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3. Coprophagy in Brandt's vole (Microtus brandti) from the Inner Mongolian grasslands

Creator:
Pei, Yan-Xin, Wang, De-Hua, Wand, Zu-Wang, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
Brandt's vole, Microtus brandti, and coprophagy
Language:
English
Description:
We studied coprophagous behaviour in Brandt's vole using a solute food marker (Co-EDTA). Examination of marker concentrations in the stomach, small intestine, caecum and colon of voles killed at half-hour intervals after a pulse dose of Co-EDTA indicated that the marker was recycled to the stomach by coprophagy. Recycling of digesta via coprophagy enables Brandt's vole to utilise diets of higher fibre contents. This is the first evidence for coprphagy in this species.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

4. distribution and breeding seasons of the dassie-rat, Petromus typicus (Petromuridae, Rodentia)

Creator:
Coetzee, Cornelius G., Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
desert adaptation, macroclimate, fecundity, embryos, placental scars, and tooth wear
Language:
English
Description:
The diurnal dassie-rat, Petromus typicus, occurs in the mountainous areas along the eastern side of the Namib Desert, as well as and on inselbergs in the Namib with an annual mean rainfall >25 mm. Its distribution is limited by the presence of either moist woodlands or to areas with cold, wet winters. The gestation period is taken as three months, based on the precocial condition of the young at birth. A maximum of three young per litter was recorded, with two being the mode. The young start taking solid food at 14 days and wean at about three weeks, then attaining adulthood at about nine months (at a mass of ca. 150 g). The two main breeding seasons could be related to the onset of the rainy season, although it cannot be ruled out that breeding in endogenous.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

5. Epigenetic and morphometric divergence among black rat, Rattus rattus, populations on Western European islands

Creator:
Sousa, Inês Pereira de, Quartau, José Alberto, Mathias, Maria da Luz, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
insularity, differentiation and variability, and colonisation
Language:
English
Description:
Over the decades, islands have provided a useful background for the evaluation of the consequences of isolation upon populations. Epigenetic and morphometric divergence among black rat (Rattus rattus) populations from Western European island (São Miguel, Terceira, Flores, Porto Santo, Berlenga, Corsica) were analysed and compared with mainland reference populations (Portugal, France, Morocco). Neither of the two approaches showed insular samples to have greater distinctiveness than those from the mainland. The overall pictures of epigenetic and morphometric similarity among populations were concordant, apparently in agreement with their probable origin from founder individuals brought by former maritime traffic. Mainland populations were more variable, but only according to morphometric characters. The adaptive and evolutionary significance of the patterns found may be related to both the period of population isolation and island area.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

6. First results of beaver (Castor fiber) reintroduction in Volga-Kama National Nature Zapovednik (Russia)

Creator:
Gorshkov, Yurii A., Gorshkov, Dmitry Y., Easter-Pilcher, Andrea L., Pilcher, Brian K., Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
feeding behaviour, home range size, radiotelemetry, food preference, and dispersal after reintroduction
Language:
English
Description:
The main reason for reitroducing beavers (Castor fiber) to the Raifa part of the Voga-Kama National Nature Zapovednik (VKNNZ) was to utilise their habitat-changing activities - primarily the use of their ability to build dams - to stop the degradation of the Zapovednik hydrosystem (Gorshkov et al. 1999). Today there are seven beaver dams on the rivers that run through the Zapovednik. We studied the movements of the beavers by locating new cuts, dens, trails, dams, etc. and by radiotelemetry. We assumed that in the first phase of reintroduction the spatial structure of the beaver subpopulation consisted of four permanent and five temporary settlements. We determined the home ranges of the reintroduced beavers as being approximately seven ha, plus smaller additional patches of habitat that were used during the witner. Another object of our investigation - the feeding behaviour of reintroduced beavers - showed that the most preferred tree genera were aspen and willows, followed by alder and birch. The wolume of trees cut by beavers between autumn 1996 and spring 1999 in the Volga-kama National Nature Zapovednik was 11.69 m3
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

