Brandt's Vole Research Articles

Regulatory mechanisms of Capillaria hepatica infection on Brandt's Vole (Lasiopodomys brandtii) population

Parasite infection not only triggers the immune response of the host but also potentially affects the reproductive status, thereby influencing the population size. Therefore, understanding the impact of parasite infection on host immune and reproductive systems has long been an important issue in ecological research. To address this, we conducted field surveys (2021–2023) to investigate Capillaria hepatica infection status in Brandt's vole (Lasiopodomys brandtii) and performed controlled experiments in semi-natural enclosures and indoor laboratories. The results showed a negative correlation between the population size of Brandt's vole and the infection rate. To further explore the regulatory mechanisms, transcriptomic and proteomic analyses were performed on the infected BALB/c mice. The study found that post-infection with Capillaria hepatica, up-regulated genes and proteins in the mice liver were primarily associated with immune functions, while down-regulated genes and proteins were related to metabolic functions such as retinol metabolism. Through validation experiments supplementing retinol to the host infected with Capillaria hepatica, it was found that infection with Capillaria hepatica leads to a decrease in systemic available retinol levels, disrupting the expression of the hypothalamic-pituitary-gonadal (HPG) axis hormones, affecting the expression of CYP17A1, thereby regulating testosterone secretion related to spermatogenesis. This process results in abnormal spermatogenesis in the testes, thereby impacting the reproductive capacity of mice. This suggests that Capillaria hepatica regulates resource allocation in hosts, striking a “trade-off” between reproduction and survival, thereby exerting control over population size. These discoveries are crucial for comprehending the interaction between Capillaria hepatica and hosts, as well as their impacts on host reproduction and immune systems, and provide a scientific basis for controlling the transmission of Capillaria hepatica.

Brandt's vole (Lasiopodomys brandtii) affects the dominant position of three gramineous species by altering defense traits and interspecific competition.

Rodents can cause considerable changes in plant community composition. However, relationships between shifts in species dominance and plant functional traits caused by rodents have seldom been investigated, especially for belowground functional traits. In this study, a set of enclosures was constructed to analyze the effects of 10 years of Brandt's voles' activities on the defense strategies and dominant position changes of three gramineous plants (Leymus chinensis, Stipa krylovii, and Cleistogenes squarrosa) in Inner Mongolia. Here, we measured the dominance, biomass, and fourteen functional traits of three plants. The effects of Brandt's voles on dominance, biomass, and functional traits were analyzed, and then we explored the effect of functional traits on plant dominance by using the structural equation model. Results showed that long-term feeding by Brandt's voles resulted in a significant decrease in the dominance of L. chinensis and S. krylovii, whereas C. squarrosa was positively affected. The belowground biomass of L. chinensis and S. krylovii was higher in the vole treatment, which showed that they were increasing their escape characteristics. The leaf thickness of L. chinensis and the leaf C:N ratio of S. krylovii significantly increased, while the specific leaf area of C. squarrosa significantly decreased. All three gramineous showed increased resistance traits in response to Brandt's voles, which positively affected their dominance. Tolerance-related traits of S. krylovii significantly increased, with the increasing growth rate of root length contributing to enhancing its dominance. We highlight that selective feeding by rodents led to the selection of different defense strategies by three gramineous plants, and that changes in biomass allocation and functional traits in the different species affected plant dominance, driving changes in the plant communities.

Tannic acid alleviates 3-nitropropionic acid-induced ovarian damage in Brandt's vole (Lasiopodomys brandtii).

Tannic acid (TA) is a polyphenol with antioxidant properties present in various plants. In this study, we explored the protective effect of TA against ovarian oxidative stress in Brandt's voles and its underlying mechanism. At various doses, 3-nitropropionic acid (3-NPA) was intraperitoneally injected into Brandt's voles to simulate ovarian oxidative stress. Thereafter, various doses of TA were intragastrically administered to examine the protective effect of TA against 3-NPA-induced ovarian damage. Changes in inflammation, autophagy, apoptosis, and oxidative stress-related factors were investigated through various biochemical and histological techniques. Ovarian oxidative stress was successfully induced by the intraperitoneal administration of 12.5 mg/kg 3-NPA for 18 days. As a result, the ovarian coefficient decreased and ovarian tissue fibrosis was induced. TA treatment effectively alleviated the increase in luteinizing hormone and follicle-stimulating hormone levels; the decrease in estradiol, progesterone, and anti-Müllerian hormone levels; and the decline in fertility induced by 3-NPA. Compared to that in the 3-NPA group, TA decreased the expression of autophagy-related proteins beclin-1 and LC3, as well as the level of apoptosis. It also activated the AKT/mTOR signaling pathway, downregulated PTEN and p-NF-κB expression, and upregulated Nrf2 expression. In conclusion, our findings indicate that TA could inhibit autophagy via the regulation of AKT/mTOR signaling, suppressing oxidative damage and inflammatory responses through Nrf2 to alleviate 3-NPA-induced ovarian damage. Collectively, the current findings highlight the protective effects of TA in Brandt's vole, where it promotes the maintenance of normal ovarian function.

