Overdose of injectable barbiturates or barbituric acid derivatives is the most preferred euthanasia method for the majority of animal species. However, these controlled drugs have limited access, and in this case or in any other scientific concerns, veterinarians may choose alternative, conditional acceptable methods as recommended by American Veterinary Medical Association (AVMA) Guidelines for the Euthanasia of Animals. In the newest 2020 Edition, existing euthanasia methods, techniques and agents of euthanasia are updated according to recently released articles. This article summarized the updated content of the new version of the AVMA Guidelines and on this basis, enumerated the most preferred methods of euthanasia, methods acceptable with conditions and unacceptable methods to euthanize different animal species. In addition, principles and precautions related to animal euthanasia were also briefly described.

General anesthetics used for laboratory animals are mostly controlled drugs, and are subject to strict supervision by the competent government agency in China. Many general anesthetics recommended in the literature are either unavailable or difficult to procure/access in the market, resulting in limited options for clinical use. Furthermore, not all laboratory veterinarians have practical experience in species-specific anesthetic selection and use. Owing to these factors, general anesthesia presents a common institutional challenge in animal surgical programs and serves as a bottleneck that restricts the sustainable development of biomedical industries working with laboratory animal species. This article summarizes the pharmacological properties of common general anesthetics and provides suggestions for general anesthesia in different laboratory animal species.

China National Accreditation Service for Conformity Assessment (CNAS) laboratory animal institutions accreditation is an important system for the management of laboratory animals in China. It is a third-party evaluation on Chinese characteristics dedicated to ensuring the quality and welfare of laboratory animals in China. The American Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC) certification provides global services about animal welfare evaluation and ethical certification, which are important for management and use of laboratory animals. This study compared and analyzed the nature of CNAS and AAALAC, the nature of CNAS accreditation and AAALAC certification, the evaluation principles, required documents, the evaluation process, the management of reviewers, and the acceptance of results, and discussed the differences and characteristics of the two evaluation systems for laboratory animal institutions.

Objective To investigate the positive effects of four different forms of environmental enrichment on the welfare of mice subjected to restraint stress with the purpose of screening suitable enrichment. Method Mice undergoing poor welfare due to repeated restraint were kept in different enriched environment (enriched by march，serenade，blue filter or red filter), food consumption and body weight gain were recorded throughout the study. Two weeks later all the animals were assessed for their stress level by measuring physiological parameters (body weight, food efficiency ratio[FER], thymus index, spleen index and total leukocyte in peripheral blood[WBC]) and biochemical parameters (serum levels of ACTH，CORT，[3-EP，EPI，NE，IL-2，TP, GLU, TCHO). Result In restraint control group, restraint stress decreased their body weight gain, FER, WBC, IL-2, p-EP( P＜/i><0.01) and spleen index (P＜0.05)，while increased their ACTH,CORT, NE(P＜0.01) and EPI(P＜0.05). Compared to restraint mice, mice from blue light group and from serenade group exhibit lower levels of ACTH and NE(P＜0.01 )，as well as the restoration level of p-EP(P＜0.01) by blue light, indicating elevated neuroendocrine responses to restraint stress. With respect to the higher level of IL-2 (P＜0.01)，more WBC(P＜0.01) and larger thymus index(P＜0.01，compared to control group), blue light may contribute to relieve the inhibitory status in immune system induced by restraint. When comes to other groups, mice from red light group tended to eat more at daytime than at night compared to mice from restraint control group, and mice from march reduced their serum levels of CORT too much. Conclusion Enrichment with either serenade or blue filter partly enhanced resistance to repeated restraint stress in mice, thus suggest that both forms of enrichment should be beneficial for the welfare of laboratory mice. However, the effects of march and red light are debatable and need more investigation.

With the development of laboratory animal science in biomedical research, more and more people pay attention to the care and use of laboratory animals, especially animal welfare. There are several components in an effective animal care and use program，among which, adequate veterinary care is considered internationally to be one of the most essential components. Many countries and non-governmental organizations have promulgated guidelines for adequate veterinary medical care for laboratory animals. The objective of this article is to introduce western notions of veterinary care to Chinese audiences，to identify the gaps between China and other countries on this aspect and to recommend the possible resolutions.

