Domestic Rats Research Articles

Characterization of Akabane virus from domestic bamboo rat, Southern China

To identify the causative agents in 3 large-scale outbreaks of encephalitis and death among farmed bamboo rats (Rhizomys pruinosus). The routine bacterial culture and identification were performed. There were no significant pathogenic bacteria isolated from the brain, heart, liver, spleen, lung, or kidney of diseased bamboo rats. Using PCR-based methods, we excluded the following as causative agent: pox virus, herpesvirus, adenovirus, lymphocytic choriomeningitis virus, rabies virus, and sendai virus. Furthermore, the homogenate from the diseased bamboo rats was subjected to viral metagenomic analysis which revealed 48506 filtered viral reads annotated to Akabane virus (AKAV) with >75% nucleotide identity, suggesting the presence of AKAVs in bamboo rats. Five novel AKAV isolates were successfully isolated and characterized. Furthermore the newly isolated AKAV isolate was used to demonstrate that it can reproduce the severe encephalitic and pneumonic disease in bamboo rats and mice. The findings add to the better understanding of AKAV epidemiology and to the prevention and control of Akabane diseases in China.

Clinical and Pathological Findings in 2 Rats (Rattus norvegicus) With Dilated Cardiomyopathy

Two 2-year-old intact female rats (Rattus norvegicus) were presented with severe dyspnea and tachypnea. In rat 1, radiographic evaluation of the thorax revealed severe pleural effusion, and cardiomegaly was suspected, suggesting a severe congestive heart failure. Echocardiography and computed tomography (CT) revealed bilateral pleural effusion, severe dilated cardiomyopathy (DCM), hepatomegaly, and mild abdominal effusion. Thoracocentesis and cytological examination revealed a chylous effusion. The patient was treated with a low-fat diet, octreotide, and medication to treat heart disease (furosemide, benazepril, pimobendan, and digoxin). However, because of worsening clinical signs, the animal was euthanized 5 days following the initiation of treatment. At necropsy, the heart was enlarged and rounded, with evident dilation of both ventricles, and the final diagnosis determined to be a DCM and myocardial fibrosis. The cardiac disease appeared to cause a chronic passive liver and lung congestion that, finally, resulted in both pleural and abdominal effusions. In rat 2, radiographic analysis of the thorax revealed pleural effusion and (conceivably) cardiomegaly, suggesting a severe congestive heart failure. Echocardiography and CT revealed pleural effusion and severe DCM of 4 chambers without effective contractility. Thoracocentesis was performed on the patient with the subsequent cytological examination of aspirated fluid being assessed as a transudate rich in macrophages and cells compatible with mastocytes. Cardiac medications were initiated, and the patient was monitored on a weekly basis. The rat died 27 days after the initial diagnosis due to respiratory failure. During the necropsy examination, it was determined that the rat’s heart was rounded, with enlargement of the left ventricle and thinning of the ventricular wall. The final disease diagnosis following the postmortem examination of rat 2 was a DCM and myocardial degeneration, which caused a chronic passive liver and lung congestion that resulted in a pleural effusion, hindering normal pulmonary activity. There is a paucity of published articles that describe DCM in rats. Recommended treatment of cardiovascular disease in this species is largely extrapolated from data obtained from cats, dogs, and ferrets. Further studies are warranted to detail the efficacy of therapeutic agents to treat cardiac disease in pet rats.

Mycoplasma pulmonisof Rodents as a Possible Human Pathogen

Mycoplasma pulmonis is a naturally occurring respiratory pathogen in rodents. To date, this pathogen was not isolated from humans. This study aimed to evaluate the prevalence and seropositivity to M. pulmonis in humans who have had direct contact with rats. Moreover, the prevalence of M. pulmonis in pet and laboratory rats was assessed. Overall, 131 and 235 oropharyngeal swab samples were collected from human individuals and rats, respectively. In humans, M. pulmonis was detected by PCR in 21 of 86 pet rat keepers (24.42%), 10 of 13 technicians (76.32%), and 8 of 32 (25.0%) veterinarians. In rats, M. pulmonis was identified by PCR in 86 of 122 pet rats (70.49%) and 56 of 113 (49.56%) laboratory rats. Seroprevalence in humans was examined by screening sera from 44 individuals for M. pulmonis-specific IgG using ELISA. In total, 26 out of 44 (59.09%) humans were seropositive to M. pulmonis (4 out of 9 technicians, 8 of 12 veterinarians, and 15 of 23 pet rat keepers).The high antibody titer was found in 4 individuals (2 pet rat keepers and 2 veterinarians), whereas the moderate and low antibody titers were found in 8 and 14 individuals, respectively. The high antibody titer found in humans might indicate an active infection. However, it is unknown whether the presence of M. pulmonis in humans might be associated with disease and whether the foreign Mycoplasma can survive for long in its new environment.

