining of the spinal nerves innervating the cranial abdomen in sheep cadavers. Further studies in live animals are warranted.
{"title":"Ultrasound-guided quadratus lumborum block in sheep: A cadaveric study.","authors":"Giorgio Mattaliano, Natali Verdier, Moriz E Klonner, Michal Kyllar, Silvio Kau-Strebinger, Pablo E Otero","doi":"10.1177/00236772241246021","DOIUrl":"10.1177/00236772241246021","url":null,"abstract":"<p><p>This prospective anatomical study aimed to establish an ultrasound-guided technique to the quadratus lumborum (QL) plane in sheep cadavers. Thirteen cadavers, weighing less than 117 kg, were included. In phase 1, one cadaver underwent dissection and two cadavers underwent 3D computed tomographic reconstruction for anatomical evaluation of the thoracolumbar region. In phase 2, two cadavers were used to compare two ultrasound techniques to the QL plane: lateral to the QL muscle with a transversal approach (LQL) and transmuscular between QL and psoas muscles with a longitudinal approach (TQL). For LQL, the reference was the first lumbar transverse process, whereas for TQL, it was the intertransverse region between the first and second lumbar vertebrae. The needle was advanced in-plane towards the specific target for each technique and a total of four injections were performed using 0.4 ml kg<sup>-1</sup> of a dye-lidocaine solution. In phase 3, 10 cadavers received bilateral LQL injections (<i>n</i> = 20). All cadavers were then dissected to evaluate spread of dye. In phase 2, following LQL injections, no dye was observed in undesired locations; however, the dye was noted in the retroperitoneal space (1/2) after TQL injections. In phase 3, the 13th thoracic, first, second, third lumbar nerves, and sympathetic trunk segments were stained in 80%, 95%, 100%, 45% and 35% of the injections, respectively. In conclusion, the LQL technique was feasible, allowing staining of the spinal nerves innervating the cranial abdomen in sheep cadavers. Further studies in live animals are warranted.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"334-344"},"PeriodicalIF":1.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141792855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-01Epub Date: 2024-08-05DOI: 10.1177/00236772241242850
Heidi Morahan, Nicola Hancock, Lisa Bero, Kieron Rooney
While best practice methodology in animal research aims to address reproducibility and translational issues, awareness and implementation remains low. Preclinical systematic reviews have highlighted many flaws, including issues with internal validity and reporting. With early career researchers (ECRs) heavily involved in all aspects of animal experiments, it is crucial we understand what shapes their research practices. Semi-structured interviews were conducted with 13 ECRs, including research masters, PhD and postdoctoral academics. Data were collected and analysed concurrently using constant comparison techniques and an iterative approach. Findings revealed low-level awareness of best practice recommendations but a desire to engage in dedicated workshops on designing and reporting animal experiments. Current laboratory practices and previous literature were main influences on research practice, more than institutional training. An unexpected finding was the discovery of ethical and emotional dilemmas ECRs faced when working with animals. This highlights the need for a multifaceted approach to better support junior researchers, both emotionally and practically, to encourage responsible science.
