The slug Deroceras laeve has emerged as a valuable model for biological research, but limited knowledge exists of the microbiota that inhabit the digestive tract of this species. This study assessed the bacterial microbiota of the stomach and intestine of D. laeve fed either a diet formulated for rodents (RD) or a diet of fresh vegetables (VD). Pseudomonadota was the most abundant phylum in both digestive compartments, although it decreased in abundance with the VD diet. The genus Rahnella was the most abundant in both regions with a decrease caused by the VD diet and a concomitant increase in richness. Predicted metabolic pathways indicated that fatty acid biosynthesis predominated in the stomach of slugs fed the RD, whereas pyruvate fermentation and amino acid biosynthesis were enriched in VD animals. In the intestine, aerobic respiration, pyruvate fermentation, fatty acid and amino acid biosynthesis were identified as conserved pathways. Predictive functional profiling revealed that signaling and cellular processes, genetic information processing, and metabolism were predominant functions across all groups. These results reveal a more diverse microbiome in slugs fed VD, paralleling the findings in other animals and providing a good grounding for the study of ecological adaptations of this species to its environment.

Grasslands around the world are becoming degraded due to human causes. In British Columbia, Canada, grasslands cover only ~1% of the landmass, yet 20% of species listed as “at-risk” of extinction in British Columbia occupy grasslands. Grassland restoration is therefore important to managing imperiled species. Biosolids (post-treatment sewage) are being used to increase forage for livestock grazing in some areas. These grasslands appear to support high densities of insects and small mammal prey, potentially enhancing populations of owls and raptors. To examine impacts of biosolids on populations of prey and predators, I studied small mammals, raptors, and owls at the OK Ranch, a cattle ranch near Clinton, British Columbia. I quantified differences in North American deermouse (Peromyscus maniculatus) populations on biosolids and control pastures and studied populations of Short-eared Owls (Asio flammeus), Long-eared Owls (Asio otus), and American Kestrels (Falco sparverius), comparing yearly abundance, habitat use, and diet within this biosolids-influenced ecosystem. Deermouse populations were smaller in pastures with biosolids, likely due to an increase in grass cover in these areas, thus indicating these pastures may be being restored. American Kestrels and Short-eared Owls used biosolids pastures over control pastures disproportionate to availability. American Kestrels ate prey that were most abundant each year. When present on the study area, Short-eared and Long-eared Owls primarily ate voles, however Short-eared Owls diversified their diets more in 2019, when vole populations were low. This research has expanded our knowledge about how biosolids can impact small mammal populations and raptor and owl habitat use. These results suggest biosolids could be used in an explicit conservation capacity to help restore wildlife populations on degraded grasslands.

