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The house mouse (Mus musculus) is often thought of as a pest species in biological conservation, in agriculture, and in urban areas. As a result, populations are frequently targeted for control and eradication. However, M. musculus has notable within‐species biodiversity: it has genetically, morphologically, and behaviorally distinct subpopulations. Conserving biodiversity is usually considered the paramount goal of conservation biology, not least because biodiversity is claimed to have intrinsic value. But the biodiversity in mouse populations is often overlooked. In particular, conservationists do not call for the unique diversity represented by threatened mouse populations to be protected. This is illustrative of the inconsistent valuing of biodiversity in conservation. If biodiversity is intrinsically valuable, then it should be valued; however, it reveals itself. And yet, in examples presented here, unique populations of house mice with clear biodiversity value are threatened by eradication campaigns on islands and by changing agricultural practices on the Swiss–Italian border. The inconsistent valuing of biodiversity in the case of M. musculus raises important questions about whether the intrinsic value of biodiversity in conservation is, in practice, conditional on other implicit assumptions. [ABSTRACT FROM AUTHOR]

Superior rodent management is critical to preserve the diversity of wildlife, and to mitigate environmental and social damage. Pest management strategies can employ 21st century methods to balance the human-animal conflict, especially regarding rodents. Non-toxic fertility control has several advantages over the use of poison when the following parameters are true: 1) rate of removal exceeds rate of population increase; 2) compounds do not bioaccumulate in the rodents or the environment; 3) non-lethal method targets both males and females; 4) animals can be detected at low densities; 5) cost analysis favors fertility control over lethality; 6) method has socio-political acceptance. Our fertility control system meets each of these requirements. Utilizing plant-root-based extracts from Tripterygium wilfordii Hook F, we have formulated a proprietary rodent feed pellet that is efficacious in reducing mice and rat populations in multiple settings. The pellets target rodents with a population reduction capacity of 98% that is sustainable over 12 months. The cost of the pellet solution is less than 90% of other fertility control products, and less than 47% of poison products. The functional key to the success of fertility-control approaches is optimizing feeding protocols to achieve maximum population reduction. We have developed an application-based system to provide sustainable cost-effective management. The monitoring system captures consumption and feeder service data. Point-of-entry data validation is enforced. Compliance with the service program is monitored and configurable alerts are issued for outlying events. These data are ingested into a data analytics engine which generates real-time dashboards for oversight and analysis. Administrative features provide user management, project definition and configuration. In-line instructional documentation and pellet supply order forms provide support for field technicians. As a 501(c)3 non-profit charity we are funded by Open Philanthropy to provide the rigorous data sets presented: a 21st century solution to rodent management.

Invasive commensal rodents are the source of significant harms across diverse ecosystems globally, including biodi­versity loss on islands, economic damage in agricultural settings, and disease spread in urban areas. Genetic tools can provide unique insights and solutions for rodent management or eradication, adding to the toolbox of integrated pest management opera­tions. In real world conditions, the utility of genetic tools for rodent management is constrained by ecological factors such as mating and dispersal behavior, landscape variation, and ongoing management strategies. Here we describe two distinct uses of genetic tools for rodent management and their ecological considerations. First, we describe how patterns of genetic connectivity can inform the establishment of functional management units, discern among scenarios leading to island eradication failure, and provide insights into rodent management outcomes. Second, we discuss the utility and risks of using gene drive systems to eradicate invasive house mice from island environments. We describe aspects of risk assessment and mitigation as well as the utility of computational models for improving gene drive preparedness. Together, we outline the importance of ecologically-informed implementation strategies when using genetic tools, both currently available and in development, for the management of commensal rodents.