{"title":"Experiences of early career researchers: Influences on the design and reporting of animal experiments, and the practical and emotional support needed to enhance best practice methods.","authors":"Heidi Morahan, Nicola Hancock, Lisa Bero, Kieron Rooney","doi":"10.1177/00236772241242850","DOIUrl":"10.1177/00236772241242850","url":null,"abstract":"<p><p>While best practice methodology in animal research aims to address reproducibility and translational issues, awareness and implementation remains low. Preclinical systematic reviews have highlighted many flaws, including issues with internal validity and reporting. With early career researchers (ECRs) heavily involved in all aspects of animal experiments, it is crucial we understand what shapes their research practices. Semi-structured interviews were conducted with 13 ECRs, including research masters, PhD and postdoctoral academics. Data were collected and analysed concurrently using constant comparison techniques and an iterative approach. Findings revealed low-level awareness of best practice recommendations but a desire to engage in dedicated workshops on designing and reporting animal experiments. Current laboratory practices and previous literature were main influences on research practice, more than institutional training. An unexpected finding was the discovery of ethical and emotional dilemmas ECRs faced when working with animals. This highlights the need for a multifaceted approach to better support junior researchers, both emotionally and practically, to encourage responsible science.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"354-364"},"PeriodicalIF":1.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141893766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-01Epub Date: 2024-07-29DOI: 10.1177/00236772241241561
Margarida N Pereira, Carlos Venâncio, Maria de Lurdes Pinto, Sofia Alves-Pimenta, Bruno Colaço
The intranasal route enables direct delivery of multiple substances from the nose to the brain, through olfactory and trigeminal pathways, bypassing the blood-brain barrier and avoiding systemic absorption. Despite the potential of this route, the various administration approaches make data reproducibility and interpretation challenging, emphasizing the necessity to establish a consistent methodology. Considering this, the aim of our study was to assess and compare the distribution of two dye volumes (30 µl and 50 µl) in the nasal cavity of rat cadavers. We employed three distinct methods of intranasal delivery: nose drops, by pipette tip, or cannula inserted into the nasal cavity. The results indicated that for both volumes, using the nose drops and the pipette tip methods, the dye dispersion occurred mainly in the vestibule, respiratory and olfactory regions, without reaching the olfactory bulbs. Using the cannula method, the deposition predominantly occurred in the respiratory and olfactory regions, with the dye reaching 66.7% and 100% of the olfactory bulbs, respectively, to low and high volume. Furthermore, the results demonstrated differences between the two volumes, in the pharynx, larynx, trachea, septal window, and incisive papilla, where an increased dye presence was observed with the 50 µl instillation across all three methods. According to our results, the intranasal delivery with a cannula was the most effective method for dye deposition in the olfactory region. However, further studies in live animals will be necessary to determine and refine the administration method that consistently allows specific deposition in the olfactory system.
{"title":"Refinement of intranasal delivery in rats: A cadaveric study.","authors":"Margarida N Pereira, Carlos Venâncio, Maria de Lurdes Pinto, Sofia Alves-Pimenta, Bruno Colaço","doi":"10.1177/00236772241241561","DOIUrl":"10.1177/00236772241241561","url":null,"abstract":"<p><p>The intranasal route enables direct delivery of multiple substances from the nose to the brain, through olfactory and trigeminal pathways, bypassing the blood-brain barrier and avoiding systemic absorption. Despite the potential of this route, the various administration approaches make data reproducibility and interpretation challenging, emphasizing the necessity to establish a consistent methodology. Considering this, the aim of our study was to assess and compare the distribution of two dye volumes (30 µl and 50 µl) in the nasal cavity of rat cadavers. We employed three distinct methods of intranasal delivery: nose drops, by pipette tip, or cannula inserted into the nasal cavity. The results indicated that for both volumes, using the nose drops and the pipette tip methods, the dye dispersion occurred mainly in the vestibule, respiratory and olfactory regions, without reaching the olfactory bulbs. Using the cannula method, the deposition predominantly occurred in the respiratory and olfactory regions, with the dye reaching 66.7% and 100% of the olfactory bulbs, respectively, to low and high volume. Furthermore, the results demonstrated differences between the two volumes, in the pharynx, larynx, trachea, septal window, and incisive papilla, where an increased dye presence was observed with the 50 µl instillation across all three methods. According to our results, the intranasal delivery with a cannula was the most effective method for dye deposition in the olfactory region. However, further studies in live animals will be necessary to determine and refine the administration method that consistently allows specific deposition in the olfactory system.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"324-333"},"PeriodicalIF":1.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141792854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-01Epub Date: 2024-07-25DOI: 10.1177/00236772231209198
Oddrun A Gudbrandsen
Male Zucker Diabetic Sprague Dawley rats were housed in standard individually ventilated cages with floor area of 1500 cm2, and were placed in a 'playcage' (a large open cage) for three visits per week from the age of 16-18 weeks. The playcage was introduced in an attempt to reverse the compulsive behaviour that the rats displayed in the individually ventilated cages, with the purpose to increase their well-being and to provide cognitive as well as physical stimulation. After two weeks of periodic stays in the playcage, the rats' repetitive behaviour in their home cage ceased, and the rats displayed signs of happiness and excitement when they were in the playcage. The observations strongly indicate that periodic stays in a larger playcage can be an alternative environmental enrichment for laboratory rats when housing in a larger home cage is not an option.