Objective To investigate whether an acclimatization period should be introduced into the home cage experiment for the detection of metabolic function in mice, and how to judge and set its length. Methods Data from 31 home cage experiments in 2016-2017 were collected, and each experiment was set up with a 3-day (72 hours) acclimatization period. Data such as water consumption, food intake, heat production, and body weight were recorded. The data were analyzed using 24-hour interval analysis to determine the acclimatization effect. Results Approximately 12% of the 356 mice drank less than 1 mL at the end of 96 hours. There were significant differences in water consumption, food intake, heat production rate, and body weight between 24-48 hours and 48-72 hours, but no significant differences were detected between 48-72 hours and 72-96 hours, except in food intake. Independent verification of the food intake of each experiment showed that there was a significant correlation between food intake adaptability and weight. Conclusion Approximately 12% of the mice were unable to learn or adapt to the new water bottle after the 72-hour acclimatization period, therefore, researchers should consider increasing the sample size of the experiment to eliminate invalid data. If food intake is not the focus of a study, the 48-hour acclimatization is sufficient to obtain reliable results.

Objective To investigate the effect of environmental enrichment on alleviating stress in laboratory British-shorthair cats.Methods A total of fourteen laboratory British-shorthair cats were randomly divided into welfare group (n = 7) and control group (n = 7) according to the presence of environmental enrichment interventions which lasted for 11 weeks. The hematological and blood biochemical, neuroendocrine and immunological parameters of each group were measured and compared to evaluate the stress level of different groups.Results The mean corpuscular volume in the welfare group was significantly lower than that in the control group (P < 0.05), the percentage of lymphocyte was extremely higher than that in the control group (P < 0.01), and the neutrophilic percentage was extremely lower than that in the control group (P < 0.01). In addition, the levels of carbamide, creatinine, globulin, total protein in the welfare group were significantly lower than those in the control group (P < 0.05); the adrenaline and dopamine indicators in the welfare group were significantly lower than those in the control group (P < 0.05), while interferon-γ (IFN-γ), interleukin (IL)-1β, IL-2, IL-4, IL-5, IFN-γ/IL-4 ratio, IL-2/IL-4 ratio, IFN-γ/IL-5 ratio and IL-2/IL-5 ratio of the welfare group were higher than those of control group; among them, IFN-γ, IL-2, IFN-γ/IL-5 ratio and IL-2/IL-5 ratio were significantly different (P < 0.05), and IL-5 difference was extremely significant (P < 0.01).Conclusion The environmental enrichment interventions can effectively improve the welfare level of laboratory cats and reduce the biological costs of stress.

The welfare and ethics of laboratory animals in drug development has attracted increasing attention, and how to treat animals well has become an important topic. Blood microsampling overcomes several disadvantages of conventional large-volume blood sampling methods, such as complex operation, great harm to animals and high requirement on rodent quantity, and has great advantages in animal welfare, scientificity and cost. Therefore, its application is regarded as an important practice to implement the 3Rs. This article reviewed the latest research progress of blood microsampling, and its advantages and challenges in non-clinical studies in order to promote the wider application of this new technique in this field.

 Many policies, regulations and standards related to laboratory animals have been issued in China with more than 30 years of development. The understanding of the laboratory animal welfare has been deepened in researchers. The operation and management of the Welfare and Ethics Committee have become more and more standardized. The welfare of laboratory animals can be guaranteed with the high quality management of the Welfare and Ethics Committee. Based on the work experiences, searching the literature and peer exchange, the authors described the common problems found in the oversight and ethical review process, and proposed solutions for improving the experimental animal welfare.

The use of electrode implantation technology to explore the electrical activity of population neurons is crucial for brain and cognitive science, brain-like research and brain-computer interface technology research. This article introduces the nursing points and significance of electrode implantation in rhesus monkey cerebral cortex before, during and after operation. Preoperative care includes preoperative preparation, preoperative medication, cranial fixation, skin preparation, etc. Intraoperative care includes physiological index monitoring and cerebral cortex implantation surgery care, while postoperative care includes observation and monitoring, debridement and nutritional care. Doing a good job in the operation of electrode implantation into the cerebral cortex of rhesus monkeys can not only improve the success rate of the operation, use as few experimental animals as possible to obtain the data required for the experiment, but also reduce the pain and injury caused by the operation to the animals, which is of great significance for brain and cognitive science research and animal welfare protection.

