scholarly journals Effect of gonadotrophins on the ovarian interstitial tissue of the wood mouse, Apodemus sylvaticus

Reproduction ◽  
2001 ◽  
pp. 123-129 ◽  
Author(s):  
J Clarke ◽  
F Brook

The ovarian interstitial tissue of the wood mouse (Apodemus sylvaticus) is extensively developed. The effect of equine chorionic gonadotrophin (eCG) and human chorionic gonadotrophin (hCG) on ovarian interstitial tissue was investigated in wood mice from a laboratory stock. The tissue was assessed by measuring the relative size of the cells, cell nucleus diameter and (in adults) nuclear shape. Hormone-treated wood mice had larger interstitial cells and larger cell nuclei than untreated animals. In addition, the cell nuclei of adult hormone-treated wood mice had a smooth round or oval outline, whereas those of untreated animals had an irregular outline with spiky projections. Electron microscopy showed that the irregular spiky outline of the cell nuclei in untreated wood mice was caused by distortions of the nuclear membrane by a large number of intracellular lipid droplets; the droplets were less abundant in the hormone-treated animals. These experiments indicate that the cells of the interstitial tissue of the wood mouse are under the control of gonadotrophins, and that these cells are likely to be a site of the synthesis and release of steroid hormones. The methods used in this study to assess the state of the cells could be applied to animals from the field to investigate the role of interstitial tissue in the reproductive biology of wood mice.

2020 ◽  
Vol 8 (3) ◽  
pp. 374
Author(s):  
Lucía Varela-Castro ◽  
Olalla Torrontegi ◽  
Iker A. Sevilla ◽  
Marta Barral

Mycobacterial infections caused by the Mycobacterium tuberculosis complex (MTC) and non-tuberculous mycobacteria (NTM) are of great medical and veterinary relevance. The aim of this research was to study whether small mammals play a role in the epidemiology of mycobacterioses. Four samplings of 100 traps were performed in each of three cattle farms with previous history of tuberculosis or NTM between 2017 and 2018. A total of 108 animals belonging to seven species were trapped, classified, and necropsied, and tissues were submitted to microbiological and molecular methods for mycobacteria identification. The wood mouse (Apodemus sylvaticus) was the most abundant species (87%). No MTC was detected but six different NTM were identified (M. intracellulare, M. avium subsp. paratuberculosis, M. gordonae, M. celatum, M. fortuitum, and a not determined Mycobacterium sp.), showing a prevalence of 6.5%. No significant association was found between mycobacteria prevalence and the analyzed factors. Although a role in the epidemiology of MTC could not be attributed to small mammals, A. sylvaticus carries NTM that could be pathogenic or interfere with the diagnosis of tuberculosis. According to our results, there is a risk of NTM transmission at the wildlife–livestock interface through potential indirect contacts between small mammals and cattle.


Parasitology ◽  
2002 ◽  
Vol 124 (2) ◽  
pp. 185-190 ◽  
Author(s):  
H. A. NOYES ◽  
P. AMBROSE ◽  
F. BARKER ◽  
M. BEGON ◽  
M. BENNET ◽  
...  

The strongest evidence for host specificity of mammalian trypanosomes comes from parasites of the subgenus Trypanosoma (Herpetosoma). Laboratory studies have shown that T. (Herpetosoma) species will not infect an alternative host. However, this has not been demonstrated in wild populations. We screened 560 bank voles (Clethrionomys glareolus) and 148 wood mice (Apodemus sylvaticus) for trypanosomes by PCR amplification of the 18S rRNA gene. In total, 109 (19%) bank voles and 12 (8%) wood mice were infected. A HaeIII restriction site was discovered that could be used to discriminate between T. (H.) evotomys of the bank vole and T. (H.) grosi of the wood mouse. All the parasites in the bank voles were identified as T. (Herpetosoma) evotomys by RFLP-PCR. Out of the 12 wood mouse infections 10 were due to T. grosi. Two of the wood mice were infected with parasites with a novel genotype that was most similar to those of T. evotomys and T. microti of voles. Fifty-six fleas collected from the rodents were also screened for trypanosomes; 9 were infected with T. evotomys and 1 with T. grosi. One of the fleas infected with T. evotomys was collected from a wood mouse.


2014 ◽  
Vol 59 (4) ◽  
Author(s):  
Ángela Debenedetti ◽  
Sandra Sáez-Durán ◽  
Sandra Sainz-Elipe ◽  
Maria Galán-Puchades ◽  
Màrius Fuentes

AbstractAonchotheca annulosa and Eucoleus bacillatus are two capillariin nematodes parasitizing the intestinal and stomach mucosa, respectively, of various rodent species, and two, among others, component species of the helminth fauna of the wood mouse, Apodemus sylvaticus. A capillariin each was found in the liver parenchyma of two wood mice in a post-fire regeneration enclave in Serra Calderona Natural Park (Valencian Community, Spain). Due to their location, the preliminary identification of the helminths corresponded to Calodium hepaticum, a hepatic capillariin with rodents as its main host. So far, this species had never been found in Serra Calderona. To verify the preliminary identification, a comparative morphometric study between the specimens from Serra Calderona and a preserved individual of C. hepaticum from another enclave was carried out. Morphometric analysis revealed that the adult helminth as well as the eggs found in the liver of the first mouse belonged to A. annulosa, whereas the second one was identified as a male E. bacillatus. Moreover, the liver from both hosts showed a visible pathology, being the consequence of aberrant migration of the parasites. This is the first evidence that A. annulosa and E. bacillatus may migrate erratically and thus produce ectopic foci in other organs.