Effects of juvenile situational experience on behavioral development of Brandt's vole (Lasiopodomys brandtii): From cognition to psychology

AbstractJuvenile situational experiences that animals are exposed to different environmental conditions have the potential to shape the developmental trajectory of individuals, influencing their personality traits, anxiety level, cognition, and memory. However, empirical evidence regarding these effects remains limited. In this study on male Brandt's voles (Lasiopodomys brandtii) undergoing weaning process, we examined the consequences of juvenile situational experiences on their behavioral development, involving daily exploration of newly introduced objects with a diverse array of materials, shapes, sizes, and colors. The results showed that (1) the situational experience improved spatial cognition and memory, as evidenced by significantly higher scores in both the recognition index during test period (RIB) and the discrimination index during test period (DI) compared to the control group; (2) no significant differences were observed in autonomic activity between the two groups, including total distance traveled, resting time, mean speed, maximum speed, and duration of slow and fast movements across the entire arena; (3) situational experience reduced anxiety levels, indicated by increased exploration of the center area, more transitions between zones, shorter latency to enter the center zone, prolonged resting time in the center area, and greater total time spent and distance moved in the center area; and (4) the situational experience group exhibited significantly higher individual personality scores compared to the control group. In conclusion, our results imply that juvenile situational experience exerts significant positive effects on spatial cognition and memory, anxious behavior, and personality development in L. brandtii. These insights offer novel perspectives on the long‐term impacts of juvenile situational experiences on adulthood, with potential applications in addressing mental health and behavioral anomalies. Additionally, our study provides practical implications for animal management and environmental enrichment strategies.

Brandt's vole hole detection and counting method based on deep learning and unmanned aircraft system.

Rodents are essential to the balance of the grassland ecosystem, but their population outbreak can cause major economic and ecological damage. Rodent monitoring is crucial for its scientific management, but traditional methods heavily depend on manual labor and are difficult to be carried out on a large scale. In this study, we used UAS to collect high-resolution RGB images of steppes in Inner Mongolia, China in the spring, and used various object detection algorithms to identify the holes of Brandt's vole (Lasiopodomys brandtii). Optimizing the model by adjusting evaluation metrics, specifically, replacing classification strategy metrics such as precision, recall, and F1 score with regression strategy-related metrics FPPI, MR, and MAPE to determine the optimal threshold parameters for IOU and confidence. Then, we mapped the distribution of vole holes in the study area using position data derived from the optimized model. Results showed that the best resolution of UAS acquisition was 0.4cm pixel-1, and the improved labeling method improved the detection accuracy of the model. The FCOS model had the highest comprehensive evaluation, and an R2 of 0.9106, RMSE of 5.5909, and MAPE of 8.27%. The final accuracy of vole hole counting in the stitched orthophoto was 90.20%. Our work has demonstrated that UAS was able to accurately estimate the population of grassland rodents at an appropriate resolution. Given that the population distribution we focus on is important for a wide variety of species, our work illustrates a general remote sensing approach for mapping and monitoring rodent damage across broad landscapes for studies of grassland ecological balance, vegetation conservation, and land management.