Many neuroinflammatory and neurodegenerative disorders are characterized by characteristic (histo-) pathological changes. In Parkinson’s disease (PD), for example, it is well known that dopaminergic neurons in the substantia nigra of the midbrain degenerate, which results in the dopaminergic denervation of the striatum. To take another example, multiple sclerosis (MS) is characterized by focal, inflammatory lesions of the white matter leading to oligodendrocyte degeneration, demyelination and axonal degeneration. Despite such “classical” pathological events, neuroinflammatory and neurodegenerative disorders are as well characterized by “non-classical“ pathologies. In PD, we now know that besides the striatum other brain areas are subjected to the dopaminergic denervation. In MS, not just the white but as well the gray matter shows widespread and severe demyelination. In this thesis, “non-classical” pathologies in PD and MS animal models are investigated. Special emphasis is placed on astrocytes which are important regulators of brain homeostasis and pathologies. In the first study, pathological changes of cortical and subcortical brain structures were investigated applying the intrastriatal 6-hydroxydopamine (6-OHDA) mouse model, as they may be of particular interest for the understanding of motor and non-motor symptoms in PD. As expected, intrastriatal 6-OHDA injection induced retrograde degeneration of dopaminergic neurons within the substantia nigra pars compacta, but less so within the ventral tegmental area. Furthermore, a region-specific loss of tyrosine hydroxylase (TH)+ fiber density has been observed in distinct extrastriatal structures among the cingulate- and motor cortex. Interestingly, the loss of cortical TH+ fibers was not paralleled by changes in microglia or astrocyte densities or microglia morphology. Besides, in the globus pallidus and thalamus the loss of TH-immunoreactive fibers was paralleled by a strong increase in microglia densities. These results demonstrate that intrastriatal injections of 6-OHDA lead to pathological changes in both cortical and subcortical structures, which can be reproducibly and reliable examined in this model. The identification of putative disease-specific or regionally enriched reactive astrocyte subtypes could be particularly relevant to understand the selective susceptibility of neuronal populations in certain brain regions in PD. The objective of this second study was to reveal histological similarities and differences in astrocyte numbers and morphologies during 6-OHDA-induced striatal denervation depending on the marker protein used. Marked differences were already evident in the non-lesioned mouse striatum. While astrocytes in the striatum expressed vimentin (VIM) and glial fibrillary acidic protein (GFAP) in the primary thick processes, aldehyde dehydrogenase 1 family member L1 (ALDH1L1) and S100 calcium-binding protein β (S100β) were additionally expressed in fine branchlets and leaflets. After toxin-induced denervation GFAP- and VIM-immunoreactivity showed the strongest activation of astrocytes, while astrocyte densities marked by ALDH1L1 and brain lipid binding protein (BLBP) were comparatively lower. In contrast, S100β-immunoreactivity did not present astrocyte activation. This study clearly illustrates that pathological changes of astrocytes occur to a great extent in the MFB 6-OHDA mouse model of PD. Astrocytes are a highly heterogeneous cell population, and different antibodies could possibly visualize different aspects of this intricate heterogeneity. Once peripheral inflammatory cells invade the brain, such MS foci often evolve into large lesions in the white but not in the gray matter, which could be due to the increased amount of myelin debris in the white matter. To support the hypothesis that a lower myelin content within the cortical gray matter could possibly limit lesion expansion, lysophosphatidylcholine (LPC) will be stereotactically injected into either the cortex or the white matter corpus callosum (CC) and lesion size and neuroinflammatory response will be compared following immunohistochemical approaches. Seven days after LPC injection a substantial proportion of the CC was demyelinated, whereas the extent of demyelination was by far less intense in the cortical region. Besides, increased demyelination of the CC was paralleled by an extensive microgliosis and a moderate astrocytosis, whereas both cellular parameters were less severe in the cortical gray matter. This implicates that local neuroinflammatory cascades, triggered by myelin debris, are pivotal factors for promoting lesion expansion in MS. Reasons underlying lesion development in MS remain largely elusive, however astrocytes appear to play a pivotal role. Morphological characterization of astrocytes could contribute to our understanding of cell type function, since differences in morphologies are believed to relate to the functional status. This study analyzed astrocyte morphology in the experimental cuprizone model of MS after activation of astrocytes by the innate immune system. GFAP+ astrocytes of the medial CC were 3D reconstructed within the Neurolucida 360 software and analyzed in the Neurolucida Explorer. The one-week cuprizone diet significantly increased the mean branch volumes. Besides, the average branch diameter was enlarged in distinct Shell radii compared to controls. In summary, the applied approach can examine morphological alterations of GFAP+ astrocytes.

Although kisspeptin and GPR54 have been reported to be expressed in the neurons of the dorsal root ganglion (DRG) of rats, and kisspeptin has been suggested to be involved in pain modulation in rodents, there is no study on the effects and mechanisms of kisspeptin on sensory neurons. Therefore, the aim of this study was to investigate the effects and mechanism of kisspeptin on intracellular free calcium levels in cultured rat DRG neurons. Bath application of kisspeptin-10 increased intracellular free calcium levels ([Ca2+]i). In the absence of extracellular calcium, the kisspeptin induced an attenuated but still significant increase in [Ca2+]i. [Ca2+]i responses persisted in the presence of protein kinase C (PKC) inhibitor. Data from this study revealed that kisspeptin-10 activates [Ca2+]i signaling independent of PKC in cultured rat sensory neurons suggesting that peripheral site is also involved in the pain modulating effect of kisspeptin.