2013 ◽  
Vol 91 (2) ◽  
pp. 102-109 ◽  
Author(s):  
Sarah Bauduin ◽  
Jacques Cassaing ◽  
Moussa Issam ◽  
Céline Martin

Extensive niche overlap between closely related species generally leads to aggressive interactions and competition. The short-tailed mouse (Mus spretus Lataste, 1883) and the wood mouse (Apodemus sylvaticus (L., 1758)) show a large habitat overlap without aggressive interactions. The present study investigates the existence of food competition between these species, based on an analysis of carbon and nitrogen stable isotopes. An almost exhaustive sample of plants, which were potential food resources, was taken and analyzed to infer the consumed plants in mouse diets. The main result showed that both species had a similar diet composition, consisting exclusively of seeds and fruits. This suggests that no competition for food between these species is apparent, or if it exists it would be minimized by a differential exploitation of resources. In the absence of food and space competition,the short-tailed mouse may be using the presence of the wood mouse as an indicator of habitat food quality. In the case of wood mice, we hypothesize that the level of competition with short-tailed mice may be low because of the abundance of resources and because the wood mice may perceive the smaller short-tailed mouse as being equivalent to a young of their own species.


2021 ◽  
Vol 95 ◽  
Author(s):  
J.W. Lewis ◽  
N.J. Morley ◽  
J.M. Behnke

Abstract The distributions of the nematode parasites Heligmosomoides polygyrus and Syphacia stroma were quantified in three equal-length sections along the intestine of wood mice (Apodemus sylvaticus) trapped in three different locations in the south of England. The distribution of H. polygyrus did not change in the presence of S. stroma, this species being largely confined to the anterior third of the intestine, whether S. stroma was or was not present. However, while in single infections with S. stroma, worms were equally distributed in the anterior and middle sections of the intestine, in the presence of H. polygyrus, a higher percentage of worms was located in the middle section. This was a dose-dependent response by S. stroma to increasing worm burdens with H. polygyrus, and even relatively low intensities of infection with H. polygyrus (e.g. ≤10 worms) were sufficient to cause a posterior redistribution of S. stroma into the middle section. A similar posterior shift in the percentage distribution of S. stroma in the intestine was evident in juvenile and mature mice of both sexes, and in mice from all three study sites. The ecological significance of these results is discussed.


Reproduction ◽  
1989 ◽  
Vol 85 (1) ◽  
pp. 251-260 ◽  
Author(s):  
F. A. Brook ◽  
J. R. Clarke

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Chun-Won Kang ◽  
Eun-Suk Jang ◽  
Nam-Ho Lee ◽  
Sang-Sik Jang ◽  
Min Lee

AbstractWe investigated the effect of ultrasonic treatment on Malas (Homalium foetidum) gas permeability and sound absorption coefficient using the transfer function method. Results showed a longitudinal average Darcy permeability constant of 2.02 (standard deviation SD 0.72) for untreated wood and 6.15 (SD 3.07) for ultrasound-treated wood, a permeability increase of 3.04 times. We also determined the average sound absorption coefficients in the range of 50 to 6.4 kHz and NRC (noise reduction coefficient: average value of sound absorption coefficient value at 250, 500, 1000, and 2000 Hz) of untreated Malas. Those values were 0.23 (SD 0.02) and 0.13 (SD 0.01), respectively, while those of ultrasonic-treated Malas were 0.28 (SD 0.02) and 0.14 (SD 0.02), a 19.74% increase in average sound absorption coefficient.


Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Lukas Emmerich ◽  
Maja Bleckmann ◽  
Sarah Strohbusch ◽  
Christian Brischke ◽  
Susanne Bollmus ◽  
...  

Abstract Chemical wood modification has been used to modify wood and improve its decay resistance. However, the mode of protective action is still not fully understood. Occasionally, outdoor products made from chemically modified timber (CMT) show internal decay while their outer shell remains intact. Hence, it was hypothesized that wood decay fungi may grow through CMT without losing their capability to degrade non-modified wood. This study aimed at developing a laboratory test set-up to investigate (1) whether decay fungi grow through CMT and (2) retain their ability to degrade non-modified wood. Acetylated and 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) treated wood were used in decay tests with modified ‘mantle specimens’ and untreated ‘core dowels’. It became evident that white rot (Trametes versicolor), brown rot (Coniophora puteana) and soft rot fungi can grow through CMT without losing their ability to degrade untreated wood. Consequently, full volume impregnation of wood with the modifying agent is required to achieve complete protection of wooden products. In decay tests with DMDHEU treated specimens, significant amounts of apparently non-fixated DMDHEU were translocated from modified mantle specimens to untreated wood cores. A diffusion-driven transport of nitrogen and DMDHEU seemed to be responsible for mass translocation during decay testing.


Sign in / Sign up

Export Citation Format

Share Document