Invasive house mice threaten native biodiversity on many of the world’s islands. Best practice for eradicating house mouse populations from islands currently relies on bait containing the anticoagulant rodenticide brodifacoum. These baits are typically either broadcast (by hand or by helicopter in natural areas) or placed in bait stations (in human infrastructure or in areas where open broadcast is not permitted). There have been many successful mouse eradications using these methods, including 29 of 36 attempts of islands being successful (81%) in New Zealand. Following recent failed mouse eradications on Gough Island (South Atlantic, 2021) and Midway Atoll (North Pacific, 2023), a workshop was convened with 24 people attending (16 in-person, 8 on-line) from 7 countries (Australia, Canada, France, NZ, South Africa, UK, US), to discuss some hypotheses for what may have contributed to these unsuccessful outcomes. The workshop was held in Palmerston North, New Zealand, between November 27 and 29, 2023. Discussions over the three days revolved around three hypotheses. We present the key factors hypothesized for why eradications failed on these two islands. We also outline research and operational needs that were identified in the workshop that can contribute to improved outcomes for future eradications of house mice from targeted islands.

Meiotic drive is the biased transmission of alleles from heterozygotes, contrary to Mendel's laws, and reflects intragenomic conflict rather than organism-level Darwinian selection. Theory has been developed as to how centromeric properties can promote female meiotic drive and how conflict between the X and Y chromosomes in males can promote male meiotic drive. There are empirical data that fit both the centromere drive and sex chromosome drive models. Sex chromosome drive may have relevance to speciation through the buildup of Dobzhansky-Muller incompatibilities involving drive and suppressor systems, studied particularly in Drosophila. Centromere drive may promote fixation of chromosomal rearrangements involving the centromere, and those fixed rearrangements may contribute to reproductive isolation, studied particularly in the house mouse. Genome-wide tests suggest that meiotic drive promotes allele fixation with regularity, and those studying the genomics of speciation need to be aware of the potential impact of such fixations on reproductive isolation. New species can originate in many different ways (including multiple factors acting together), and a substantial body of work on meiotic drive point to it being one of the processes involved. [ABSTRACT FROM AUTHOR]

The house mouse is the best-studied mammal species after humans, yet our understanding of its evolutionary history remains incomplete. Here, we focused on the colonisation of Europe by two subspecies and formation of a hybrid zone between them. We carried out a large-scale study of ~7000 mice sampled across an area embracing an ~900 km long portion of the zone, supplemented with cytochrome b and D-loop sequencing of ~1200 individuals collected worldwide. We demonstrate that the course of the mtDNA contact front is intricate and highly discordant with the consensus front for autosomal and X-linked markers, suggesting that local snapshots of mtDNA introgression may be misleading when treated in isolation. While multiple unrelated M. m. domesticus haplotypes occur in the zone area, the diversity of M. m. musculus haplotypes is limited. Moreover, we uncovered a vast region of domesticus introgression into musculus territory in northern areas and showed this introgression is unlikely to be driven by positive selection. We consider two previously published hypotheses explaining this phenomenon and put forth an alternative scenario assuming associations between mice and humans in northern Europe during the Nordic Bronze Age and subsequent zone movement associated with the expansion of Balto-Slavic peoples. [ABSTRACT FROM AUTHOR]

Biogeography and the occurrence of small mammals are usually hard to investigate due to the small size and secretive habits of these mammals. Available data are particularly insufficient on minor islands and at national borders, where research efforts are usually scarce. Here we briefly updated the knowledge on murid rodents on two remote Italian small islands (Lampedusa and Pantelleria) at the southernmost Italian borders. During summer 2019, house mice and rats were sampled in Lampedusa and Pantelleria and molecular markers were sequenced for species identification. The new sequences of Mus domesticus were also compared with samples from previous works collected in Lampedusa, Pantelleria, and several localities in the Mediterranean basin. Moreover, our analyses provided the first genetic evidence of the occurrence of Rattus norvegicus in Lampedusa. To conclude, R. rattus was confirmed to be present in Pantelleria. The newly collected haplotype of M. domesticus from Pantelleria is similar to those currently known for Sicily, whereas the new haplotype from Lampedusa partially diverges from the ones previously described, and clusters with haplotypes from North Africa and the Middle East.