The aim of reproductive and developmental toxicity study is to identify the effects of exogenous substances on reproductive function and development of mammals by animal experiments, predicting the potential adverse effects on reproductive cells, pregnancy, pregnancy, delivery, lactation and other parental reproductive functions, as well as on the development of offspring embryos/fetuses and postnatal development. The methods of studying the reproductive and developmental toxicity of whole animal in females have been widely used in the evaluation of reproductive and developmental toxicity of drugs, food, chemicals and cosmetics. However, its main problems are insensitivity, long cycle, and large sample size. Especially, as the reproductive function of in vivo experiments is mainly based on parameters related to reproductive and developmental consequences, it is difficult to reveal the toxic action site and mechanism. Alternative method of female reproductive and developmental toxicology refers to any method or procedure which can replace animal experiments whenever possible, reduce the required number of animals or optimize and reduce animal suffering in animal experimental program, especially in preliminary evaluation of exogenous toxic substances as a powerful complement for animal experiments. In this paper, the technique and research progress of in vitro culture of female reproductive developmental toxicity were summarized in this paper, the advances in vitro culture of female reproductive toxicity were summarized from cells and tissue culture in female reproductive system, embryonic cells and tissue culture, breast cell culture so as to provide references for the study of in vitro culture of reproductive and developmental toxicity in females.

The results of medical research are usually obtained by means of effective animal experiments, and at the expense of laboratory animals themselves being hurt or suffering. How to improve the welfare of laboratory animals on the premise of ensuring the scientific and reliable results of animal experiments is a problem that every medical researcher should consider. This paper, starting from the present situation of animal welfare in China's medical scientific research, points out the differences between China and the developed countries in Europe and the United States, and analyzes the reasons for the lagging of animal welfare in scientific research and experiment in China. In order to promote the rapid improvement of the welfare level of experimental animals in China, the measures of speeding up the standards and rules of the laboratory animal welfare technology, strengthening the publicity and education of experimental animal welfare and establishing a scientific animal welfare ethics review system are proposed.

Objective To observe the effects of chronic stress on animal welfare related indexes in rats. Methods Eight weeks old SPF SD rats were subjected with chronic stress by electric shock observing.Body weight gain and blood pressure of the rats were recorded throughout the experiment.The expressions of mRNA and protein of nuclear factor-κB (NF-κB) p65 in liver cells were measured by real-time quantitative PCR and immunohistochemical method respectively when the experiment ended.Interleukin-2 (IL-2),epinephrine (EPI),norepinephrine (NE),adrenocorticotropic hormone (ACTH) and corticosterone (CORT) in blood were measured by enzyme-linked immunosorbent assay (ELISA). Results Related indexes of group test were compared with group control,the body weight gain were lower and blood pressure were higher ( P<0.05).The expressions of mRNA and protein of NF-κB p65 were higher ( P<0.05).The indexes of NE,EPI,ACTH and CORT were higher and IL-2 got lower ( P<0.05). Conclusion The animal welfare would be infected by chronic stress,and should be paid attention to during the animal experiment studies.

Objective To explore the effect of tooth grinding stone in mice and rats breeding. Methods Thirty C57BL/6 mice and 30 SD rats were randomly divided into 2 groups respectively at the age of 3 weeks. Group 1 was as control, and group 2 was given tooth grinding stone in cages, with 3 animals in one cage. All animals had free access to water and everyday weighed feed, the feed consumption were monitored. All animals were tested by open field test 3 months later. Results The feed consumption of group 1 was higher than group 2. Animals in group 2 like playing with the tooth grinding stone. Open field test show that there was no difference between group 1 and group 2 in the activity factor and emotionality factor. Conclusion Tooth grinding stone could save feed and make the life of animals colorful.