Physiological indices and liver gene expression related to glucose supply in Brandt's vole (Lasiopodomys brandtii) exhibit species- and oxygen concentration-specific responses to hypoxia

Brandt's vole (Lasiopodomys brandtii) is a species with hypoxia tolerance, and glucose serves as the primary energy substrate under hypoxia. However, the glucose supply in Brandt's voles under hypoxia has not been studied. This study aimed to investigate characteristics in physiological indices and liver gene expression associated with glucose supply in Brandt's voles under hypoxia. Serum glucose of Brandt's voles remained stable under 10% O2, increased under 7.5% O2, and decreased under 5% O2. Serum lactate increased under 10% O2, decreased under 7.5% O2, increased at 6 h and decreased at 12 h under 5% O2. Liver glycogen increased under 10% O2, remained constant under 7.5% O2, and reduced under 5% O2. Pepck and G6pase expression associated with gluconeogenesis decreased under 10% O2, while Pepck expression decreased and G6pase expression increased under 7.5% and 5% O2. Regarding genes related to glycogen metabolism, Gys expression decreased at all oxygen concentrations, Phk expression increased under 5% O2, and Gp expression increased under 7.5% and 5% O2. The alterations in glucose, lactate, liver glycogen, and gene expression related to glycogenolysis in Kunming mice (Mus musculus, control species) are similar to discovery of Brandt's voles under 7.5% O2, but gene expression involved in gluconeogenesis and glycogen synthesis increased. The findings suggest that Brandt's voles are more tolerant to hypoxia than Kunming mice, and their physiological indices and liver gene expression related to glucose supply exhibit species- and oxygen concentration-specific responses to hypoxia. This research offers novel insights for studying hypoxia tolerance of Brandt's voles.

Influence of biotic and abiotic factors on flea species population dynamics on Lasiopodomys brandtii.

Brandt's Vole (Lasiopodomys brandtii) is one of the most abundant rodent species in the grasslands of Inner Mongolia, China, and one of the main carriers of Yersinia pestis, the plague bacterium. There have been several instances of plague transmission among L. brandtii, and all of their dominant flea species are known carriers of plague. Little work has been done to understand the regulation of flea abundance on L. brandtii by biotic and abiotic factors. Here, we examine the impacts of host and climate variation on flea abundance on L. brandtii in May, July, and September of 2021 in the East Ujumqin Banner, Xilinhot City, Inner Mongolia Autonomous Region. We arrived at the following conclusions: 1) There were 8 flea species representing 2 families and 5 genera collected from L. brandtii, and Frontopsylla luculenta, Neopsylla pleskei orientalis, and Amphipsylla primaris mitis were most common. 2) Host body weight, host age, season, temperature, and humidity are key factors influencing flea abundance on L. brandtii. 3) Flea species vary in their respective responses to factors.

Multiple infections of zoonotic pathogens in wild Brandt's voles (Lasiopodomys brandtii).

The frequent interactions of rodents with humans make them a common source of zoonotic infections. Brandt's vole is the dominant rodent species of the typical steppe in Inner Mongolia, and it is also an important pest in grassland. To obtain an initial unbiased measure of the microbial diversity and abundance in the blood and intestinal tracts and to detect the pathogens carried by wild Brandt's voles in Hulun Buir, Inner Mongolia. Twenty wild adult Brandt's voles were trapped using live cages, and 12 intestinal samples were collected for metagenomic analysis and 8 blood samples were collected for meta-transcriptomic analysis. We compared the sequencing data with pathogenic microbiota databases to analyse the phylogenetic characteristics of zoonotic pathogens carried by wild voles. A total of 122 phyla, 79 classes, 168 orders, 382 families and 1693 genera of bacteria and a total of 32 families of DNA and RNA viruses in Brandt's voles were characterized. We found that each sample carried more than 10 pathogens, whereas some pathogens that were low in abundance were still at risk of transmission to humans. This study improves our understanding of the viral and bacterial diversity in wild Brandt's voles and highlights the multiple viral and bacterial pathogens carried by this rodent. These findings may serve as a basis for developing strategies targeting rodent population control in Hulun Buir and provide a better approach to the surveillance of pathogenic microorganisms in wildlife.

Gut Microbiota is Associated with Aging-Related Processes of a Small Mammal Species under High-Density Crowding Stress.