Context: Invasive rodents pose a substantial threat to biodiversity and are a leading cause of species decline and extinction on islands. Population suppression using ground-based methods is common practice, though arboreal behaviour of rodents may render control programs less effective. Aims: We aimed to quantify species-specific invasive rodent activity (Rattus rattus , R. exulans , Mus musculus) across three forest strata to determine the prevalence of arboreal rodent behaviour in a system that has undergone extensive long-term rodent baiting, and therefore assess the suitability of solely ground-based baiting in this system. Methods: We calculated rodent presence at the ground, mid-storey, and canopy using three detection methods (camera traps, chew cards and tracking tunnels) deployed for 30-day periods across three structurally distinct forest types (canopy heights ranged from 3.5 to 16.7 m). We developed continuous rodent activity indices for each method, which we paired with density estimates. Strata-specific species composition was determined using camera trap images. Key results: Rodent presence was recorded equally across all strata, with R. rattus dominating above-ground strata. Rodent densities differed significantly between forest types, which was largely consistent with activity indices. Conclusions: Our findings offer an additional explanation for reduced efficacy of long-term ground-based control programs: arboreal behaviour may exacerbate the reduction in efficacy often associated with long-term control. Implications: Effective management of invasive rodent species on islands is a global conservation challenge. Our findings suggest above-ground control may be required in some long-term suppression programs or eradication campaigns, particularly in the presence of the black rat. Introduced rodents are highly destructive island invaders the world over. Control programs are usually ground-based, however our study found that black rats (Rattus rattus) dominated the forest mid-storey and canopy, casting doubt on the effectiveness of solely ground-based programs. Including above-ground control in the conservationist's rodent control arsenal may improve outcomes for island biodiversity. [ABSTRACT FROM AUTHOR]

Aotearoa—New Zealand has only four rodent species, all introduced. In order of arrival, they are Pacific rat Rattus exulans, brown rat R. norvegicus, house mouse Mus musculus, and black rat R. rattus. Rodent management in New Zealand aims mainly to conserve indigenous biodiversity rather than to protect crops or manage diseases, as is usual elsewhere. We describe four major "regimes" and one major vision for rodent control in New Zealand to meet ecological restoration objectives. Current challenges for island eradications are for large islands that are remote or populated by people. Aerial 1080 is the only large‐scale (tens of thousands of hectares) option for black rat control, but its application requires adjustment to counter subsequent rapid black rat repopulation. Unfenced "ecosanctuaries" (mean 720 ha) use ground‐based traps and poisons to target mainly black rats and face constant reinvasion. Ecosanctuaries with mammal‐resistant fences (up to 3500 ha) limit reinvasion and target more pest species and have enabled the return of previously extirpated taxa to the main islands. Predator Free 2050 aims to eradicate the rat species (but not mice) plus some other introduced mammals from New Zealand by 2050. This vision is not attainable with current tools, but research and experimental management is exploring techniques and technologies. The large scale (to 100 000 ha) at which black rats are now targeted for control to extremely low abundance seems to be unique to New Zealand. [ABSTRACT FROM AUTHOR]

Invasive rodents threaten native species in numerous ecosystems, especially oceanic islands. The House Mouse Mus musculus is the only introduced mammal species on sub-Antarctic Gough and Marion Islands. Ample evidence exists of mice preying upon seabird chicks on these two islands, but there have been only a few reports of attacks on adult seabirds, none of which has been fatal. We report the first deaths of adult great albatrosses due to mouse attacks. On Gough Island, three Tristan Albatrosses Diomedea dabbenena (Critically Endangered) brooding small chicks were observed with wounds typical of mouse attacks in March–April 2021; two likely abandoned their chick, causing breeding failure, and the third was found dead eight days after discovery with large blowfly larvae in the wound. On Marion Island, two wounded and eight dead adult Wandering Albatrosses D. exulans (Vulnerable) were found in April 2023. Inspection of the wounded individuals, as well as the injuries on the fresh carcasses strongly suggest that mouse predation was the cause of death. Gough Island is home to virtually all Tristan Albatrosses, and Marion Island is the single most important breeding site for Wandering Albatrosses, home to about a quarter of all breeding birds. The death of breeding adults of these long-lived species emphasizes the urgent need to eradicate introduced mice from these islands. [ABSTRACT FROM AUTHOR]

