Synanthropic rodent reservoirs of Trypanosoma (Schizotrypanum) cruzi in the valley of Caracas, Venezuela

Direct blood examination and xenodiagnosis of 47 synanthropic rodents (Rattus rattus, R. norvegicus, Mus musculus) captured in the valley of Caracas, Venezuela, revealed trypanosomal infections in 12 R. rattus, 10 with T. lewisi and 2 with T. cruzi. Of the latter the course of parasitemia, the pleomorphism of the bloodstream trypomastigotes, tissue tropism in naturally and experimentally infected rats and mice, host mortality, morphology of fecal parasites in Rhodnius prolixus used for xenodiagnosis, and infectivity of the bug feces for NMRI mice, were all characteristic of Trypanosoma (Schizotrypanum) cruzi. One rat, with a patent parasitemia, had numerous nests of amastigotes in cardiac muscle and moderate parasitism of the smooth muscle of the duodenum and of skeletal muscle. Mice inoculated with fecal flagellates from the bugs had moderate tissue tropism in the same organs and also in the colon and pancreas. The possible role of R. rattus in the establishment of foci of Chagas’ disease in Caracas is discussed

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Ticks on small mammals from an ecotone region impacted by rural activities in Brazil

Systematic and Applied Acarology ◽

10.11158/saa.26.2.7 ◽

2021 ◽

Vol 26 (2) ◽

pp. 427-437

Author(s):

Rafael Quirino Moreira ◽

Vanessa Do Nascimento Ramos ◽

Adriane Suzin ◽

Diego Garcia Ramirez ◽

Paulo Ricardo De Oliveira Roth ◽

...

Keyword(s):

Atlantic Forest ◽

Small Mammals ◽

Mus Musculus ◽

Tick Species ◽

Rattus Rattus ◽

Riparian Forests ◽

Forest Fragments ◽

Cerrado Biome ◽

Didelphis Albiventris

We evaluated the role of communities of small mammals from three distinct areas in a region of Cerrado mixed with Atlantic Forest remains for maintenance of tick fauna. Thirty-nine marsupials (Gracilinanus agilis, n = 34; Marmosa paraguaiana, n = 4; Didelphis albiventris, n = 1) and 33 rodents (Oecomys cleberi, n = 10; Nectomys squamipes, n = 4; Calomys tener, n = 4; Hylaeamys megacephalus, n = 4; Akodon sp., n = 3; Rattus rattus, n = 3; Cerradomys subflavus, n = 2; Mus musculus, n = 2; Rhipidomys macrurus, n = 1) were captured. Solely G. agilis and the four rodent species (N. squamipes, R. macrurus, C. subflavus and Akodon sp.) were infested. Four tick species were collected (Amblyomma dubitatum, Amblyomma sculptum, Ixodes loricatus and Ornithodoros mimon). A. dubitatum was the most abundant tick species on hosts. Capture success was higher in the dry season, but the infestation was similar in both seasons. Forested habitats, particularly riparian forests, resulted in higher number of hosts and ticks collected (from hosts and from vegetation), compared to pastures and anthropized sites. The association between C. subflavus and I. loricatus and between A. dubitatum and N. squamipes observed here is the first recorded in Cerrado biome. Areas with more patches of forest, including the Atlantic Forest fragments, tend to present a richest community of small mammals and associated ticks.

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Toxoplasma gondii and Neospora caninum infections in synanthropic rodents from Argentina

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612019009 ◽

2019 ◽

Vol 28 (1) ◽

pp. 113-118 ◽

Cited By ~ 1

Author(s):

Andrea Dellarupe ◽

Bruno Fitte ◽

Lais Pardini ◽

Lucía María Campero ◽

Mariana Bernstein ◽

...

Keyword(s):

Toxoplasma Gondii ◽

Neospora Caninum ◽

Rattus Rattus ◽

Wide Distribution ◽

Type I ◽

Type Ii ◽

Caninum Infection ◽

Coccidian Parasites ◽

Rats And Mice ◽

Synanthropic Rodents

Abstract Toxoplasma gondii and Neospora caninum are closely related coccidian parasites (phylum Apicomplexa). This is the first study from urban synanthropic rodent species that involved serological and molecular diagnosis of T. gondii and N. caninum infection, and genotyping of T. gondii in Argentina. A total of 127 rodent samples were trap captured: Mus musculus (n = 78), Rattus norvegicus (n = 26) and Rattus rattus (n = 23). Antibodies against T. gondii and N. caninum were detected by IFAT in 32.8% (40/122) and 0.8% (1/122) of rodent samples, respectively, demonstrating contact with these protozoans. Additionally, T. gondii DNA was detected in 3.3% (4/123) of rodent central nervous system samples and 2 samples were genotyped by multilocus nPCR-RFLP. Neospora caninum DNA was not detected by PCR. The 2 genotyped samples were type III allele for all markers except for SAG-1 (type I for Rat1Arg and type II/III for Rat2Arg) and were identified as #48 and #2 (likely) according to the allele combinations reported on Toxo DB (Toxo-DB). The results of the present study revealed a wide distribution of T. gondii and less for N. caninum, in synanthropic rats and mice in the studied area.