Humans and animals frequently encounter high-density crowding stress, which may accelerate their aging processes; however, the roles of gut microbiota in the regulation of aging-related processes under high-density crowding stress remain unclear. In the present study, it is found that high housing density remarkably increases the stress hormone (corticosterone), accelerates aging-related processes as indicated by telomere length (in brain and liver cells) and DNA damage or inflammation (as revealed by tumor necrosis factor-α and interleukin-10levels), and reduces the lifespan of Brandt's vole (Lasiopodomys brandtii). Fecal microbiota transplantation from donor voles of habitats with different housing densities induces similar changes in aging-related processes in recipient voles. The elimination of high housing density or butyric acid administration delays the appearance of aging-related markers in the brain and liver cells of voles housed at high-density. This study suggests that gut microorganisms may play a significant role in regulating the density-dependent aging-related processes and subsequent population dynamics of animals, and can be used as potential targets for alleviating stress-related aging in humans exposed to high-density crowding stress.

Changes in gene expression and enzyme activity related to glucose metabolism in the livers of Brandt's voles (Lasiopodomys brandtii) exposed to hypoxia

Brandt's vole (Lasiopodomys brandtii) is a hypoxia-tolerant species, and the metabolic characteristics of hypoxia-tolerant species have become a focus of recent research. However, insights into the anaerobic and aerobic metabolism of the livers of Brandt's voles under hypoxia remain limited. In this study, Brandt's voles and hypoxia-intolerant Kunming mice (Mus musculus, control species) were exposed to hypoxia conditions (Brandt's voles, 10% and 7.5% O2; Kunming mice, 10% O2) for 24 h, and changes in gene expression and enzyme activity related to anaerobic and aerobic metabolism in the livers were evaluated. Phosphofructokinase 1 (PFK1), phosphofructokinase 2 (PFK2), pyruvate kinase muscle (PKM), hexokinase 2 (HK2), and lactate dehydrogenase (LDH) related to anaerobic metabolism in the livers of Brandt's voles were increased under 7.5% O2. Regarding gene expression and enzyme activity for aerobic metabolism in Brandt's voles under 7.5% and 10% O2, pyruvate dehydrogenase kinase 1 (PDK1) expression was up-regulated, and succinate dehydrogenase (SDH) activity was decreased. In the livers of Kunming mice, gene expression related to anaerobic and aerobic metabolism was increased at the late stage of 10% O2, and SDH activity was enhanced at 6 h and reduced at 18 h. In addition, PFK1,PKM, PDK1 expression and SDH activity in Brandt's voles were significantly correlated with HIF-1a expression. PFK1, PKM, LDHand PDK1 expression in Kunming mice were significantly correlated with HIF-1a expression. These findings indicate that the livers of Brandt's voles have a certain tolerance to hypoxia, and metabolic changes play important roles in hypoxia tolerance.

Ecology: Voles engineer safe spaces

Ecosystem engineers are typically seen as organisms whose activities modulate the availability of resources for other species. A new study shows that Brandt's vole engineers its local environment specifically to reduce its own risk of being killed by predatory birds.

