Impact of fertility versus mortality control on the demographics of Mastomys natalensis in maize fields

AbstractCercarial emission of schistosomes is a determinant in the transmission to the definitive host and constitutes a good marker to identify which definitive host is responsible for transmission, mainly in introgressive hybridization situations. Our goal was to test the hypothesis that micro-mammals play a role in Schistosoma haematobium, S. bovis, and/or S. haematobium x S. bovis transmission. Small mammal sampling was conducted in seven semi-lacustrine villages of southern Benin. Among the 62 animals trapped, 50 individuals were investigated for Schistosoma adults and eggs: 37 Rattus rattus, 3 Rattus norvegicus, 9 Mastomys natalensis, and 1 Crocidura olivieri. Schistosoma adults were found in four R. rattus and two M. natalensis, with a local prevalence reaching 80% and 50%, respectively. Two cercarial chronotypes were found from Bulinus globosus experimentally infected with miracidia extracted from naturally infected M. natalensis: a late diurnal and nocturnal chronotype, and an early diurnal, late diurnal, and nocturnal chronotype. The cytochrome C oxidase subunit I mtDNA gene of the collected schistosomes (adults, miracidia, and cercariae) belonged to the S. bovis clade. Eleven internal transcribed spacer rDNA profiles were found; four belonged to S. bovis and seven to S. haematobium x S. bovis. These molecular results together with the observed multi-peak chronotypes add M. natalensis as a new host implicated in S. haematobium x S. bovis transmission. We discuss the origin of the new chronotypes which have become more complex with the appearance of several peaks in a 24-h day. We also discuss how the new populations of offspring may optimize intra-host ecological niche, host spectrum, and transmission time period.

Download Full-text

Experimental Morogoro Virus Infection in Its Natural Host, Mastomys natalensis

Viruses ◽

10.3390/v13050851 ◽

2021 ◽

Vol 13 (5) ◽

pp. 851

Author(s):

Chris Hoffmann ◽

Stephanie Wurr ◽

Elisa Pallasch ◽

Sabrina Bockholt ◽

Toni Rieger ◽

...

Keyword(s):

Persistent Infection ◽

Virus Transmission ◽

Host Population ◽

Natural Host ◽

Lassa Virus ◽

Mastomys Natalensis ◽

Natural Hosts ◽

History Of ◽

Morogoro Virus ◽

The Impact

Natural hosts of most arenaviruses are rodents. The human-pathogenic Lassa virus and several non-pathogenic arenaviruses such as Morogoro virus (MORV) share the same host species, namely Mastomys natalensis (M. natalensis). In this study, we investigated the history of infection and virus transmission within the natural host population. To this end, we infected M. natalensis at different ages with MORV and measured the health status of the animals, virus load in blood and organs, the development of virus-specific antibodies, and the ability of the infected individuals to transmit the virus. To explore the impact of the lack of evolutionary virus–host adaptation, experiments were also conducted with Mobala virus (MOBV), which does not share M. natalensis as a natural host. Animals infected with MORV up to two weeks after birth developed persistent infection, seroconverted and were able to transmit the virus horizontally. Animals older than two weeks at the time of infection rapidly cleared the virus. In contrast, MOBV-infected neonates neither developed persistent infection nor were able to transmit the virus. In conclusion, we demonstrate that MORV is able to develop persistent infection in its natural host, but only after inoculation shortly after birth. A related arenavirus that is not evolutionarily adapted to M. natalensis is not able to establish persistent infection. Persistently infected animals appear to be important to maintain virus transmission within the host population.

Download Full-text

Hematologic and serum biochemistry reference intervals using defined ASCVP methodology for laboratory natal multimammate mice (Mastomys natalensis)

Laboratory Animals ◽

10.1177/00236772211018587 ◽

2021 ◽

pp. 002367722110185

Author(s):

Brian J Smith ◽

Patrick W Hanley ◽

Ousmane Maiga ◽

Maarit N Culbert ◽

Marissa J Woods ◽

...