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The control of introduced Rattus rattus L. on Lord Howe Island. II. The status of warfarin resistance in rats and mice

Wildlife Research ◽

10.1071/wr99013 ◽

2000 ◽

Vol 27 (6) ◽

pp. 659 ◽

Cited By ~ 7

Author(s):

Justin Billing

Keyword(s):

Mus Musculus ◽

Rattus Rattus ◽

Untreated Group ◽

House Mice ◽

Lord Howe Island ◽

The Status ◽

Warfarin Resistance ◽

Rats And Mice ◽

Black Rats

Black rats (Rattus rattus) and house mice (Mus musculus) from Lord Howe Island were live-trapped, housed in the laboratory and tested for resistance to the anticoagulant poison warfarin. All rats fed warfarin (0.025% w/w) in their diet died within 4–12 days whereas no rats in the untreated group died. Mice fed warfarin at the same concentration over 21 days all survived. Black rats on Lord Howe Island remain susceptible to warfarin, but house mice appear resistant.

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Increased myogenic tone in skeletal muscle arterioles of diabetic rats. Possible role of increased activity of smooth muscle Ca2+ channels and protein kinase C

Cardiovascular Research ◽

10.1016/s0008-6363(99)00106-6 ◽

1999 ◽

Vol 43 (4) ◽

pp. 1018-1028 ◽

Cited By ~ 61

Author(s):

Z Ungvari

Keyword(s):

Skeletal Muscle ◽

Smooth Muscle ◽

Protein Kinase C ◽

Protein Kinase ◽

Diabetic Rats ◽

Myogenic Tone ◽

Kinase C ◽

Increased Activity ◽

Ca2 Channels

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Analysis of different factors contributing the rodent infestations in urban areas in Faisalabad, Pakistan

The Pakistan Journal of Agricultural Sciences ◽

10.21162/pakjas/21.132 ◽

2021 ◽

Vol 58 (04) ◽

pp. 1197-1203

Author(s):

Azhar Rafique

Keyword(s):

Mus Musculus ◽

Urban Areas ◽

Rattus Rattus ◽

Human Populations ◽

Low Grade ◽

Breeding Sites ◽

Housing Systems ◽

Building Maintenance ◽

Serious Disease ◽

Rats And Mice

In the last decade there is a huge increase in the human population that has witnessed the important changes in the ecology, climate and human behaviour which ultimately favours the survival and increase in the population of urban pests. More alarmingly, a dramatic expansion in the rodent’s populations is a growing threat to the humans living in different urban settings. It is supposed that several socio-economic issues, environmental factors and type of housing facilities are contributing towards this higher increase in the rodent’s population in these areas. However, urban rat control programs are still ineffective as very little is known about their ecology. This study sought to investigate the type of housing and environment factors that provide food, water, shelter and harborage to rats and mice and risk factors of rodent infestations in three of the housing systems i.e. in squatter’s settlements, departmental colonies and posh residences including bungalows in Faisalabad. A total of 720 structures (240 each) were selected from these three housing systems. Snap and live trapping of commensal rats and mice (Rattus rattus, Rattus norvegicus,Mus musculus) was carried out fortnightly from November, 2017 to October, 2018 suspecting the rats and mice population as variable as different structured housing systems. The removal data were used to estimate the size of the population of rats and mice per system. For rat and mice population estimation, Change-in-ratio (CIR) and Regression of daily capture on cumulative captures (RR) were employed. The higher number of rats/mice (814 specimens) were collected in squatter’ settlements. Among these 560, 184 and 70 specimens were of Mus musculus, Rattus rattus and Suncus murinus, respectively. The number of rodents captured from departmental colonies and posh residences/bungalows was 210 specimens (129 of M. musculus, 71 of R. rattus and 10 specimens of S. murinus) and 30 specimens of M. musculus, respectively. The major socio-economic factors contributing to these higher rodent infestations were low-grade residences with inadequate or no building maintenance measures and higher housing densities along with heterogenous breeding sites. These higher densities of rats and mice may pose a serious disease threats to human populations as they are carriers of a number of pathogens. The findings of the present study provide the specific features of rats and mice population in concern to human residences and may help to formulate controlling strategies against these culprits.

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Electron Probe Analysis of Muscle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054583 ◽

1982 ◽

Vol 40 ◽

pp. 398-401

Author(s):

A. V. Somlyo ◽

H. Shuman ◽

A. P. Somlyo

Keyword(s):

Skeletal Muscle ◽

Smooth Muscle ◽

Sarcoplasmic Reticulum ◽

Resting State ◽

Binding Sites ◽

Electron Probe ◽

Frog Skeletal Muscle ◽

Electron Probe Analysis ◽

Probe Analysis

Electron probe analysis of frozen dried cryosections of frog skeletal muscle, rabbit vascular smooth muscle and of isolated, hyperpermeab1 e rabbit cardiac myocytes has been used to determine the composition of the cytoplasm and organelles in the resting state as well as during contraction. The concentration of elements within the organelles reflects the permeabilities of the organelle membranes to the cytoplasmic ions as well as binding sites. The measurements of [Ca] in the sarcoplasmic reticulum (SR) and mitochondria at rest and during contraction, have direct bearing on their role as release and/or storage sites for Ca in situ.

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