Microtus fortis (reed vole) is the only mammal known to have natural resistance to Schistosomiasis japonica. Originating from schistosomiasis endemic and non-endemic areas, as well as laboratory bred voles have the same resistance to Schistosoma japonicum. After more than 30 years of laboratory cultivation of wild reed vole, a series of progress have been made in laboratory animalization. A detailed study was conducted on biological traits including growth and development, reproductive physiology, serum biochemistry, hematological indicators and tissue anatomy. At the same time, the anti-schistosomiasis characteristics and anti-schistosomiasis mechanisms of Microtus fortis were studied. The closed Dongtinghu population of Microtus fortis (S: DTMF) cultivated by Shanghai Laboratory Animal Research Center was recognized as a Chinese laboratory animal resource by the Experimental Animal Resources and Evaluation Working Committee of the Chinese Association for Laboratory Animal Sciences in 2021. This review focuses on summarizing the research progress in the biological characteristics, standardization research, genome and anti-schistosomiasis mechanism of reed vole in the past decade, especially in the implementation of the key project in the National Science and Technology Pillar Program.

Objective To measure and analyze biological characteristics and aging phenotype of SHJH ^hr mice and provide basic data for the application of the mouse model in aging mechanisms research and antiaging drug development. Methods With ICR mice of the same age as control group, the body mass growth data of SHJH ^hr mice at the age of 3 to 16 weeks, the reproduction ability of 1 to 4 fetuses and the life cycle of SHJH ^hr mice were measured. Blood routine (30 items) and serum biochemical indexes (25 items) of 6-week-old SHJH ^hr mice were measured. The venous blood of 8-week-old SHJH ^hr mice was collected for flow cytometry analysis to determine the content of immune cells. The aging bone structure of the cancellous bone and bone mineral density of SHJH ^hr mice aged 4, 8 and 26 weeks were measured by micro-CT. Histopathological changes of bone and joint of 8-week-old mice were observed. Results Compared with ICR mice, the female and male body mass of SHJH ^hr mice were significantly lower at the age of 16 weeks (P < 0.05), and the reproductive performance of female mice was low (P < 0.01) or did not have normal reproductive capacity. The shortest survival time of SHJH ^hr mice was 57 weeks and the longest was 71 weeks, which was shorter than those of normal ICR mice, showing obvious rapid aging phenomenon. At the same time, some physiological and biochemical indexes of blood and pathological changes of bone and cartilage tissues also showed the accelerated aging and abnormality of animal physiological functions. Conclusion SHJH ^hr mice have some biological characteristics of rapid aging as well as some physiological and pathological changes caused by aging.

Objective To analyze the microflora structure and abundance of ileum and colon of SPF male SD rats by high-throughput sequencing technique. Methods The ileal and colonic lumen contents of 30 SPF male SD rats were collected, the total bacterial DNA in the contents was extracted and amplified by PCR. The V3-V4 region of bacterial 16S rRNA in the samples was sequenced using Illumina NovaSeq sequencing platform. Then the species structure and abundance of the intestinal flora were analyzed at the phylum and genus level based on validated data. The diversity and differences between ileal and colonic flora were analyzed using the QIIME software (amplicon) analysis tool. The Tax4Fun program was applied to predict the dominant gene enrichment pathways of ileal and colonic flora. Results At the phylum level, the dominant microflora in the ileum of male SD rats were Firmicutes and Actinobacteria, accounting for more than 98%. The dominant colonic microbial community were mainly Firmicutes and Bacteroidetes, accounting for more than 95%. At the genus level, Lactobacillus and Alistipes were the predominant bacteria in the ileum. The colon was dominated by Lactobacillus and Romboutsia. In terms of flora diversity, the alpha diversity of colonic flora including richness index (Chao1 index) and diversity index (Shannon index) were significantly higher than those of ileum (P < 0.01), and the structural variability of the composition of its flora species was smaller than that of ileum; the ileal flora with significant structural variability were mainly of the phylum Firmicutes, Romboutsia, Peptostreptococcaceae, while the colonic flora had significant structural differences in Bacteroidales. In terms of flora function, the ileal flora dominant genes were significantly enriched in lipid-like metabolism, polyketide metabolism, membrane transport, biodegradation and other pathways, while the colonic flora dominant genes were significantly enriched in glycan biosynthesis metabolism, energy metabolism, biosynthesis of cofactor and vitamins and other products, and other pathways. Conclusion There are significant differences in structure and abundance between the ileal and colonic flora of SPF male SD rats, and the abundance and diversity of colonic flora are higher than those of ileal flora.