Ian Hacking instigated a revolution in 20th century philosophy of science by putting experiments (“interventions”) at the top of a philosophical agenda that historically had focused nearly exclusively on representations (“theories”). In this paper, I focus on a set of conceptual tools Hacking (1992) put forward to understand how laboratory sciences become stable and to explain what such stability meant for the prospects of unity of science and kind discovery in experimental science. I first use Hacking’s tools to understand sources of instability and disunity in rodent behavioral neuroscience. I then use them to understand recent grass-roots collaborative initiatives aimed at establishing stability in this research area and tease out some implications for unity of science and kind creation and discovery in cognitive neuroscience.

Captive conditions differ widely from an animal’s natural environment and risk making them prone to reduced behavioural flexibility and sometimes impaired reproduction. The Patagonian mara Dolichotis patagonum, a near threatened species, is a large rodent endemic to Argentina with a singular social organisation that combines monogamy with communal breeding. The aim of this study was to learn more about the activity budget and behavioural synchrony between mates of zoo-housed D. patagonum and thus contribute to research and conservation programmes at modern zoos worldwide. The study implicated 28 animals housed at Cordoba Zoo (Argentina) under natural photoperiod and temperature conditions. Behaviour was recorded once a week every hour from 0800–1800 for a 28-day period and the total offspring at the end of the spring-summer season were counted. The recorded activity budget was: resting (43%), feeding (25%) and alert (13%), the remaining categories accounting for less than 10%. Resting, feeding and alert were the only categories associated with hourly changes. There was 48% behavioural synchrony between mates (both sexes engaging in the same behaviour at the same time) and a total of 23 offspring were counted, corresponding to one litter each reproducing female. The similarity between the behavioural response of these zoo-housed individuals and available data on the behaviour of D. patagonum in the wild indicates that zoo-housed D. patagonum behavioural activities can be considered positive responses, providing useful information for the future development of reintroduction programmes.

Atriyal natriüretik peptit (ANP) organizmanın sıvı homeostazında önemli etkileri olan, özellikle de kan basıncı ile sıvı elektrolit dengesinin düzenlenmesinde rol oynayan bir peptittir. Yoğun olarak atrial kalp kası hücrelerince üretilen ANP, merkezi sinir siteminde (MSS) lokalize bir grup nöron tarafından da eksprese edilir. MSS’de nöronal ağlarda impuls iletiminde çok önemli rolü olan glutamaterjik sistemin ANP nöronlarını kontrol eden etkileri ile ilgili bilgi literatürde yer almamaktadır. Sunulan çalışma kapsamında, hipotalamusun supraoptik çekirdeğinde lokalize ANP nöronları üzerinde glutamat agonistlerinin etkileri ve bu nöronlarda eksprese olan glutamat reseptör alt birimlerinin varlığı, ikili immünoperoksidaz ve immünoflouresans yöntemler kullanılarak araştırılmıştır. Glutamat agonistlerinin etkilerini belirlemek üzere, kainik asit, AMPA ve NMDA, kontrol grupları için salin, antagonist olarak CNQX ve MK801 enjeksiyonu yapılan sıçanları içeren deney grupları oluşturulmuştur. ANP nöronlarındaki glutamaterjik innervasyonun belirlenmesinde veziküler glutamat transporter (VGluT) proteinleri ve nöronal aktivasyonun gösterilmesinde ise c-Fos immünoreaktivitesinin varlığı belirteç olarak kullanılmıştır. Çalışmaların sonucunda; glutamat agonistlerinin ANP nöronlarında nöronal aktivasyonu anlamlı bir şekilde arttırdığı, bu artışın antagonistler ile anlamlı bir şekilde baskılanabildiği belirlenmiştir. Ayrıca ANP nöronlarının glutamat reseptörlerine ait alt birimlerden GluA1, GluA2, GluK1/2/3 ve GluK5’i eksprese ettikleri ve VGluT içeren glutamaterjik akson sonlanmalarıyla temasta oldukları saptanmıştır. Sonuç olarak, bu çalışma ile glutamatın ANP nöronlarında aktive edici etkiye sahip olduğu ve glutamat reseptörlerinin bu nöronlarca eksprese edildiği, dolayısıyla da bu nöronların glutamaterjik uyarıları alabilecek mekanizmaya sahip oldukları gösterilmiştir. Bu sonuçlar, ANP nöronlarının merkezi düzenlenmesinde glutamaterjik sistemin önemli bir rol oynayabileceğini düşündürmüştür.

