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Start Over Creator Sedláček, František Creator Zima, Jan

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/

9. Integumentary odoriferous glands in Meriones libycus

Creator:
Djeridane, Yasmina, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
integumentary odoriferous gland, gerbil, histology, and scent-related behavior
Language:
English
Description:
Macroscopic and histological examinations of the integument demonstrate that Meriones libycus possesses a varied assortment of skin scent-glands: alveolar sebaceous holocrine mouth corner gland; branched tubulo-acinar sero-mucous merocrine gular gland; sudoriferous merocrine palmar and plantar glands; alveolar sebaceous holocrine abdominal gland and alveolar sebaceous holocrine preputial and clitorial glands. Related behavior observations on captive animals in laboratory conditions, demonstrate that this species has several patterns of scent emission and marking: the mouth-corner glands, pressed and rubbed by the forepaws, are apparently involved in individual recognition via naso-oral contacts. Runways and movements are perhaps scent-marked environment with plantar and palmar secretions. The transfer of scent from the site of production to the substrate, may help in the animal's orientation. M. libycus marks low-lying objects in its environment by rubbing them with the abdominal pad, whereas, when objects are higher, the animal marks them with the gular area. The deposit of olfactory marks are frequently investigated by conspecifics. It appears that abdominal scent marking is closely associated with social status, agonistic relationships and territoriality. the latter notion is also associated with gular scent marking. The abdominal marking behavior as well as the size of the scent abdominal gland are sexually dimorphic in favor of the male. Chemical signals of preputial and clitorial glands may convey information such as sex and reproductive status. Male castration induces an extreme atrophy of the preputial and abdominal sebaceous glandular tissues, whereas this operation has no effect on the morphology of oral, gular, palmar and plantar glandular tissues. The preputial and abdominal gland changes induced by castration, are prevented by testosterone administration. these suggest that the preputial and abdominal gland integrities are androgen-dependent in the male.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

10. Metabolic rate, thermoregulation and distribution of greater long-tailed hamster (Cricetulus triton) in China

Creator:
Wang, De-Hua, Wang, Zu-Wang, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
greater long-tailed hamster, Cricetulus triton, basal metabolic rate, BMR, thermoregulation, ecophysiology, and distribution
Language:
English
Description:
Metabolic rate, body temperature, and thermal conductance were determined in the greater long-tailed hamster (Cricetulus triton) at a temperature range of 5-36 °C. Oxygen consumption was measured by using a closed circuit respirometer. The thermal neutral zone was 39-34 °C. Within a temperature range of 5-31 °C hamsters could maintain a stable body temperature at a mean of 36.7±0.1 °C. Mean basal metabolic rate within thermal neutrality was 1.23±0.02 ml O2/g.h. Total thermal conductance was maintained within a temperature range of 5-15 °C (mean = 0.12±0.00 ml O2/g.h °C). The ecophysiological properties of the greater long-tailed hamster were: (1) a higher metabolic rate than predicted by the allometric scaling equation for eutherian mammals, but lower than that predicted for all rodents and slightly higher than predicted for cricetid rodents; (2) the body temperature was relatively low; (3) thermal conductance was relatively higher than predicted on the basis of body weight. All these characteristics are closely related to the species' life style (i.e. a burrowing, solitary, nocturnal species that feeds mainly on crop seeds and a small fraction of young crop shoots and insects). Greater long-tailed hamsters are primarily distributed in the northern Yangtse River area of China and cannot survive in extremely dr and alpine areas. We propose that the ecophysiological characteristics of the species might constrain its distribution and range extension into extreme deserts, high altitudes and cold areas.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/