Bloodmeal Identification in Field-Collected Sand Flies From Casa Branca, Brazil, Using the Cytochrome b PCR Method.

PCR-based identification of vertebrate host bloodmeals has been performed on several vectors species with success. In the present study, we used a previously published PCR protocol followed by DNA sequencing based on primers designed from multiple alignments of the mitochondrial cytochrome b gene used to identify avian and mammalian hosts of various hematophagous vectors. The amplification of a fragment encoding a 359 bp sequence of the Cyt b gene yielded recognized amplification products in 192 female sand flies (53%), from a total of 362 females analyzed. In the study area of Casa Branca, Brazil, blood-engorged female sand flies such as Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1924), and Nyssomyia whitmani (Antunes & Coutinho, 1939) were analyzed for bloodmeal sources. The PCR-based method identified human, dog, chicken, and domestic rat blood sources.

Surgery and electrochemotherapy treatment of incompletely excised mammary carcinoma in two male pet rats (Rattus norvegicus).

Two male rats (Rattus norvegicus; 18 and 24 months old), were referred for treatment of large masses located in the axillary area. Following total body radiography and hematological and serum biochemical analysis, the rats were anesthetized, and the masses were surgically removed. Both lesions were diagnosed as mammary carcinoma based on histopathological diagnosis. The tumor beds were treated with two sessions of electrochemotherapy (ECT), two weeks apart. ECT involved cisplatin administration in the tumor bed, followed by a series of eight biphasic electric pulses. The treatment was well tolerated, and the rats were disease-free after 10 and 14 months. Therefore, adjuvant ECT resulted in good local control of mammary carcinoma and can potentially be used for adjuvant treatment of pet rats with cutaneous and adnexal tumors.

Origem e distribuição das principais artérias do membro torácico de Cuniculus paca (Linnaeus, 1766)

RESUMO: Objetivou-se descrever as artérias do membro torácico da paca (Cuniculos paca Linanaeus, 1766), mediante a dissecação da região. Para tanto, foram utilizadas 10 pacas adultas, machos ou fêmeas, pesando entre cinco e 10 kg do plantel de pacas do setor de Animais Silvestres da FCAV, Unesp, Jaboticabal-SP. Nos animais, injetou-se látex pela artéria carótida comum esquerda para preencher e corar todo o sistema arterial, seguido pela fixação em formaldeído a 10% e conservação em solução salina a 30% para dissecação anatômica das principais artérias do arco aórtico, braço e antebraço, identificando-se a origem e distribuição destes vasos. Os resultados foram foto documentados e discutidos com base na literatura sobre os animais domésticos, e roedores selvagens. De forma geral, as artérias do membro torácico da paca, assemelham-se com as dos carnívoros domésticos, do rato e da cobaia.

Reference intervals for biochemical blood variables, packed cell volume, and body temperature in pet rats (Rattus norvegicus) using point-of-care testing.

Rats (Rattus norvegicus) are increasingly kept as pets, thus more and more requiring veterinary care. Important differences exist between pet and laboratory rats, but little information is available on pet rats. Diagnosis and treatment of pet rat diseases would benefit from RIs specific for this animal population. The aim was to establish RIs for biochemical blood variables, PCV, and body temperature in pet rats. Additionally, influences of sex and feed rationing method (ad libitum, restricted) on these variables were determined. American Society for Veterinary Clinical Pathology (ASVCP) recommendations were followed. Biochemical variables were measured using an automated chemistry analyzer, the VetScan VS2. Nonparametric statistical methods were used to determine RIs and effects of sex and feed rationing method. Reference intervals were established using values of 123 clinically healthy pet rats (except for globulins and albumin/globulin ratio, n = 120) and were: glucose 6.6-13.7 mmol/L, total proteins 66-88 g/L, albumin ≥ 38 g/L, globulins 12-35 g/L, albumin/globulin ratio 1.0-4.7, urea nitrogen 2.5-6.6 mmol/L, creatinine ≤ 53 μmol/L, total bilirubin 4-7 μmol/L, ALP 40-442 IU/L, ALT 22-137 IU/L, amylase 502-1113 IU/L, sodium 133-144 mmol/L, potassium 3.6-5.3 mmol/L, calcium 9.5-10.9 mg/dL, phosphorus 2.3-7.0 mg/dL, PCV 40-50%, and body temperature 35.8-39.3°C. Sex significantly affected 10 variables. No significant influence was found with feed limitation CONCLUSIONS: Reference intervals reported in this study will be useful for interpretation of biochemistry analysis in pet rats and therefore improve pet rat medicine.