The Allegheny woodrat (Neotoma magister) is a species of high conservation concern and relatively well-studied with respect to habitat use/associations, food habits, conservation genetics, and population trends. However, with the exception of raccoon roundworm (Baylisascaris procyonis) occurrence and etiology in woodrats, most disease and parasite ecology aspects for the woodrat are unknown. Herein, we examined the prevalence of bot flies (Cuterebra) over nearly three decades of woodrat surveys (1990–2018) in the central Appalachian Mountains of western Virginia. We use genetic analyses to identify recent bot fly specimen collections from a woodrat captured in 2017. Though highly variable from year to year, the overall prevalence of parasitism was low (typically < 4% of captures). As such, bot flies do not appear to be a widespread parasitic burden to Allegheny woodrats in Virginia. Genetic analysis of four collected bot fly larvae was inconclusive, as the genetic signature of these woodrat bots did not match any of the six bot species known to parasitize rodents and lagomorphs in the eastern United States. Further collections and genetic analyses will be needed to determine if the genetic database is incomplete or incorrect, or if our find is a new species of bot fly not yet taxonomically recognized.

Chemists re-engineer a psychedelic to treat depression and addiction in rodents

Hantavirus pulmonary syndrome is a zoonosis with a high fatality rate. Infection usually occurs by inhalation of aerosolized rodent secreta or excreta;

Dumpsites are an ideal breeding ground for disease vectors such as rats and mosquitoes, which may channel severe health issues to the nearby residents and dumpsite workers. The present study aimed to assess the effects of waste disposal at a dumpsite on the surrounding human settlements and health of the workers. In this descriptive study, data were collected from the households within the 0-3-kilometer radius to the dumpsite, as well as the dumpsite workers using structured questionnaires. In total, 150 respondents from the human settlements around the dumpsite participated in the study, including 61 dumpsite workers. Test of independence indicated a significant correlation between the perception of the dumpsite workers and community dwellers toward the dumpsite as a source of health-deteriorating agents (χ2 [1; n=211]=14.00; P=0.001). Dumpsite odor, insect and rodent infestation, and burning activities could predict the ill health status of the dumpsite workers with the final predictive model (ill health status=0.439 + [0.645*odor of dumpsite] + [0.106*insect and rodent infestation] + [-0.151*burning activities on dumpsite]; F[3,57]=21.70; P<0.05). According to the results, the human settlements in the vicinity of the dumpsite were discontented with the landfill and its adverse health effects (e.g., malaria, typhoid, skin infection). However, the dumpsite workers disagreed with the viewpoint regarding disease contraction from the dumpsite, stating that they were not dissatisfied with working on the dumpsite.

Feeding Experimentation Device version 3 (FED3): An open-source device for measuring food intake and motivation in rodents