内蒙古草原布氏田鼠与绵羊的营养生态位研究

PDF HTML阅读 XML下载 导出引用 引用提醒 内蒙古草原布氏田鼠与绵羊的营养生态位研究 DOI: 10.5846/stxb202109142578 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31971429，31272320） Trophic niches of Brandt's vole (Lasiopodomys brandtii) and sheep (Ovis aries) in the Inner Mongolia Grassland Author: Affiliation: Fund Project: The National Natural Science Foundation of China (31971429; 31272320) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:放牧活动对小型啮齿动物种群数量的影响是草原生态系统研究中的热点问题，确定绵羊和小型啮齿动物的营养生态位关系对于草原生态系统的管理具有重要的作用。运用粪便显微分析法分析了内蒙古草原动物生态研究站大型野外围栏内布氏田鼠和绵羊在6-9月份的食谱组成，确定两种草食动物食性选择和营养生态位的变化，从食物利用途径揭示放牧活动对布氏田鼠种群数量的影响方式及二者之间的竞争与共存关系。研究结果表明：围栏中共有23种植物，其中糙隐子草、克氏针茅、羊草和刺藜是围栏中的优势植物；布氏田鼠共取食10种植物，绵羊共取食8种植物，禾本植物为两种动物的主要采食植物。布氏田鼠和绵羊的喜食植物种类都存在季节性变化；除7月外，两种动物的食物多样性与围栏植物多样性有显著的正相关关系，表明动物的食性选择受植物资源变化的影响。布氏田鼠和绵羊具有很高的营养生态位重叠度，除8月（0.691）外，6、7、9月份的营养生态位重叠度均高于0.9，表明二者之间存在激烈的食物竞争；放牧活动极显著地降低了禾本科植物的地上生物量，导致布氏田鼠的食物数量减少；放牧处理下布氏田鼠的喜食植物的物种数和营养生态位宽度（除9月）增加，导致布氏田鼠的食物质量下降。以上研究结果说明，较高的营养生态位重叠度引起动物间激烈的食物竞争；放牧会影响围栏中植物资源的变化，进而影响布氏田鼠的食性选择，放牧活动可能通过降低布氏田鼠的食物数量和质量对其种群数量产生负面效应；这也说明适度的放牧活动在增加人类对草场利用的同时，又可降低小型啮齿动物的数量及危害。 Abstract:The influence of grazing activities on the population of small rodents is a hot issue in grassland ecosystem research. The determination of trophic niche relationship between sheep and small rodents plays an important role on the management of grassland ecosystems. In present study, microscopic analysis of feces was applied to analyze the diet composition of Brandt's voles and sheep, whose fecal samples were collected from the Animal Ecology Research Station located in the Maodeng pasture (Xilinhot, Inner Mongolia, China) from June to September, 2012. The changes in diet selection and trophic niches of the two herbivores would be determined to reveal the patterns by which the population of Brandt's vole was affected by grazing activities, and the relationship of competition and coexistence between these two herbivores from the perspective of food utilization. Our results showed that a total of 23 plant species were found in the fence, with Cleistogenes squarrosa, Stipa krylovii, Leymus chinensis, and Dysphania aristata being the dominant plants. Brandt's vole and sheep fed on 10 and 8 plant species, respectively. Gramineous plants were the main forage plants for both animals. Brandt's vole and sheep had their favorite plant species which varied in different seasons; except for that in July, there was a significantly positive correlation between dietary diversity of animals and plant diversity within the fences, suggesting an effect of changes in available plant resources on animals' diet selections. The trophic niche overlap between Brandt's vole and sheep was higher than 0.9 except for that in August (0.691), indicating that there was fierce food competition between the two. In addition, the grazing activities significantly reduced the aboveground biomass of plants from the Gramineae family, leading to a decrease in the quantity of food for Brandt's vole; and grazing activities significantly increased the number of plant species favored by Brandt's voles and the breadth of its trophic niche (except for September), leading to a decrease in the quality of food for Brandt's vole. These results indicated that high trophic niche overlap could cause fierce food competition between animals; grazing could affect the diet selection of Brandt's voles by influencing changes of plant resources in the fences, and grazing activities may have a negative effect on the population of Brandt's vole through reducing the quality and quantity of its food. These findings suggest that moderate grazing activities not only increase the utilization of pastures but also reduce the population of small rodents and their damage. 参考文献 相似文献 引证文献

Antioxidant response to severe hypoxia in Brandt's vole Lasiopodomys brandtii.

The antioxidant defense system is essential for animals to cope with homeostasis disruption and overcome oxidative stress caused by adverse environmental conditions such as hypoxia. However, our understanding of how this system works in subterranean rodents remains limited. In this study, Brandt's vole Lasiopodomys brandtii was exposed to normoxia (21% O2 ) or hypoxia (mild or severe hypoxia: 10% or 5% O2 ) for 6 h. Changes in key enzymes of the classic enzymatic antioxidant system at both mRNA and enzyme activity levels, and tissue antioxidant levels of the low-molecular-weight antioxidant system were determined in brain, liver, and kidney. Transcript levels of the upstream regulator NF-E2-related factor 2 (Nrf2) were also measured. We found that the mRNA expression of Nrf2 and its downstream antioxidant enzyme genes in L. brandtii were relatively conserved in response to hypoxia in most tissues and genes tested, except in the liver. Hepatic Nrf2, Cu/Zn SOD, GPx1, and GPx3 levels were significantly upregulated in response to mild hypoxia, whereas Mn SOD level decreased significantly in severe hypoxia. Unmatched with changes at the RNA level, constitutively high and relatively stable antioxidant enzyme activities were maintained throughout. For the low-molecular-weight antioxidant system, an abrupt increase of cerebral ascorbic acid (AA) levels in hypoxia indicated a tissue-specific antioxidant response. Although hypoxia did not cause significant oxidative damage in most tissues tested, the significant decrease in antioxidant enzyme activities (GPX and GR) and increase in lipid peroxidation in the kidney suggest that prolonged hypoxia may pose a critical threat to this species.