7. Food selection of Microtus agrestic in air-pollution affected clearings in the Beskydy Mts, Czech Republic

Creator:
Heroldová, Marta, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
field vole, diet, air pollution clearings, and impact on forest regeneration
Language:
English
Description:
The small mammal community of an air pollution affected area of the Beskydy Mts was studied over a seven-year period. Highest dominance and population density values were found in the field vole (Microtus agrestis) and its feeding ecology and negative impact on reforestation have been evaluated. The vegetative parts of plants, particularly those of monocotyledons, were dominant in vole diets, mainly as the area is largely occupied by the invasive plant genus Calamagrostis. In early spring (i.e. before the growing season started) grasses predominated in the field vole's food (74 % of volume, v). Bark was also consumed to some extent - its importance index value (I) was 4 %. In spring (i.e. after the growing season started) grasslike species were again preferred (v = 57 %) but flowers of Vaccinium myrtillus were also consumed (v = 20 %). Even in autumn grasslike species prevailed (v = 36 %), however, the diet was more diverse and seeds and fruits (v = 30 %) were also eaten. of these the basic food items were those of V. myrtillus (v = 16 %) and of herbs and ferns (v = 16 %) including Oxalis acetosella (v = 14 %). An increase in fungi in the diet was found in autumn. Diet availability and early spring and spring diets ere highly correlated, but this was not the case in autumn. The extent of vole damage to tree regeneration in 3,027 saplings was studied. The frequency of damage was significantly greater in deciduous tree species (15 %). Coniferous tree transplants were attacked only rarely (1.4 %), and usually when the tree was already in poor condition. The greater degree of damage caused to natural and artificial forest regenetarion can only be associated with high vole population densities.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

8. Genetic relatedness discriminationin eusocial Cryptomys anselli mole-rats, Bathyergidae, Rodentia

Creator:
Heth, Giora, Todrank, Josephine, Begall, Sabine, Wegner, Regina E., and Burda, Hynek
Type:
article and TEXT
Subject:
recognition mechanisms, kin recognition, and individual odours
Language:
English
Description:
Previous research has demonstrated that, irrespective of prior familiarity, both social and solitary rodent species respond differentially to odours of other individuals based on the degree of genetic relatedness between them. To investigate whether eusocial species also make odour-based genetic relatedness discriminations, male and female Ansell’s mole-rats (Cryptomys anselli) were exposed to ano-genital odours of unfamiliar opposite-sex conspecifics (one unrelated individual and one “estranged” sibling, from whom they had been separated for 27 days). Habituation tests with the odours of “estranged” siblings and courtship tests confirmed that the “estranged” siblings and their odours were treated as unfamiliar. Subjects spent significantly more time investigating unrelated individuals and their odours, than their “estranged” siblings and their odours, indicating discriminative behaviour toward less genetically similar individuals. The findings suggest that eusocial mole-rats can respond differentially to odours based on their degree of relatedness to the odour donors.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

9. influence of olfactory stimulus and sexual activity on gonadal steroids in eusocial mole-rats

Creator:
Hagemeyer, Petra, Lange, Simone, Broecker-Preuss, Martina, Burda, Hynek, Stopka, Pavel, and Dvořáková-Hortová, Kateřina
Type:
article and TEXT
Subject:
estrus, colpocytology, and Fukomys
Language:
English
Description:
The two studied sibling species of African mole-rats, Fukomys anselli and F. kafuensis, are blind, subterranean rodents that live in an eusocial families with only a single pair breeding whilst its offspring exhibit prolonged philopatry and do not breed. The reproductive skew is caused by incest avoidance through individual recognition of family members. The aim of the study is to contribute to basic understanding of priming capacities of olfactory stimuli and reproductive activity on biological state of a female. We compared hormonal profiles (normalized urinary estradiol- and progesterone concentration (mg/crea) and their temporal changes in females throughout three different test phases: I. Five week phase without manipulation; II. Five day phase with olfactory stimulation with odours of potential repreductive partners; III. Five day phase wih reproductive stimulation with respective partners. Colpocytology was performed to correlate spontaneous or induced estrus with vaginal cytological findings. There was a strong correlation between sexual activity of females (queens) on one side and high mean estradiol and progesterone levels on the other side as well as estradiol increase triggered by mating. No correlation was found between estrus phase and typical estrus like cells in colpocytological examinations.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/