In ancient times, rodents were a major problem causing economic losses and an epidemiological threat due to the bacteria and parasites they carried. Ancient authors primarily mentioned field mice and house mice, which ate the grain, contaminated the land and food intended for humans and animals, and caused damage within the house and farm buildings. Most of the advice preserved from those times was on how to exterminate rodents, with only few texts providing recommendations on how to protect farm buildings and grain from mice. Ancient poison formulas primarily relied on poisonous plants and were usually served in cake form or added to food. There are some differences within the recommended poisons. More toxic substances were used in the farmyard and outbuildings than in the houses, which probably has to do with the risk that these poisons, due to their composition, posed to people and especially children. [ABSTRACT FROM AUTHOR]

Furry animals, such as dogs and cats, are permanently settled in our homes. Many people cannot imagine life without their favorite pet. Unfortunately, the appearance of animals in the human environment is associated with exposure to numerous allergens. Allergy to fur animals is currently a relatively common form of sensitization and affects both adults and children. The possibility of diagnosing sensitization to specific proteins that are found in animal secretions and knowledge about the biological role of these allergens allows patients to give more detailed and adequate recommendations. However, the correct interpretation of sensitization to allergen components is still a challenge for the clinician. In the first part of the review the allergens (accepted by the WHO/IUIS Allergen Nomenclature Committee) of dog, cat, guinea pig, jungle hamster, Syrian hamster, house mouse and rat were characterized. The review article presents a compendium of information about the known allergens, which, we hope, will prove useful in the daily work of an allergist. [ABSTRACT FROM AUTHOR]

Introduction Major depressive disorder is a common mental health disorder characterized by a high incidence among women. (1) The World Health Organization has reported that depression seriously endangers women's health [...], Background: The postpartum period is a complex time for females that affects health recovery. Stress during this period is one of the main risk factors for depression. Therefore, preventing stress-induced depression in the postpartum period is of great importance. Pup separation (PS) is a natural paradigm of postpartum care; however, the effect of different PS protocols during lactation on stress-induced depressive behaviours in dams is unknown. Methods: Lactating C57BL/6J mice were subjected to no pup separation (NPS), brief PS (15 min/day, PS15) or long PS (180 min/day, PS180) from postpartum day 1 to postpartum day 21 and were then subjected to chronic restraint stress (CRS) for 21 days. Behavioural tests, specifically the open field test (OFT), elevated plus maze (EPM) test and tail suspension test (TST), were performed. The expression of mRNA and protein in the hippocampus and microbiota composition were also assessed. Results: We observed CRS-induced anxiety- and depression-like behaviours in NPS dams. In addition, in NPS dams, microglial activation and the levels of NOD-like receptor pyrin domain containing 3, caspase-1 and interleukin-1[beta] were increased, whereas expression levels of collapsing response mediator protein 2 (CRMP2) and [alpha]-tubulin were decreased. However, immobility time in the TST was lower in PS15+CRS dams than in NPS+CRS dams, and time spent in the centre during the OFT and in the open arms during the EPM test was higher in PS15+CRS dams, indicating resilience. Expression of hippocampal biomarkers of neuroinflammation was inhibited and levels of CRMP2-mediated neuroplasticity were increased in PS15+CRS dams. Notably, we observed taxonomic changes in the cecal microbiota across different PS groups, as well as relationships between gut microbiota composition and some biomarkers of hippocampal neuroinflammation and neuroplasticity. Limitations: The sample size for gut microbiota analysis in this study was small. Conclusion: Collectively, the results of this study confirm that brief PS confers stress resilience in CRS-induced behavioural deficits and reverses hippocampal neuroinflammation-neuroplasticity injury and gut microbiota imbalance.

