Meadow voles,Microtus pennsylvanicus,can discriminate between scents of individual house cats,Felis catus

Individual discrimination provides animals the opportunity to adjust their exposure and behavior when interacting with other animals, both conspecifics and heterospecifics. Meadow voles, Microtus pennsylvanicus, were exposed to scents of house cats, Felis catus. Our first experiment tested whether meadow voles could discriminate between caudal, interdigital, and facial scents produced by a cat with a habituation–dishabituation paradigm. Upon exposure to the familiar scent and a novel one, meadow voles did not investigate either scent more than the other. Our second experiment tested whether meadow voles discriminate between the facial scents of different cats. When exposed to a familiar scent of one cat and the unfamiliar scent of another cat, the meadow voles did discriminate and investigated the unfamiliar scent more than the familiar scent. The results suggest that meadow voles will discriminate between cats using any scent that the cat may inadvertently leave within the environment, thereby reducing the vole's risk of predation by that individual.     

Role of small mammals in the persistence of Louping-ill virus: field survey and tick co-feeding studies

Louping-ill (LI) is a tick-borne viral disease of red grouse, Lagopus lagopus scoticus Lath. (Tetraonidae: Galliformes), and sheep, Ovis aries L. (Bovidae: Artiodactyla), that causes economic loss to upland farms and sporting estates. Unvaccinated sheep, grouse and mountain hares, Lepus timidus L. (Leporidae: Lagomorpha), are known to transmit LI virus, whereas red deer, Cenrus elaphus L. (Cervidae: Artiodactyla), and rabbits, Oryctolagus cuniculus L. (Leporidae: Lagomorpha), do not. However, the role of small mammals is unknown. Here, we determine the role of small mammals, in particular field voles, Microtus agrestis L. (Muridae: Rodentia), in the persistence of LI virus on upland farms and sporting estates in Scotland, using field sampling and non-viraemic transmission trials. Small mammals were not abundant on the upland sites studied, few ticks were found per animal and none of the caught animals tested seropositive to LI virus. Laboratory trials provided no evidence that small mammals (field voles, bank voles, Clethrionomys glareolus L. (Muridae: Rodentia), and wood mice, Apodemus sylvaticus L. (Muridae: Rodentia), can transmit LI virus between cofeeding ticks and, in the field, LI virus was prevalent only in areas with known LI virus competent hosts (grouse, mountain hares or unvaccinated sheep) and absent elsewhere. In contrast to the case of tick-borne encephalitis (TBE) virus in Europe, it is concluded that small mammals seem to be relatively unimportant in LI virus persistence.     

胎仔数与父本缺失对棕色田鼠幼仔体重发育的影响

室内饲养条件下,测量了出生后不同发育阶段棕色田鼠Microtus mandarinus的体重,并探讨了胎仔数(分别为1只、2只、3只和4只)及父本缺失(母鼠单独抚育)对幼仔体重发育的影响.结果表明,棕色田鼠出生后第一周体重的瞬时生长率最高,此后逐步下降;出生后28～35 d,体重增益最大(P<0.05).出生后7 d,不同胎仔数的体重没有明显差异,但至断乳时(出生后21 d),胎仔数为2只的幼仔平均体重明显高于其它胎仔数的平均体重(P<0.05).与双亲抚育相比,母鼠单独抚育的幼仔在断乳时的体重明显下降(P<0.05).这些结果说明,哺乳期内棕色田鼠幼仔的体重发育与胎仔数有关.由于棕色田鼠是单配制,双亲育幼,父本雄鼠的缺失减少了亲本投资,影响了幼仔的身体发育.     

Regeneration of Salix arbuscula and Salix lapponum within a Large Mammal Exclosure: The Impacts of Microsite and Herbivory

Over‐grazing or browsing by large herbivores may result in the loss of individual plant species or entire plant communities. Restoration schemes often involve exclusion of large mammals, but the resulting changes in vegetation may alter other important ecological processes such as regeneration, via changes in microsite availability for seed germination or increases in populations of seedling predators. Working within a large fenced area from which large mammals were excluded, we experimentally tested the effects of microsite, small herbivores, and their interactions on post‐dispersal seed and early seedling mortality of one nationally scarce (Salix arbuscula) and one nationally rare (S. lapponum) species of montane willow. Seeds were sown in three different microsites: natural vegetation, mown vegetation (mimicking grazed sward), and bare ground. Small exclosures and slug pellets were used to examine the effects of small mammal and slug predation, respectively. Survival of seedlings was monitored during the summer following planting. The presence of bare ground, rather than the absence of herbivores, was of over‐riding importance for early seedling survival and establishment. Protecting seedlings from small mammals made no difference to the levels of survival; however, protecting seedlings from slugs (Arion spp.) resulted in approximately 45% of seedlings surviving until the end of the summer compared to only 30% when seedlings were available to slugs. Although excluding large herbivores may increase seed production of existing individuals, the impacts of changes to plant communities on processes such as regeneration need to be considered if restoration projects are to be fully successful.     