Risk factors for human Leptospira seropositivity in South Germany.

We analyzed risk factors for Leptospira seropositivity in humans, using data from a population-based cross-sectional zoonosis survey in South Germany (2008/9). Out of 1007 participants 42 (4.2 %) were sero-positive (19/446 men; 23/561 women), indicating that Leptospira exposure and sero-conversion is much more frequent than commonly assumed. Relative risks (RR) for seropositivity with exact 95 % confidence intervals (CI; adjusted for specificity and sensitivity of the ELISA test) were calculated for various exposure factors. Contact with pet rats (RR = 13.9 CI [4.8; 25.3]), guinea pigs (3.0[1.1; 7.4]), cattle (3.7[1.3; 9.6]), poultry (3.6[1.3; 8.6]) or livestock (2.3[1.1; 4.9]) as well as occupation as forestry worker (9.2[2.6; 21.4]) were identified as important exposure factors. None of the participants has ever been diagnosed with leptospirosis, yet 45 had experienced symptoms which may have been caused by Leptospira infection (12 with scleral icterus, 25 dark urine, 8 liver inflammation, 7 kidney failure). Three times as many participants with prior symptoms were seropositive as participants without symptoms (RR = 3.4[1.3; 8.3]), suggesting that sero-positive patients with severe symptoms may frequently not be diagnosed as leptospirosis cases. Physicians should consider leptospirosis as a differential diagnosis. Currently, the vast majority of symptomatic leptospirosis patients may neither be diagnosed nor reported.

Quantity Discrimination in Domestic Rats, Rattus norvegicus.

Simple SummaryQuantity discrimination involves distinguishing which of two quantities is greater. This discrimination between larger and smaller quantities has only been demonstrated in rats post extensive training. We tested whether domestic rats could perform quantity discrimination without explicit training. We found that rats could distinguish the greater amount in comparisons of 1 vs. 2, 2 vs. 3, 3 vs. 5, 3 vs. 8, 4 vs. 6, and 4 vs. 8. Rats could not distinguish between 3 vs. 4, 4 vs. 5 and 5 vs. 6. We also found that as the ratio between quantities became finer the choice of the larger quantity decreased. We conclude that rats can perform quantity discrimination without extensive training and that their quantity discrimination ability is influenced by the ratio between quantities.Quantity discrimination is a basic form of numerical competence where an animal distinguishes which of two amounts is greater in size. Whilst quantity discrimination in rats has been investigated via training paradigms, rats’ natural quantity discrimination abilities without explicit training for a desired response have not been explored. This study investigated domestic rats’ ability to perform quantity discrimination. Domestic rats (n = 12) were examined for their ability to distinguish the larger amount under nine quantity comparisons. One-sample t-tests identified a significant preference for the larger quantity in comparisons of 1 vs. 2, 2 vs. 3, 3 vs. 5, 3 vs. 8, 4 vs. 6, and 4 vs. 8. No preference between quantities was found for comparisons of 3 vs. 4, 4 vs. 5 and 5 vs. 6. Overall, this study drew two key conclusions. Firstly, that domestic rats are capable of performing quantity discrimination without extensive training. Secondly, as subjects adhered to Weber’s law, it was concluded that the approximate number system underpins domestic rats’ ability to perform spontaneous quantity discrimination.

Histopathological and Immunohistochemical Studies of Cowpox Virus Replication in a Three-Dimensional Skin Model

Human cowpox virus (CPXV) infections are rare, but can result in severe and sometimes fatal outcomes. The majority of recent cases were traced back to contacts with infected domestic cats or pet rats. The aim of the present study was to evaluate a three-dimensional (3D) skin model as a possible replacement for animal experiments. We monitored CPXV lesion formation, viral gene expression and cell cycle patterns after infection of 3D skin cultures with two CPXV strains of different pathogenic potential: a recent pet rat isolate (RatPox09) and the reference Brighton red strain. Infected 3D skin cultures exhibited histological alterations that were similar to those of mammal skin infections, but there were no differences in gene expression patterns and tissue damage between the two CPXV strains in the model system. In conclusion, 3D skin cultures reflect the development of pox lesions in the skin very well, but seem not to allow differentiation between more or less virulent virus strains, a distinction that is made possible by experimental infection in suitable animal models.