{"title":"Periodic stays in a 'playcage' as an environmental enrichment measure for laboratory rats housed in individually ventilated cages: Short report.","authors":"Oddrun A Gudbrandsen","doi":"10.1177/00236772231209198","DOIUrl":"10.1177/00236772231209198","url":null,"abstract":"<p><p>Male Zucker Diabetic Sprague Dawley rats were housed in standard individually ventilated cages with floor area of 1500 cm<sup>2</sup>, and were placed in a 'playcage' (a large open cage) for three visits per week from the age of 16-18 weeks. The playcage was introduced in an attempt to reverse the compulsive behaviour that the rats displayed in the individually ventilated cages, with the purpose to increase their well-being and to provide cognitive as well as physical stimulation. After two weeks of periodic stays in the playcage, the rats' repetitive behaviour in their home cage ceased, and the rats displayed signs of happiness and excitement when they were in the playcage. The observations strongly indicate that periodic stays in a larger playcage can be an alternative environmental enrichment for laboratory rats when housing in a larger home cage is not an option.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"365-368"},"PeriodicalIF":1.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141759586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Niemann-Pick disease type C (NPC) is a lethal genetic disease with mutations in NPC1 or NPC2 gene. Npc1-deficient (Npc1-/-) mice have been used as a model for NPC pathogenesis to develop novel therapies for NPC. However, Npc1-/- mice are infertile; thus, securing sufficient numbers for translational research is difficult. Hence, we attempted reproductive engineering techniques such as in vitro fertilization (IVF) and sperm cryopreservation. For the first time, we succeeded in producing fertilized oocytes via IVF using male and female Npc1-/- mice. Fertilized oocytes were also obtained via IVF using cryopreserved sperm from Npc1-/- mice. The obtained fertilized oocytes normally developed into live pups via embryo transfer, and they eventually exhibited NPC pathogenesis. These findings are useful for generating an efficient breeding system that overcomes the reproductive challenges of Npc1-/- mice and will contribute to developing novel therapeutic methods using NPC model mice.
C 型尼曼-皮克病(NPC)是一种致命的遗传病,NPC1 或 NPC2 基因会发生突变。Npc1缺陷(Npc1-/-)小鼠被用作NPC发病机制的模型,以开发治疗NPC的新型疗法。然而,Npc1-/-小鼠不能生育,因此很难获得足够的数量用于转化研究。因此,我们尝试了体外受精(IVF)和精子冷冻等生殖工程技术。我们首次成功地利用雄性和雌性 Npc1-/- 小鼠通过体外受精产生了受精卵细胞。我们还利用冷冻保存的 Npc1-/- 小鼠精子,通过体外受精获得了受精卵细胞。获得的受精卵细胞通过胚胎移植正常发育成活的幼崽,它们最终表现出鼻咽癌的发病机制。这些发现有助于建立一个高效的育种系统,克服Npc1-/-小鼠的生殖难题,并有助于利用鼻咽癌模型小鼠开发新的治疗方法。
{"title":"Efficient breeding system of infertile Niemann-Pick disease type C model mice by in vitro fertilization and embryo transfer.","authors":"Serina Kuroshima, Satohiro Nakao, Yuka Horikoshi, Kotono Ito, Akira Ishii, Aina Shirakawa, Yuki Kondo, Tetsumi Irie, Yoichi Ishitsuka, Naomi Nakagata, Toru Takeo","doi":"10.1177/00236772231194112","DOIUrl":"10.1177/00236772231194112","url":null,"abstract":"<p><p>Niemann-Pick disease type C (NPC) is a lethal genetic disease with mutations in <i>NPC1</i> or <i>NPC2</i> gene. <i>Npc1</i>-deficient (<i>Npc1</i><sup>-/-</sup>) mice have been used as a model for NPC pathogenesis to develop novel therapies for NPC. However, <i>Npc1</i><sup>-/-</sup> mice are infertile; thus, securing sufficient numbers for translational research is difficult. Hence, we attempted reproductive engineering techniques such as in vitro fertilization (IVF) and sperm cryopreservation. For the first time, we succeeded in producing fertilized oocytes via IVF using male and female <i>Npc1</i><sup>-/-</sup> mice. Fertilized oocytes were also obtained via IVF using cryopreserved sperm from <i>Npc1</i><sup>-/-</sup> mice. The obtained fertilized oocytes normally developed into live pups via embryo transfer, and they eventually exhibited NPC pathogenesis. These findings are useful for generating an efficient breeding system that overcomes the reproductive challenges of <i>Npc1</i><sup>-/-</sup> mice and will contribute to developing novel therapeutic methods using NPC model mice.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"313-323"},"PeriodicalIF":1.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141893732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-01Epub Date: 2024-08-05DOI: 10.1177/00236772231219292