Objective Focused on the laboratory animal domestication and breeding of domestic cats, to explore the feeding management methods and breeding techniques of experimental cats. Methods Seven Chinese garden cats from three litters were introduced from the rural suburbs of Guangzhou, and a breeding seed colony was established. The cats were domesticated in captivity, bred, closed breeding and transmission according to the feeding and management methods of laboratory animal. The population reproduction, the number of pregnancies per year, the litter season, the birth and weaning quality of the cats, and the survival rate of weaning were statistically collected. Results The young breeding cats were able to adapt to the cage feeding management. In the transmission breeding and the expanded breeding colony, the number of female cats pregnant with one, two or three litters a year accounted for 63.2%, 26.3% and 10.5%, respectively. The proportions of litters born from the 1st to the 4th quarters were 20.7%, 20.7%, 27.6%, and 31.0%. A total of 29 pregnancies and 101 kittens were got from 19 female cats, with an average of (3.5±1.33) kittens per litter. The birth weights of female and male cats were (89.31±13.69) g and (93.47±15.12) g, respectively. Sixty-seven kittens survived from weaning. The average survival rate was 60.86%, and the weaning weights of female and male cats were (361.62±82.77) g and (376.0±91.71) g, respectively. Conclusion Domestic Chinese garden cats can adapt to laboratory animal feeding and breeding rules, and have strong fertility. They can normally pregnant and breeding throughout the year. The kittens grow to 5-6 months of age can meet the weight requirements for the examination of pharmaceutical hypotensive substances, and can be used as experimental cats for pharmaceutical examination with clear origin.

Objective To explore the histological characteristics of the kidney in Mongolian gerbils of different ages. Methods Ten Mongolian gerbils of 2, 6, and 12 months old (half male and half female) were selected. After euthanasia, the kidneys were taken and paraffin sections were made. After HE, MASSON and PAS staining, the structural differences of different parts of the kidney tissue in gerbils of different ages were observed by digital scanning, and the relevant data of the kidney tissue were measured by image analysis software. Results The number of proximal convoluted tubules was more than that of distal convoluted tubules in the renal cortex and outer medulla of gerbils. With age, the glomerular density decreased, the glomerular diameter increased, the basement membrane of renal tubules thickened, and the fibrous components between renal tubules increased. Conclusion The histological structure of Mongolian gerbil's kidney varies with age, which may be related to glomerulosclerosis and parenchymal cell reduction. The specific mechanism needs further study.

Objective To investigate anatomical characteristics and background lesions in laboratory British-shorthair cats (BSCs) through gross and histopathological examination, and provide effective basis for the research and application, standard establishment and market promotion of this experimental animal. Methods Gross system dissection and histopathological examination were performed on 14 adult BSCs (half male and half female), and the histological characteristics and background pathological data were collected and analyzed. Results The body weight and organ index of spleen of BSCs was higher in males than females (P < 0.05, P < 0.01), the organ coefficients of brain and thymus in BSCs were lower in males than females (P < 0.05). The anatomical structure of testicles, heart, thyroid gland and tentorium of BSCs is different from that of rodents and canine. Furthermore, histopathological examinations revealed that the structures of heart, pancreas, spleen in BSCs differed from two experimental animals mentioned above. In addition, there were multiple hepatic cell vacuolar degeneration in BSCs (9/14), and occasional renal, brain and lymphoid tissues were also found in some animals. Conclusion There were six differences in body weight, and organ-coefficient of spleen, thymus, and brain in BSCs, while the hepatocyte phospholipidosis of liver and background lesion in BSCs were found.

The host digestive tract comprises trillions of commensal microbes, collectively called microbiota. These microbes interact with a various host cell types and have a significant impact on health and disease. High-throughput sequencing technologies have accelerated the identification of numerous poorly studied microbes associated with health and disease. Genetic and humanized mouse models with and without environmental exposure were established to study the roles of these microbes in human physiologies and pathologies. Important findings related to the microbiota, mucosal immunity, and infectious diseases in mouse models are summarized. Furthermore, challenges and opportunities in leveraging genetic approaches and environmental exposure to optimize mouse models are discussed.