Gastrointestinal helminths and external parasites of domestic rats trapped from residential areas within Maiduguri Municipality, Nigeria

A survey of domestic rats was conducted to investigate the prevalence of gastrointestinal helminths and external parasites in Maiduguri municipal between February and June 2015. Rats were randomly collected from residential sites within Maiduguri metropolis by trapping using mechanical and glue board traps. Trapped rats were examined for external parasites, humanely sacrificed and subjected to detailed postmortem examination for recovery of gastrointestinal helminths using standard methods. Parasites were identified using key morphological characteristics. Out of 85 rats sampled in the study, a total of 7(8.2%) were positive for gastrointestinal helminths. The only species of helminth identified was Hymenolepis diminuta. There was no significant difference in prevalence of gastrointestinal helminths among different age groups and sexes (P>0.05). The overall prevalence of ectoparasites was 9.4% and there was no significant difference in prevalence rates among different age groups and sexes (P>0.05). The prevalence of flea (5.9%) was higher than lice (3.5%). The two species of ectoparasites identified in the study were Ctenocephalides canis (5.9%) and Polyplax spinulosa (3.5%). It was concluded from this study that domestic rats trapped from Maiduguri harbor some species of endoparasites and ectoparasites which are potentially zoonotic or may serve as vectors of important zoonotic pathogens.Keywords: Domestic rats, Ecto-parasites, Gastrointestinal helminths, Maiduguri, Prevalence

Kidney Measures in the Domestic Rat: A Radiographic Study and a Comparison to Ultrasonographic Reference Values

A total of 40 healthy pet rats (Rattus norvegicus) were used to determine normal radiographic kidney size and to compare radiographic vs. ultrasonographic kidney measurements. Kidney length and width and length of the second lumbar vertebra were determined from survey ventrodorsal radiographic images. Kidney dimensions were also expressed as a ratio to the body length of second lumbar vertebra. Based on study results, the reference intervals for left kidney ratios were 2.39 to 3.85 and 1.21 to 2.51 for length and width, respectively. For the right kidney ratios, the reference intervals were 2.13 to 3.98 and 1.16 to 2.44 for length and width, respectively. Statistical analysis showed that for the left kidney, there was a significant difference between radiographic and ultrasonographic measures for length and width (P = 0.0036 and P < 0.001, respectively). For the right kidney, there was a significant difference between radiographic and ultrasonographic measures for width (P = 0.0017) only. As apparent differences between ultrasonographic and radiographic measurements were minor, the radiographic and ultrasonographic measurements could potentially be used interchangeably for the rat kidney.

Zymbal Gland (Auditory Sebaceous Gland) Carcinoma Presenting as Otitis Externa in a Pet Rat (Rattus norvegicus)

A 1-year-old sexually intact male fancy rat (Rattus norvegicus) was presented for unilateral purulent otitis externa and weight loss. A small amount of bloody discharge was noted at the ostium of the left ear canal. The canal and the surrounding tissue were firm to the touch. Mild left-sided enophthalmos and facial nerve paralysis were noted. Otoscopic examination demonstrated caseous debris, and a swab of the external ear canal demonstrated a mixed population of rods and cocci on cytological evaluation. Bacterial culture of the external ear canal grew Escherichia coli. The rat was initially placed on oral and topical antimicrobial therapy. Despite treatment, the condition of the affected ear deteriorated and the rat continued to lose weight. Other clinical signs observed at this time included a worsening of the facial nerve paralysis, head tilt, and circling. A biopsy sample of the swollen tissue surrounding the left ear canal was collected; however, the rat died the day following the biopsy procedure. Histopathology of the biopsied tissue revealed an invasive neoplasm consistent with a Zymbal gland (auditory sebaceous gland) carcinoma. Zymbal glands are modified sebaceous glands surrounding the ear canal of rodents. Although chemically induced neoplasia of these glands is frequently observed, spontaneous tumor formation is much less common. Tumors of the Zymbal gland should be considered as underlying causes for unilateral otitis externa in rats.

Small Mammalian Remains from the Late Holocene Deposits on Ishigaki and Yonaguni Islands, Southwestern Japan.