The Role Transition of Dietary Species Richness in Modulating the Gut Microbial Assembly and Postweaning Performance of a Generalist Herbivore.

ABSTRACTWhen facing a food shortage, generalist herbivores can respond by expanding their dietary species richness (DSR) to maximize energy collection, regardless of whether forages are preferred or not. Higher DSR usually indicates higher nutrient adequacy and better health. However, the high-DSR diet containing a large proportion of preferred species or a large proportion of less-preferred species means different things to an animal. It is still unknown how different shift patterns in DSR would affect distinctly the performance of animals via altering gut microbiota. We examined the gut microbial composition, diversity, community assembly processes, and performance of a generalist herbivore, Lasiopodomys brandtii, in a feeding experiment with increased levels of simulated DSR shifting from preferred plant species to less preferred ones. We found the survival rate and body growth of Brandt’s voles showed a dome-shaped association with DSR: species performance increased initially with the increase of preferred plant species but declined with the increase of less-preferred food items. Several microbial taxa and functions closely related to the metabolism of amino acids and short-chain fatty acids also showed a dome-shaped association with DSR, which is consistent with the observation of performance change. However, the alpha diversities of gut microbiota increased linearly with DSR. The null model and phylogenetic analysis suggested that stochastic processes dominate at low DSR diets, whereas deterministic processes prevail at high DSR diets. These results suggest that the role of DSR in regulating animal performance by gut microbiota depends on the number of preferred forage items.IMPORTANCE The plant species diversity varies greatly under the influence of both climate change and human disturbance, which may negatively affect the productivity as well as the variability of organisms (e.g., small herbivores) at the next trophic level. It is still unknown how gut microbiota of small herbivores respond to such changes in dietary species richness. Our manipulative food experiment revealed that dietary species richness can affect the composition, functions, and community assembly of gut microbiota of Brandt’s vole in a nonlinear way. Given the fast-growing interest in therapeutic diets to treat dysbiosis and to improve health conditions, our study highlights the need to consider not just the variety of consumed food but also the principles of rational nutrition.

Activity overlap between mesocarnivores and prey in the Central Mongolian steppe

Research on the ecology and behaviour of mesocarnivores and their prey is scant in Mongolia. We investigated activity patterns of a guild of mesocarnivores (red fox, Pallas’s cat and beech marten) and their prey (Siberian marmot, Daurian pika, Brandt vole, Mongolian gerbil and Mongolian silver vole) using 21 camera traps (effort = 1155 camera days) in Central Mongolia from 25st of May to 20th August 2019. Activity patterns of mesocarnivores were cathemeral (i.e. no difference between diurnal, nocturnal and crepuscular detections, although activity peaked at sunrise). Among prey, the Siberian marmot and the Daurian pika were diurnal, whereas the Mongolian gerbil and the Mongolian silver vole were not generally crepuscular. Beech marten, the smallest mesocarnivore species, was temporally segregated from the other (and larger) mesocarnivore species. Temporal segregation between mesocarnivores and prey was evident between the following pairs: red fox vs Brandt’s vole and Mongolian gerbil; Pallas’s cat vs Siberian marmot, Brandt’s vole and Mongolian gerbil; and beech marten vs Siberian marmot, Daurian pika and the Mongolian silver vole. Activity overlap between mesocarnivores and prey ranged considerably. Activity overlap between the beech marten and prey was lower than that of the other mesocarnivores. Temporal overlap among mesocarnivores and between mesocarnivores and prey seemed to be related to species-specific traits, while also being mediated by local prey abundance. We suggest future surveys should be stratified based on habitat and on the target species, while also integrating different survey methods (e.g. camera traps and live trapping of small mammals).

Diet of the Pallas's cat (Otocolobus manul) in Mongolian steppe habitat during a population peak of Brandt's voles

Pallas's cats range across Central Asia and commonly consume small mammals. Most studies on Pallas's cats' diets found that they strongly selected particular prey species, such as pika (Ochotona spp.). Pika occurrence in Pallas's cat diet was disproportionately high compared to availability in Central Mongolia. We conducted research into Pallas's cat ecology in Khalzan Soum, Sukhbaatar Aimag since 2018. Brandt's vole density started to increase in 2017, peaked in 2018–2019, and decreased in 2020. We collected feces of Pallas's cats every month from May 2019 to May 2020. During this time, the monthly percent occurrence of Brandt's voles in Pallas's cats' diet ranged from 82.6 to 89.9%. We found a significant correlation between rodent abundance and occurrence in scats of Pallas's cats during the kitten rearing season. Brandt's vole (Lasiopodomys brandtii), Daurian ground squirrel (Ochotona dauurica) and Mongolian hamster (Allocricetulus curtatus) were significantly preferred. Our research provides insights into how Pallas's cats play an important role in biological control in this ecosystem during a Brandt's vole's population irruption.