The integrated processing response of voles to fibre content of natural diets

1. Two species of voles were fed high fibre (barnyard grass) and low fibre (alfalfa) diets to test the integrated processing response (IPR) hypothesis. This hypothesis states that many herbivores are able to maintain their required intake of digestible nutrients and energy on diets with very different fibre content because of compensatory changes in intake of food, size of gastro-intestinal (GI) tract, passage rates of fibre and absorptive capacity of the GI tract.
2. As predicted by the IPR hypothesis, each species of vole maintained a similar intake of digestible dry matter on the two different diets. Both species also had greater intake, larger GI size, shorter mean retention times and greater GI mass (an indicator of epithelial mass and absorptive capacity) when fed grass than when fed alfalfa.
3. The two species differed in that meadow voles, the more active species, had greater total intake and obtained a greater amount of digestible dry matter from either diet than did prairie voles. Meadow voles also consume more grass in the field than do prairie voles, and they digested grass better than did prairie voles. Prairie voles, which consume more dicots in the field, digested alfalfa better than did meadow voles.
4. Meadow voles had longer GI tracts, particularly small intestines, than did prairie voles, which may be linked to their greater ability to digest grass. However, meadow voles did not have larger caeca than prairie voles, even though caecal size increased on grass diets for both species. The GI size of prairie voles fed grass increased more than did the GI size of meadow voles, and this may have enabled prairie voles to utilize a grass diet, though they prefer to eat dicots. Greater selection of leaves, which have less fibre than stems, and longer mean retention times of food may account for better digestion of alfalfa by prairie voles.     

Phylogenetic analysis of Alpine voles of the Microtus multiplex complex using the mitochondrial control region

To elucidate the phylogenetic relationships of Alpine voles comprising the Microtus multiplex complex and related species the mitochondrial control region ( CR ) was employed as a genetic marker. Forty specimens were analysed representing the taxa Microtus liechtensteini , Microtus multiplex , and Microtus bavaricus (samples from 11 geographic regions) as well as specimens of Microtus subterraneus , Microtus tatricus , Microtus arvalis , Microtus agrestis , Microtus oeconomus , and Chionomys nivalis. The haplotypes from Tuscany and the Swiss canton of Valais can be ascribed to M. multiplex , whereas the haplotypes isolated from the geographic samples from Croatia, Slovenia, Carinthia, Styria, East Tyrol, and South Tyrol represent M. liechtensteini . The molecular data indicate that the distribution range of M. liechtensteini extends further to the north (Upper Styria) than has been assumed earlier. The haplotypes of M. bavaricus , together with the populations from North Tyrol, form a cluster clearly separated from M. liechtensteini . This result suggests that the North Tyrolean samples belong to M. bavaricus , a species thought to be extinct. Microtus tatricus splits off at the basis of the multiplex complex. Our sequence data do not support a close relationship between M. bavaricus and M. tatricus . The phylogenetic relationships deduced from the sequence data favour a hypothesis assuming three glacial refugia, in which M. multiplex , M. liechtensteini and M. bavaricus , respectively, survived the last one or two Alpine glaciations.     

棕色田鼠探究行为对同种个体气味源反应格局的分析

通过观察非动情期的棕色田鼠对麻醉的同种个体身体气味源的探究行为 ,包括雄鼠对麻醉雄鼠和雌鼠的嗅闻、雌鼠对麻醉雄鼠和雌鼠的嗅闻 ,分析了棕色田鼠在社会探究中对不同气味源的反应格局。结果表明 ,棕色田鼠对同种个体肛殖区和面部的嗅闻频次及嗅闻持续时间最多 (P <0 0 5 ) ;对背部、腹部、肋部嗅闻的频次和持续时间较少。在对同一部位的嗅闻中 ,在嗅闻频次上 ,雄鼠对雄鼠的嗅闻、雌鼠对雌鼠的嗅闻以及雌鼠对雄鼠的嗅闻都显著多于雄鼠对雌鼠的嗅闻 (P <0 0 5 ) ;在嗅闻时间上 ,性别组合对同一部位的探究行为没有显著影响 ,但气味源与性别组合有交互作用 (P <0 0 5 ) ,影响探究行为。这些结果说明棕色田鼠的肛殖区和面部是重要的气味源 ,而且在对同一气味源的探究中存在性别差异。但在非动情期 ,异性间的探究并不总是高于同性间的探究     

Familiarity and partner preferences in female common voles, <Emphasis Type="Italic">Microtus arvalis</Emphasis>

Captive female common voles (Microtus arvalis) had a clear social preference for familiar males in a standard preference test. Cohabitation for a short period resulted in preferences for familiar partners, and females spent eight times more time in body contact with a familiar male than with an unfamiliar male. Females also displayed stranger-directed aggression. Our results suggest that the common vole is a species with selective partner preferences and a tendency to form tight social relationships and stable male–female associations.     

雌性布氏田鼠对不同共居时间雄性气味的识别与记忆

啮齿动物的社会识别包括对化学信号的辨别、学习和记忆。田鼠属动物雌雄成年个体共居一定时间后,可以利用气味信号来识别配偶。本研究将成年雌雄布氏田鼠配对饲养12 h、18 h、24 h,确认发生交配行为形成配对关系后,分开单独饲养6 h,取配偶雄鼠和陌生雄鼠巢垫物作为个体气味,在气味选择箱中观察雌鼠对配偶雄鼠和陌生雄鼠气味信号的探究和选择行为,从而探讨不同共居时间雌性布氏田鼠对配偶气味信号的识别与记忆的影响。研究结果表明:共居时间影响雌性布氏田鼠对配偶气味的识别与记忆;共居时间越长,雌鼠在气味探究和选择时间上对配偶气味偏好越明显;共居24 h 后,雌性布氏田鼠能够识别出配偶雄鼠的气味信号并形成记忆,这样的记忆维持时间至少是6 h。     

Effects of fasting and refeeding on body mass,thermogenesis and serum leptin in Brandt's voles (Lasiopodomys brandtii)

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To investigate the effect of fasting and refeeding on the body mass, thermogenesis and serum leptin in Brandt's voles, the changes in body and body fat mass, resting metabolic rate (RMR), mitochondrial cytochrome c oxidase (COX) activity in liver and brown adipose tissue (BAT), uncoupling protein 1 (UCP1) content of BAT, serum leptin level and post-fasting food intake were monitored and measured.