Yuichiro Nishioka, Ryohei Nakagawa, Shin Nunami, and Satoshi Hirasawa (2016) Small mammalian remains were newly discovered from the Late Quaternary sediments of the Yaeyama region (Ishigaki and Yonaguni Islands) in the southwestern-most part of Japan. We examined these materials based on taxonomical and chronological approaches, in order to reconstruct the past fauna in this region. Accelerator Mass Spectrometry radiocarbon dating indicates that the mammalian assemblages from Ishigaki and Yonaguni Islands are composed mainly of late Holocene fossils. The fossil assemblage from Ishigaki Island comprises five species of small mammals belonging to Soricomorpha (Suncus murinus), Chiroptera (Pteropus sp., Hipposideros turpis, and Rhinolophus perditus), and Rodentia (Niviventer sp.). One rodent bone, collected from the fissure sediments near Sabichi-do Cave, Ishigaki Island, is dated at 230 ± 20 yBP (ca. AD 1,700), and is considered part of the recent remain. Furthermore, the fossil assemblage from Umabana-zaki Fissure, on Yonaguni Island, is dated at 1,760 ± 20 yBP (ca. AD 300) and comprises three species of small mammals belonging to Chiroptera (Pipistrellus cf. abramus) and Rodentia (Niviventer sp. and Mus musculus). Niviventer is not currently distributed in Japan. Only domestic rats (Rattus rattus and R. norvegicus) live on Ishigaki and Yonaguni Islands at the present time. However, the fossil assemblage from Umabana-zaki Fissure is dominated completely by Niviventer sp. Most fossils of small mammals found from the late Holocene Ishigaki and Yonaguni Islands represented species that are currently endemic to the Yaeyama region. Niviventer sp. from these islands is unique because this form has never been found from neighboring regions, such as Taiwan and Miyako Islands, and because it likely existed in the late Holocene. These discoveries support the hypothesis that the Yaeyama region had been isolated zoogeographically from the continent even during the Last Glacial Maximum, when the sea level had drastically fallen.

Miologia do membro torácico da paca (Cuniculus paca)

Resumo: Objetivou-se descrever os músculos do membro torácico da paca (Cuniculus paca Linnaeus, 1766), mediante dissecação anatômica dessa região. Foram utilizadas cinco Cuniculus paca adultas, machos e fêmeas, pesando entre cinco e 10kg do plantel de pacas do setor de Animais Silvestres da FCAV, Unesp, Jaboticabal/SP. Os animais foram fixados em formoldeído a 10% e conservados em solução salina a 30% para dissecação anatômica da musculatura do ombro, braço e antebraço, identificando-se a origem e inserção de cada músculo. Os resultados foram fotodocumentados e discutidos com base na literatura sobre animais domésticos, ratos e cobaias. Salvo algumas variâncias na origem e inserção de cada músculo e na fusão dos ventres de alguns grupos musculares, de forma geral, a musculatura do ombro, braço e antebraço da paca assemelha-se a dos animais domésticos e a de outros roedores.

Study on the Ectoparasites and Haemoparasites of Domestic Rats in Parts of Akure South Local Government Area of Ondo State

Study on the Ectoparasites and Haemoparasites of Domestic Rats in Parts of Akure South Local Government Area of Ondo State

Miologia do membro pélvico da paca (Cuniculus paca Linnaeus, 1766)

Resumo: Objetivam-se descrever os músculos do membro pélvico da paca (Cuniculus paca Linnaeus, 1766), mediante dissecção anatômica dessa região. Foram utilizadas dez Cuniculus paca adultas, machos e fêmeas, pesando entre cinco e 10 kg do plantel de pacas do setor de Animais Silvestres da FCAV, Unesp, Jaboticabal/SP. Os animais foram fixados em formaldeído 10% e conservados em solução salina a 30% para dissecação anatômica da musculatura da pelve, coxa e perna, identificando-se a origem e inserção de cada músculo. Os resultados foram fotodocumentados e discutidos com base na literatura sobre animais domésticos, ratos e cobaias. Salvo algumas variâncias na origem e inserção de cada músculo e na fusão dos ventres de alguns grupos musculares, de forma geral, a musculatura da paca assemelha-se a dos animais domésticos e a de outros roedores.