AbstractWe tested the climbing ability of two native Hungarian rodent species under laboratory conditions. One mouse species is the mound-building mouse (Mus spicilegus), which is associated with flat, arable environments; the other is the house mouse (Mus musculus), which occurs in many natural and artificial environments following human settlements. We sought answers to the following questions, whether each of these species can use the vertical dimension and whether there is a difference in climbing ability between individuals of different ages of the two species. From our results, we concluded that the climbing ability of mound-building mice is much lower than that of house mice, but young mound-building mice show a much greater inclination towards climbing than adult mound-building mice.

The ectoparasites of introduced rodents in mainland New Zealand forests include several species of cosmopolitan flea that may be important in the population dynamics and future biocontrol of rodents. We describe a 2-rodent, 2-flea system that showed little change over 20 years. Ship rats (Rattus rattus) and house mice (Mus musculus) were snap trapped at fixed sites in the Orongorongo Valley, Wellington, for a study of their population ecology. The fleas Leptopsylla segnis and Nosopsyllus fasciatus were common on mice and rats respectively, and less common on the alternate hosts. Prevalence was described in relation to sex and age of the host, and to season and year. Male mice were more likely than females to carry L. segnis. Prevalence and intensity of infection mostly increased with age of host. Prevalence of both flea species showed modest seasonal variation, with a dip in autumn. Pregnant or lactating female rats and mice were less likely to have fleas than were non-breeding adult females. Prevalence did not vary positively with host density. We detected a slight overall increase in the prevalence of each flea species over the duration of the study. We conclude with some discussion of flea assemblages in New Zealand. [ABSTRACT FROM AUTHOR]

We analyzed the influences of interspecific interactions and environmental factors on rodent community assembly in Mojave Desert wetlands that support the endangered Amargosa vole (Microtus californicus scirpensis). A total of 4927 rodents in six species were captured from 2010 to 2021 within 15 marshes, most frequently including Amargosa voles, harvest mice (Reithrodontomys megalotis), and house mice (Mus musculus), an invasive species. The structure of the community varied considerably over time and by marsh, driven mainly by reductions in harvest mice and increases in Amargosa voles and house mice between 2014 and 2017, and then reductions in Amargosa voles between 2018 and 2021. Northern marshes were dominated by voles, and southern marshes by house mice. Primary determinants of rodent capture rates were interspecific interactions, human proximity, and season. There was a significant inverse relationship between vole and house mouse captures per session, suggesting competitive exclusion. Distance to the nearest town was positively associated with the numbers of voles and negatively associated with the numbers of harvest mice, suggesting that voles may be more sensitive to human disturbance than other rodents. Amargosa voles and harvest mice had annual population cycles with peaks between July and September occurring 6–7 months after rainfall. Our results allow for valuable insight into the influences on community dynamics in desert rodents and highlight that conservation efforts that support Amargosa voles may simultaneously help control house mouse abundance and expansion. [ABSTRACT FROM AUTHOR]

Lymphocytic choriomeningitis mammarenavirus (LCMV) is a globally distributed zoonotic pathogen transmitted by house mice (Mus musculus). We report the reemergence of LCMV (lineages I and II) in wild house mice (Mus musculus domesticus) and LCMV lineage I in a diseased golden lion tamarin (Leontopithecus rosalia) from a zoo in Germany.

Abstract Background House mice are commensal animals with a nearly global distribution, structured into well differentiated local populations. Besides genetic differences between the populations, they have also diverged behaviorally over time, whereby it remains open how fast general behavioral characteristics can change. Here we study the competitive potential of two very recently separated populations of the Western house mouse (Mus musculus domesticus) by using two different approaches—one under controlled cage conditions, the other under more natural conditions in enclosures mimicking a secondary encounter condition. Results We observe a clear bias in the competitive ability towards one of the populations for both tests. The measured behavioral bias is also reflected in the number of hybrid offspring produced in the enclosures. Conclusion Our data suggest that key behavioral characteristics with a direct influence on relative fitness can quickly change during the evolution of populations. It seems possible that the colonization situation in Western Europe, with a rapid spread of the mice after their arrival, would have favored more competitive populations at the expansion front. The study shows the possible impact of behavioral changes on the evolution of populations.