The effects of dietary diversity on the survival rate and body growth rate of young Brandt's vole

The effects of dietary diversity on the survival rate and body growth rate of young Brandt's vole

Coprophagy prevention alters microbiome, metabolism, neurochemistry, and cognitive behavior in a small mammal.

Many small mammals engage in coprophagy, or the behavior of consuming feces, as a means to meet nutritional requirements when feeding on low-quality foods. In addition to nutritional benefits, coprophagy may also help herbivores retain necessary gut microbial diversity and function, which may have downstream physiological effects, such as maintaining energy balance and cognitive function. Here, we used collars to prevent Brandt's vole (Lasiopodomys brandtii) from engaging in coprophagy and monitored changes in microbial community structure, energy metabolism, and cognitive performance. In this research, we found that coprophagy prevention decreased alpha diversity of the gut microbiota, and altered proportions of microbial taxa such as Bacteroidetes, Firmicutes, and Oscillospira. Preventing coprophagy resulted in a reduced body mass, and increased food intake. Importantly, coprophagy prevention decreased vole cognitive behavior and altered levels of neurotransmitters in brain. Daily acetate administration was able to reverse some of the coprophagy prevention-induced changes in microbiota composition, metabolism, neurochemistry, and cognitive behavior. These findings identify the functional importance of coprophagy behavior and interactions between the gut microbiota, energy metabolism, and neurological function. Our results suggest that coprophagy contributes to stabilizing the gut microbiota, promoting microbial metabolism, maintaining host energy balance and, consequently, altering cognitive performance.

Molecular Characterization of Cryptosporidium spp. in Brandt's Vole in China.

Cryptosporidium spp. are important intestinal parasites that infect humans and various animals, including wildlife. Currently, few epidemiological data in wild rodents, especially in voles, are available. In the present study, a total of 678 Brandt's vole feces samples were collected from Maodeng Livestock Farm and East Ujimqin, Inner Mongolia. The overall prevalence of Cryptosporidium spp. was 18.7%. Significant differences were not found between genders but between locations and weight groups. Moreover, three known species/genotypes, C. suis, Cryptosporidium environmental sequence and muskrat genotype II, and a novel Cryptosporidium species/genotypes of Brandt's vole was identified. To the best of our knowledge, this is the first report of Cryptosporidium spp. infection in Brandt's vole worldwide. These findings imply Brandt's voles might be a potential source of human cryptosporidiosis.

Kinship analysis reveals reproductive success skewed toward overwintered Brandt's voles in semi-natural enclosures.

Age structure and seasonality influence the population fluctuations of small rodents. Age determines body weight and social experience, while seasonality regulates the duration of the breeding season and onset of sexual maturity in newborn offspring. Therefore, reproductive success and skew usually occur in different age groups. Brandt's vole (Lasiopodomys brandtii) is a social, short-lived and seasonal breeding small rodent with a dramatic seasonal population fluctuation, but reproductive skew is not fully understood in this species. In the present study, we determined kinship in semi-natural enclosure populations using microsatellite markers based on genotyping, analyzed the reproductive skew between sexes and between overwintered and newborn voles, and monitored variation in male reproductive activity by testing fecal testosterone levels throughout the year. Overwintered voles had the most reproductive success along with a striking increase in the population size in the enclosures, with all biological fathers and 77.8% of biological mothers, which had 100% and 87% of the total offspring, respectively. Compared to overwintered voles, reproductive skews were significantly higher in potential overwintered and newborn parents, implying the possible reproductive suppression of newborn voles by dominant overwintered voles. Moreover, both heavier body weight and higher testosterone levels in overwintered males supported their potential social status in the population. Our study provided new evidence for reproductive skew and differentiation of postnatal gonadal development patterns of different age groups in Brandt's vole.