Animal experiments are indispensable means for biomedical research. Laboratory animals play an important role in the development of science. With the social development, people pay more attention on animal welfare. For the purpose of improving and implementing animal welfare, this article discusses the necessity of the implementation of the laboratory animal welfare, explicit its historical development, compares the current situation in our country with abroad, and discusses the influential factors of the laboratory animal welfare and its improvement measures, the main purpose is to let laboratory animal scientists put more effect on animal welfare, while ensure animal welfare through guide people to implement animal welfare.

As the important experimental materials for life science, laboratory animals will be faced with the choice of humane endpoint after achieved the scientific goals and objectives. Laboratory animal welfare laws and regulations are relatively perfect in typical developed countries. Studying the choice and practice of humane endpoint in the laws and regulations of experimental animals in typical developed countries has the enlightenment function to laboratory animal welfare legislation in China.

Zebrafish as an ideal animal model was widely used in scientific experiments. In recent years, with the increase in its research and application, the number of zebrafish used is increasing. But the zebrafish‘s breeding management, operation and the welfare has less been reported, and also there is no SOP. To solve this problem, this article reviews the relevant laws and regulations, guidelines and literature, zebrafish‘s breeding management(Transportation, environmental conditions, equipment maintenance), operation (Breeding, identification mark, anesthesia and euthanasia) and the welfare has been discussed respectively. This paper aims to provide a relevant reference for other researchers, to protect and improve the welfare of zebrafish.

Objective To study the impact of frequently-used material intervention measures towards stress-related index of laboratory animals. Methods Sixty weaning male KM mice were randomly assigned to five groups: A was routine feeding group, B nutritional intervention group, C sunflower seed group, D toy group, and E incense group, with 12 mice in each group. Food and water intake were measured every day. Body weight was measured every two days. Blood sample was collected 37 days later from the caudal vein in mouse tail and blood routine examination has been performed. mRNA index of GR, POMC, nNOS, BDNF, NMDA, TH and TPH in brain tissues of the mice were measured by fluorescent real-time PCR method and differences between material intervention groups and routine feeding group were compared. Results Compared with group A, the body weights of mice in other groups reduced. For food intake, group B reduced compared with group A, while group D and E increased. For water intake, group B reduced compared wtih group A, while group D and E increased. For the level of BDNF mRNA expression, comparing with group A, group F and E increased obviously, while group C reduced to some extent. For the level of GR mRNA expression, comparing with group A, group D reduced obviously, while group C and E reduced to some extent. For the level of POMC mRNA expression, comparing with group A, group D reduced to some extent, while other groups reduced significantly. For the level of NMDA mRNA expression, comparing with group A, group D increased obviously. For the level of TH mRNA expression, comparing with group A, group B and C reduced to some extent. For the level of TPH mRNA expression, comparing with group A, group C reduced to some extent. Hematological parameters had no obvious difference among all groups. Conclusions Placing toys makes food and water intake rise sharply, ability to resist fear and anxiety enhanced obviously, learning and memory ability reinforced greatly and stress-related index reduced evidently. Incense makes food and water intake go up, ability to resist fear and anxiety enhanced obviously and stress-related index reduced evidently .

Objective To study improvements in well-being of minipigs with multi-welfare strategies (combine with music, aromatherapy oils, nutrients, toys, biological activity bedding). Methods Twelve female Bama minipigs from 6 litters were used in this study, while every 2 pigs from the same litter were divided separately into conventional group and optimized group. After 9 weeks’ rearing, the expression of stress-related molecules, immune balance, blood parameters and growth performance were measured. Results Pigs from optimized group display lower serum cortisol level and lower IFN-γ/IL-4 as well as lower expression in GR mRNA and HSP70 mRNA, meanwhile their RBC, HGB, HCT, MCV, MCH, WBC, NEUT and EO were observed higher than those from conventional group. Conclusion Multi-welfare strategies is benefit to reduce stress lever of minipigs and enhance their anti-stress ability, meanwhile, it can also change the immune balance and blood routine.

Laboratory animal behavior colligates the wild and wonderful ways in which animals interact with each other living beings, and with the environment. These behavior is the product of an individual’s innate qualities (“nature”) versus those shaped by personal experience (“nurture”). Environment contains all the resources with which the animals come directly in contact. This article reviews the effects of environment factors on laboratory animal behavior. Based on the related standards, the paper explores the relationship between environment control and laboratory animal holding, which will benefit the animal welfare.