Carlos Oscar S Sorzano, Irene Sánchez, Angel Naranjo
Regular health monitoring is crucial in laboratory animal facilities to determine the presence or absence of specific pathogens. One common approach to monitoring involves the use of sentinel animals, which are periodically exposed to biological material from the cages being monitored. At a certain point, some of these sentinel animals are tested for pathogens. This article discusses designing an effective sampling scheme to meet desired quality standards. It addresses questions such as the number of sentinel animals required, the frequency of sampling biological material, the selection of cages based on facility set-up, and the optimal frequency and quantity of sentinel animal tests. While existing design formulas are available for simple random sampling, no quantitative recommendation exists for using sentinel animals to the best of our knowledge. We propose a Monte Carlo simulation-based approach in this article to address this. Our algorithm has been implemented in a publicly accessible web page at http://nolan.cnb.csic.es/sentinelcagesmanager.
{"title":"Statistical design for health monitoring in laboratory animal facilities using sentinel animals.","authors":"Carlos Oscar S Sorzano, Irene Sánchez, Angel Naranjo","doi":"10.1177/00236772231219292","DOIUrl":"10.1177/00236772231219292","url":null,"abstract":"<p><p>Regular health monitoring is crucial in laboratory animal facilities to determine the presence or absence of specific pathogens. One common approach to monitoring involves the use of sentinel animals, which are periodically exposed to biological material from the cages being monitored. At a certain point, some of these sentinel animals are tested for pathogens. This article discusses designing an effective sampling scheme to meet desired quality standards. It addresses questions such as the number of sentinel animals required, the frequency of sampling biological material, the selection of cages based on facility set-up, and the optimal frequency and quantity of sentinel animal tests. While existing design formulas are available for simple random sampling, no quantitative recommendation exists for using sentinel animals to the best of our knowledge. We propose a Monte Carlo simulation-based approach in this article to address this. Our algorithm has been implemented in a publicly accessible web page at http://nolan.cnb.csic.es/sentinelcagesmanager.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"345-353"},"PeriodicalIF":1.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141893769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-03-18DOI: 10.1177/00236772231219821
Rafael Goterris-Cerisuelo, Sandra Sanahuja-Irene, María J Sánchez-Catalán, Fernando Martínez-García
For neonatal pups, parenteral anaesthesia is said to be not reliable as low doses induce no anaesthesia whereas high doses render high mortality rates. In this work we have adapted parenteral anaesthesia procedures approved for pups >7 days of age, to anaesthetize neonatal animals (postnatal days 3-4; P3-P4) for keeping them immobile for a long period. In our first experiment we analysed the behaviour of P3-P4 mouse pups for 70 min after intraperitoneal administration of low (37.5/3.75 mg/kg) or high (50/5) doses of a ketamine/xylazine anaesthetic mixture, both in the low range as compared with dosages employed in adults. Pups became immobile in ≈7 min and remained immobile for ≈45 min, irrespective of the age and dose of anaesthesia, younger pups (P3) being apparently more sensitive to the dosage. In the second experiment, we studied the response of P3 pups to mildly nociceptive stimulations, performed with a 4.0 g von Frey filament applied to the dorsal aspect of their paws. These stimuli elicited reaction in 100% of the cases in non-anaesthetized pups. The results indicate that the high dose significantly reduced responses as compared with the low dose of anaesthesia. With the low dose, <40% of the pups were unresponsive to nociceptive stimulation, whereas the high dose resulted in 50-60% of the animals not responding. Mortality was low irrespective of age or dose, suggesting that doses can be further increased if needed for invasive experimental procedures.