Atopic dermatitis-like skin lesions with IgE hyperproduction and pruritus in KFRS4/Kyo rats

BackgroundRats showing spontaneous atopic dermatitis (AD)-like skin lesions were observed in the Kyoto Fancy Rat Stock 4 (KFRS4) strain breeding colony. ObjectiveTo establish the KFRS4 rat as a model of AD. MethodsThe clinical symptoms of AD-like skin lesions were assessed by scoring the degree of dermatitis and examining scratching behavior. The transepidermal water loss was measured to evaluate skin barrier function. Cells infiltrating the skin lesions were identified using histological and immunohistological analyses. IgE and cytokine levels were measured to examine immune status. An ointment treatment experiment was carried out to characterize dermatitis in the KFRS4 rats. ResultsDermatitis initially appeared around 4 months of age and rapidly worsened from 6 to 8 months of age. The skin lesions accompanied scratching behavior and were predominantly observed in females. The increased transepidermal water loss indicated skin barrier dysfunction. Extensive infiltration of eosinophils, mast cells and lymphocytes was observed in the skin lesions. The plasma IgE level increased in accord with increasing severity of dermatitis. The Th2 and Th17 cytokine mRNA levels were significantly higher in the skin-draining lymph nodes than those in the non-skin-draining lymph nodes. It was demonstrated that betamethasone improved the symptoms of dermatitis. These findings demonstrated that dermatitis in the KFRS4 rats closely resembled that seen in human AD. ConclusionFemale KFRS4 rats have the potential to serve as an animal model of human AD.

SEROPREVALENSI LEPTOSPIRA PADA RATTUS NORvEgICUS DAN RATTUS TANEzUmI BERDASARKAN JENIS KELAMIN DAN UMUR

Rats are the main natural infectious host of leptospirosis to human. Rattus norvegicus (rats) and Rattus tanezumi (house mice) are two types of domestic rats that related with leptospira infection in the world. They are played the main role major leptospirosis transmission to human than others. This study aims to determine seroprevalence of Leptospira of R. norvegicus and R. tanezumi based of the sex and age. The method of study was trapping rats in the Miroto village (Semarang) and Tridonorejo village (Demak). LeptoTec Dri-Dot test has used after take blood of the rats intracardially and weight eye lens used to determinan age of the rats. The results showed seroprevalence of Leptospira in R. norvegicus were 66,67% and R. tanezumi were 24,39%. Seroprevalence of Leptospira in R. norvegicus females were 71,43% and R. norvegicus males were 60%. Seroprevalence of Leptospira in R. tanezumi females were 21,43% and R. tanezumi male were 30,77%. Based of age showed seroprevalence of Leptospira was highest in R. norvegicus and R.tanezumi adult than R. norvegicus and R. tanezumi young.

Out of the Reservoir: Phenotypic and Genotypic Characterization of a Novel Cowpox Virus Isolated from a Common Vole.

The incidence of human cowpox virus (CPXV) infections has increased significantly in recent years. Serological surveys have suggested wild rodents as the main CPXV reservoir. We characterized a CPXV isolated during a large-scale screening from a feral common vole. A comparison of the full-length DNA sequence of this CPXV strain with a highly virulent pet rat CPXV isolate showed a sequence identity of 96%, including a large additional open reading frame (ORF) of about 6,000 nucleotides which is absent in the reference CPXV strain Brighton Red. Electron microscopy analysis demonstrated that the vole isolate, in contrast to the rat strain, forms A-type inclusion (ATI) bodies with incorporated virions, consistent with the presence of complete ati and p4c genes. Experimental infections showed that the vole CPXV strain caused only mild clinical symptoms in its natural host, while all rats developed severe respiratory symptoms followed by a systemic rash. In contrast, common voles infected with a high dose of the rat CPXV showed severe signs of respiratory disease but no skin lesions, whereas infection with a low dose led to virus excretion with only mild clinical signs. We concluded that the common vole is susceptible to infection with different CPXV strains. The spectrum ranges from well-adapted viruses causing limited clinical symptoms to highly virulent strains causing severe respiratory symptoms. In addition, the low pathogenicity of the vole isolate in its eponymous host suggests a role of common voles as a major CPXV reservoir, and future research will focus on the correlation between viral genotype and phenotype/pathotype in accidental and reservoir species. We report on the first detection and isolation of CPXV from a putative reservoir host, which enables comparative analyses to understand the infection cycle of these zoonotic orthopox viruses and the relevant genes involved. In vitro studies, including whole-genome sequencing as well as in vivo experiments using the Wistar rat model and the vole reservoir host allowed us to establish links between genomic sequences and the in vivo properties (virulence) of the novel vole isolate in comparison to those of a recent zoonotic CPXV isolated from pet rats in 2009. Furthermore, the role of genes present only in a reservoir isolate can now be further analyzed. These studies therefore allow unique insights and conclusions about the role of the rodent reservoir in CPXV epidemiology and transmission and about the zoonotic threat that these viruses represent.