Species composition, habitat association and altitudinal distribution of rodents and shrews were assessed in Chato Protected Area, Ethiopia, between July, 2015 and March, 2016. The area was stratified into five habitats based on dominant vegetation types and altitudinal zonation. The habitats were Carissa spinarum - Justicia schimperiana, Maytenus gracilipes, Podocarpus falcatus - Pyschotria orophila dominated habitats, riverine and plantation. A total of 254 small mammals comprising five rodent and one shrew species were live trapped from 1862 trap nights. The recorded rodent species were: Stenocephalemys albipes (40.95%), Lophuromys flavopunctatus (23.6%), Arvicanthis sp. (16.9%), Mus mahomet (13%), Mastomys natalensis (4.35%) and a shrew sp. (1.2%). Two of these rodent species (S. albipes and L. flavopunctatus) were the most abundant species that comprised 64.56% of the total; while Crocidura sp. was the least abundant distributed along the centre of the forest. M. gracilipes was dominant at 1,789 to 1,975 m, and was the most diverse habitat and comprised 19.39% of the trap success. P. falcatus- P. orophila was dominant from 1,975 to 2,230 m, and was diverse habitat that comprised 22.7% of the trap success. The plantation supported the least number of rodents. Key words: Altitudinal variation, Chato Protected Area, distribution, habitat, small mammals.

Animal carcasses provide an ephemeral pulse of nutrients for scavengers that use them. Carcass sites can increase species interactions and/or ephemeral, localized landscapes of fear for prey within the vicinity. Few studies have applied the landscape of fear to carcasses. Here, we use a mass die-off of reindeer caused by lightning in Norway to test whether rodents avoided larger scavengers (e.g. corvids and fox). We used the presence and abundance of faeces as a proxy for carcass use over the course of 2 years and found that rodents showed the strongest avoidance towards changes in raven abundance (<i>β =</i> −0.469, s.e. = 0.231, <i>p</i>-value = 0.0429), but not fox, presumably due to greater predation risk imposed by large droves of raven. Moreover, the emergence of rodent occurrence within the carcass area corresponded well with the disappearance of raven during the second year of the study. We suggest that carcasses have the potential to shape the landscape of fear for prey, but that the overall effects of carcasses on individual fitness and populations of species ultimately depend on the carcass regime, e.g. carcass size, count, and areal extent, frequency and the scavenger guild. We discuss conservation implications and how carcass provisioning and landscapes of fear could be potentially used to manage populations and ecosystems, but that there is a gap in understanding that must first be bridged.

Rodents in space: Keeping bone and muscle strong on the ISS

Rodents in space: Keeping bone and muscle strong on the ISS

Purpose: The larynx plays a role in swallowing, respiration, and voice production. All three functions change during ontogeny. We investigated ontogenetic shape changes using a mouse model to inform our understanding of how laryngeal form and function are integrated. We understand the characterization of developmental changes to larynx anatomy as a critical step toward using rodent models to study human vocal communication disorders.Method: Contrast-enhanced micro computed tomography image stacks were used to generate three-dimensional reconstructions of the CD-1 mouse (Mus musculus) laryngeal cartilaginous framework. Then, we quantified size and shape in four age groups: pups, weanlings, young, and old adults using a combination of landmark and linear morphometrics. We analyzed postnatal patterns of growth and shape in the laryngeal skeleton, as well as morphological integration among four laryngeal cartilages using geometric morphometric methods. Acoustic analysis of vocal patterns was employed to investigate morphological and functional integration.Results: Four cartilages scaled with negative allometry on body mass. Additionally, thyroid, arytenoid, and epiglottic cartilages, but not the cricoid cartilage, showed shape change associated with developmental age. A test for modularity between the four cartilages suggests greater independence of thyroid cartilage shape, hinting at the importance of embryological origin during postnatal development. Finally, mean fundamental frequency, but not fundamental frequency range, varied predictably with size.Conclusion: In a mouse model, the four main laryngeal cartilages do not develop uniformly throughout the first 12 months of life. High-dimensional shape analysis effectively quantified variation in shape across development and in relation to size, as well as clarifying patterns of covariation in shape among cartilages and possibly the ventral pouch.Supplemental Material S1. Methods.Riede, T., Coyne, M., Tafoya, B., & Baab, K. L. (2020). Postnatal development of the mouse larynx: Negative allometry age-dependent shape changes, morphological integration and a size-dependent spectral feature. Journal of Speech, Language, and Hearing Research. Advance online publication. https://doi.org/10.1044/2020_JSLHR-20-00070