{"title":"Adjusting and validating a procedure for parenteral anaesthesia in neonatal mice.","authors":"Rafael Goterris-Cerisuelo, Sandra Sanahuja-Irene, María J Sánchez-Catalán, Fernando Martínez-García","doi":"10.1177/00236772231219821","DOIUrl":"10.1177/00236772231219821","url":null,"abstract":"<p><p>For neonatal pups, parenteral anaesthesia is said to be not reliable as low doses induce no anaesthesia whereas high doses render high mortality rates. In this work we have adapted parenteral anaesthesia procedures approved for pups >7 days of age, to anaesthetize neonatal animals (postnatal days 3-4; P3-P4) for keeping them immobile for a long period. In our first experiment we analysed the behaviour of P3-P4 mouse pups for 70 min after intraperitoneal administration of low (37.5/3.75 mg/kg) or high (50/5) doses of a ketamine/xylazine anaesthetic mixture, both in the low range as compared with dosages employed in adults. Pups became immobile in ≈7 min and remained immobile for ≈45 min, irrespective of the age and dose of anaesthesia, younger pups (P3) being apparently more sensitive to the dosage. In the second experiment, we studied the response of P3 pups to mildly nociceptive stimulations, performed with a 4.0 g von Frey filament applied to the dorsal aspect of their paws. These stimuli elicited reaction in 100% of the cases in non-anaesthetized pups. The results indicate that the high dose significantly reduced responses as compared with the low dose of anaesthesia. With the low dose, <40% of the pups were unresponsive to nociceptive stimulation, whereas the high dose resulted in 50-60% of the animals not responding. Mortality was low irrespective of age or dose, suggesting that doses can be further increased if needed for invasive experimental procedures.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"209-218"},"PeriodicalIF":1.3,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140143807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-01-31DOI: 10.1177/00236772231171191
Luciana Cintra, Sandra Regina Alexandre-Ribeiro, Julia Trindade Xavier Teixeira, Michel Mancinelli Megid, Thiago Vieira Coucolis, Dennis Albert Zanatto, Victoria Nathaly Leal, Silvia Maria Gomes Massironi, Claudia Madalena Cabrera Mori
The housing conditions of laboratory mice must be strictly controlled in order to reduce the impact of pathophysiological changes that affect animal health and welfare, possibly resulting in increased variability within experimental results. One way to improve the activity and survival of laboratory mice is to provide nesting material. The objective of this study was to determine if nest-building quality could be used to detect changes in murine mating behaviour in a rodent facility under controlled conditions. Nesting scores of 847 cages with monogamous pairs from three different genetic backgrounds (129, B6 and BALB/c) of both sexes were correlated with 18 predefined variables. The effects on nest quality were evaluated using descriptive data analysis, correspondence analysis and ordinal logistic model fitting. The results showed a strong relationship between nest quality and nest position. Humidity, genetic background, cage change and the number and age of pups in the cage affected the nest-building scores. The most important indicators were cage change and relative humidity, both of which exerted significant negative effects on nest-building quality. Even though the criteria were well defined, the observer could still influence nest score appraisal. However, in a long-term observational study, observers could improve their assessment by training and acquiring greater experience in score assignment. Nest-building scores are easy to assess in the cage, with little discomfort to the animal. Moreover, the nest score is a valid indicator of the health and well-being of laboratory mice and can provide valuable support in the management of animal facilities.