Keyword(s):

Complete Blood Count ◽

Age Groups ◽

Serum Biochemistry ◽

Reference Intervals ◽

Laboratory Research ◽

Data Sets ◽

Mastomys Natalensis ◽

Complete Blood Counts ◽

Multimammate Mice ◽

Female Laboratory

Complete blood count, serum chemistry values, and biological reference intervals were compared between two age groups (34–49 and 84–120 days old) of healthy male and female laboratory raised natal multimammate mice ( Mastomys natalensis). Blood was collected via cardiocentesis under isoflurane anesthesia. Data sets of machine automated complete blood counts and clinical chemistries were analyzed. Significant differences between sex and age groups of the data sets were defined. The baseline hematologic and serum biochemistry values described here can improve interpretation of laboratory research using natal multimammate mice.

Download Full-text

Degenerative joint disease in Praomys (Mastomys) natalensis.

Annals of the Rheumatic Diseases ◽

10.1136/ard.26.2.146 ◽

1967 ◽

Vol 26 (2) ◽

pp. 146-154 ◽

Cited By ~ 14

Author(s):

L Sokoloff ◽

K C Snell ◽

H L Stewart

Keyword(s):

Degenerative Joint Disease ◽

Joint Disease ◽

Mastomys Natalensis

Download Full-text

Immunofluorescence studies on the association between a C-type oncornavirus and renal glomerulopathy in Praomys (Mastomys) natalensis

Clinical Immunology and Immunopathology ◽

10.1016/0090-1229(76)90154-9 ◽

1976 ◽

Vol 5 (1) ◽

pp. 105-118 ◽

Cited By ~ 4

Author(s):

Frida G. van Pelt ◽

P. Bentvelzen ◽

J. Brinkhof ◽

A.H. 't Mannetje ◽

C. Zurcher

Keyword(s):

Mastomys Natalensis ◽

Immunofluorescence Studies

Download Full-text

Global expression analysis of ECL cells in Mastomys natalensis gastric mucosa identifies alterations in the AP-1 pathway induced by gastrin-mediated transformation

Physiological Genomics ◽

10.1152/physiolgenomics.00216.2003 ◽

2004 ◽

Vol 20 (1) ◽

pp. 131-142 ◽

Cited By ~ 20

Author(s):

M. Kidd ◽

T. Hinoue ◽

G. Eick ◽

K. D. Lye ◽

S. M. Mane ◽

...

Keyword(s):

Gene Expression ◽

Gastric Mucosa ◽

Western Blot ◽

Cell Transformation ◽

Mastomys Natalensis ◽

Rt Pcr ◽

Cell Hyperplasia ◽

Ecl Cells ◽

Ecl Cell ◽

Gene Expression Alterations

Enterochromaffin-like (ECL) cell hyperplasia and then irreversible neoplasia can be generated in the African rodent Mastomys natalensis using the H2 receptor blocker, loxtidine, for 8–16 wk. We used a GeneChip approach complemented by standard technologies to identify gene expression alterations in the gastric mucosa during gastrin-mediated ECL cell transformation. Gastric mucosa (mucosal scrapping) and ECL cell-enriched fractions were obtained from untreated Mastomys (controls) and from animals treated with loxtidine for 8 wk (hyperplasia). Tumor ECL cells were obtained by hand-dissection of gastric ECL cell nodules from animals treated with loxtidine for >16 wk and from a spontaneously developed ECL cell tumor. RNA was isolated, examined on rat U34A GeneChips, and comparison analysis was performed to identify altered gene expression. Alterations in gene expressions were examined further by immunohistochemistry, quantitative RT-PCR (Q-RT-PCR), sequencing and Western blot. GeneSpring analysis demonstrated alterations in few genes (<20) in hyperplastic and tumor mucosa. The histamine H1 receptor was consistently increased in proliferating mucosa. This gene change was confirmed by Q-RT-PCR. Other genes showing alterations included neural-(chromogranin A and somatostatin), cell-cycle-, and AP-1-associated genes. Immunostaining confirmed alterations in neural markers. Cluster analysis of ECL cell-enriched samples demonstrated that c- fos and junD were differently regulated. Q-RT-PCR and Western blot in prospectively collected gastric mucosal samples confirmed the differential expression of Fos and Jun. The negative regulators of AP-1, JunD, and Menin were decreased in tumor mucosa. A missense of unknown function was noted in the menin gene. Hypergastrinemia in an animal model of gastric carcinoids differentially altered the histamine type 1 receptor and gene expression and protein composition of AP-1. These results suggest that expression of this receptor and an altered composition of AP-1 with a loss of inhibition play a role in ECL cell transformation.

Download Full-text