Snake bite is a common problem in Nigeria and indeed in many parts of the world. [1] There seems to be a seasonal variation in the cases of snake bites that are reported. Although snake bite can happen anytime of the year, most reports are noted at the beginning of and during the period of rain. [2,3,4] This is when there is a significant change in the weather and the arrival of rain which fills the holes hence driving the snakes out and also for them to tap sun energy. During this time as well, farmers begin the usual farming season and hence increase in the risk of coming into contacts with several reptiles and rodents among which that with snakes has been noted to be the most dangerous of such encounters. [3] Snake bite can be fatal sometimes despite adequate attention but over the years there has been a decline in the mortality in some places due to prompt initiation of antivenom and other therapeutic measures including analgesics, antibiotics and tetanus toxoid. [2,5,6,7] However, it is of interest to note that it is not all such bites that are from snakes, it is not all bites from venomous snakes that results in envenomation needing the use of antivenom and by all means it is not all snakes that are venomous. [5] Antivenoms has been used from 20mls to 80mls to neutralise envenomation, there is paucity of data indicating the specific amount to be used in any condition of snake bites. [4,7,8] Dosages has been guided by the local and systemic indications for their usage and this may be confusing in rural areas. [8] More so that we have to use the same dosage regardless of the age of the patient since the amount of the venom injected into the host is the same considering the volume of distribution in children and adult or obese and the severely wasted individual. [7] Antivenoms whether monovalent or polyvalent are not entirely safe and sometimes anaphylaxis may happen despite adequate precaution. [6,8] Against this background, we tried to find a relationship between the clotting time done by the bedside and the volume of antivenom required by the patient. We tried to see if it could be possible to use the clotting time to predict the exact amount of the antivenom that will be required in cases of snake bite requiring envenomation. This we hoped may prevent the irregularity in the dosage of the antivenom and help standardize the use of antivenom in every hospital.

&lt;p class="awabstrak2"&gt;&lt;em&gt;Hantavirus&lt;/em&gt; is a zoonosis transmitted by rodents and have been spread in various countries. &lt;em&gt;Hantavirus&lt;/em&gt; causes &lt;em&gt;Hantavirus&lt;/em&gt; Pulmonary Syndrome (HPS) and Haemorrhagic Fever with Renal Syndrome (HFRS) in humans is still receiving worldwide attention due to the high case fatality rate. Epidemiological studies have shown that &lt;em&gt;Hantavirus&lt;/em&gt; is widespread globally, including in Indonesia. Indonesia is an archipelago and has a tropical climate, and is crossed by the equator so that it has an enormous diversity of animals, including those that become reservoirs of &lt;em&gt;Hantavirus&lt;/em&gt; and other vulnerable animals. The high risk of developing &lt;em&gt;Hantavirus&lt;/em&gt; in Indonesia does not rule out the possibility of a &lt;em&gt;Hantavirus&lt;/em&gt; outbreak if no preventive action is taken. Until now there is no effective and safe vaccine or treatment for &lt;em&gt;Hantavirus&lt;/em&gt;. Various development efforts continue to be made to obtain an appropriate and safe vaccine to prevent and stop the spread of &lt;em&gt;Hantavirus&lt;/em&gt;. This paper discusses &lt;em&gt;Hantavirus&lt;/em&gt;, including its structure and mechanism of transmission, the current situation of &lt;em&gt;Hantavirus&lt;/em&gt; in Indonesia and the efforts that can be made to prevent &lt;em&gt;Hantavirus&lt;/em&gt;, including the development of vaccines and their drugs.&lt;/p&gt;

Supplemental material, DS_10.1177_0363546520926471 for Zoledronic Acid Substantially Improves Bone Microarchitecture and Biomechanical Properties After Rotator Cuff Repair in a Rodent Chronic Defect Model by Jakob E. Schanda, Claudia Keibl, Patrick Heimel, Xavier Monforte, Stefan Tangl, Xaver Feichtinger, Andreas H. Teuschl, Andreas Baierl, Christian Muschitz, Heinz Redl, Christian Fialka and Rainer Mittermayr in The American Journal of Sports Medicine