{"title":"Nest-building in breeding mice: Impact of macro- and micro-environment.","authors":"Luciana Cintra, Sandra Regina Alexandre-Ribeiro, Julia Trindade Xavier Teixeira, Michel Mancinelli Megid, Thiago Vieira Coucolis, Dennis Albert Zanatto, Victoria Nathaly Leal, Silvia Maria Gomes Massironi, Claudia Madalena Cabrera Mori","doi":"10.1177/00236772231171191","DOIUrl":"10.1177/00236772231171191","url":null,"abstract":"<p><p>The housing conditions of laboratory mice must be strictly controlled in order to reduce the impact of pathophysiological changes that affect animal health and welfare, possibly resulting in increased variability within experimental results. One way to improve the activity and survival of laboratory mice is to provide nesting material. The objective of this study was to determine if nest-building quality could be used to detect changes in murine mating behaviour in a rodent facility under controlled conditions. Nesting scores of 847 cages with monogamous pairs from three different genetic backgrounds (129, B6 and BALB/c) of both sexes were correlated with 18 predefined variables. The effects on nest quality were evaluated using descriptive data analysis, correspondence analysis and ordinal logistic model fitting. The results showed a strong relationship between nest quality and nest position. Humidity, genetic background, cage change and the number and age of pups in the cage affected the nest-building scores. The most important indicators were cage change and relative humidity, both of which exerted significant negative effects on nest-building quality. Even though the criteria were well defined, the observer could still influence nest score appraisal. However, in a long-term observational study, observers could improve their assessment by training and acquiring greater experience in score assignment. Nest-building scores are easy to assess in the cage, with little discomfort to the animal. Moreover, the nest score is a valid indicator of the health and well-being of laboratory mice and can provide valuable support in the management of animal facilities.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"219-230"},"PeriodicalIF":1.3,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139723200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-03-09DOI: 10.1177/00236772231209790
Juliana G da Silva, Juliana Pc Boechat, Bruno Dj Silva, Rodrigo Müller, José Pm Senna
Staphylococcus aureus nasal carriage is considered a risk factor for infections, and the development of nasal decolonization strategies is highly relevant. Despite they are not naturally colonized by Staphylococcus, mice are a good model for S. aureus nasal colonization. Murine models are easy to manipulate, and inter-laboratory reproducibility makes them suitable for nasal colonization studies. Strategies using bioluminescent bacteria allow for the monitoring of infection over time without the need to sacrifice animals for bacterial quantification. In this study, we evaluated S. aureus nasal colonization in three mouse strains (BALB/c, C57BL/6, and Swiss Webster) using a bioluminescent strain (SAP231). In vitro, a visible Bioluminescent Signal Emission (BLSE) was observed until 106 bacteria and detected by IVIS® imaging system up to 104 cells. Animals were inoculated with one or two doses of approximately 109 colony-forming units (CFU) of SAP231. Swiss Webster mice showed the longest colonization time, with some animals presenting BLSE for up to 140 h. In addition, BLSE was higher in this strain. BALB/c and C57BL/6 strains showed consistent BLSE results for 48 h. BLSE intensity was higher in Swiss Webster inoculated with both doses. Three different positions for image capture were evaluated, with better results for the lateral and ventrodorsal positions. After the loss of BLSE, bacterial quantification was performed, and Swiss Webster mice presented more bacteria in the nasal cavity (approximately 105 CFU) than the other strains. Our results demonstrate that bioluminescent S. aureus allow monitoring of nasal colonization and estimation of the bacterial burden present in live animals until 48 h.
{"title":"Monitoring <i>Staphylococcus aureus</i> nasal colonization murine model using a bioluminescent methicillin-resistant <i>S. aureus</i> (MRSA).","authors":"Juliana G da Silva, Juliana Pc Boechat, Bruno Dj Silva, Rodrigo Müller, José Pm Senna","doi":"10.1177/00236772231209790","DOIUrl":"10.1177/00236772231209790","url":null,"abstract":"<p><p><i>Staphylococcus aureus</i> nasal carriage is considered a risk factor for infections, and the development of nasal decolonization strategies is highly relevant. Despite they are not naturally colonized by <i>Staphylococcus</i>, mice are a good model for <i>S. aureus</i> nasal colonization. Murine models are easy to manipulate, and inter-laboratory reproducibility makes them suitable for nasal colonization studies. Strategies using bioluminescent bacteria allow for the monitoring of infection over time without the need to sacrifice animals for bacterial quantification. In this study, we evaluated <i>S. aureus</i> nasal colonization in three mouse strains (BALB/c, C57BL/6, and Swiss Webster) using a bioluminescent strain (SAP231). In vitro, a visible Bioluminescent Signal Emission (BLSE) was observed until 10<sup>6</sup> bacteria and detected by IVIS® imaging system up to 10<sup>4</sup> cells. Animals were inoculated with one or two doses of approximately 10<sup>9</sup> colony-forming units (CFU) of SAP231. Swiss Webster mice showed the longest colonization time, with some animals presenting BLSE for up to 140 h. In addition, BLSE was higher in this strain. BALB/c and C57BL/6 strains showed consistent BLSE results for 48 h. BLSE intensity was higher in Swiss Webster inoculated with both doses. Three different positions for image capture were evaluated, with better results for the lateral and ventrodorsal positions. After the loss of BLSE, bacterial quantification was performed, and Swiss Webster mice presented more bacteria in the nasal cavity (approximately 10<sup>5</sup> CFU) than the other strains. Our results demonstrate that bioluminescent <i>S. aureus</i> allow monitoring of nasal colonization and estimation of the bacterial burden present in live animals until 48 h.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"231-239"},"PeriodicalIF":1.3,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11264562/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140068534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-23DOI: 10.1177/00236772231163211
Joaquín Cogo Pagella, María F Rodríguez, Fabricio Frisina, Claudio O Cervino
Melatonin (ML) and dexmedetomidine (DM) are used separately as anesthetic premedication or as an anesthetic in humans and laboratory animals. In this study, we aimed to investigate the anesthetic properties of both drugs combined. The anesthetic effects of several combinations of ML (50 and 100 mg/kg) and DM (50 and 100 μg/kg) were evaluated in rats by observing behavioral manifestations and recording the duration and depth of anesthesia. Five anesthetic intervals were established according to the loss and recovery of reflexes. While each individual drug did not induce an appropriate anesthetic effect at the tested doses, ML50 + DM100, ML100 + DM50 and ML100 + DM100 combinations resulted in surgical anesthesia intervals of 60 to 360 min. Together, our results point that the use of ML allows to decrease the dose of DM, reducing the unwanted anesthetic effects of this α2-agonist.
{"title":"Combining melatonin with dexmedetomidine improves anesthesia in rats.","authors":"Joaquín Cogo Pagella, María F Rodríguez, Fabricio Frisina, Claudio O Cervino","doi":"10.1177/00236772231163211","DOIUrl":"10.1177/00236772231163211","url":null,"abstract":"<p><p>Melatonin (ML) and dexmedetomidine (DM) are used separately as anesthetic premedication or as an anesthetic in humans and laboratory animals. In this study, we aimed to investigate the anesthetic properties of both drugs combined. The anesthetic effects of several combinations of ML (50 and 100 mg/kg) and DM (50 and 100 μg/kg) were evaluated in rats by observing behavioral manifestations and recording the duration and depth of anesthesia. Five anesthetic intervals were established according to the loss and recovery of reflexes. While each individual drug did not induce an appropriate anesthetic effect at the tested doses, ML50 + DM100, ML100 + DM50 and ML100 + DM100 combinations resulted in surgical anesthesia intervals of 60 to 360 min. Together, our results point that the use of ML allows to decrease the dose of DM, reducing the unwanted anesthetic effects of this α<sub>2</sub>-agonist.</p>","PeriodicalId":18013,"journal":{"name":"Laboratory Animals","volume":" ","pages":"277-280"},"PeriodicalIF":1.3,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141081930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}