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Births are highly synchronized among females in many mammal populations in temperate areas. Although laying date for a given female is also repeatable within populations of birds, limited evidence suggests low repeatability of parturition date for individual females in mammals, and between-population variability in repeatability has never, to our knowledge, been assessed. We quantified the repeatability of parturition date for individual females in five populations of roe deer, which we found to vary between 0.54 and 0.93. Each year, some females gave birth consistently earlier in the year, whereas others gave birth consistently later. In addition, all females followed the same lifetime trajectory for parturition date, giving birth progressively earlier as they aged. Giving birth early should allow mothers to increase offspring survival, although few females managed to do so. The marked repeatability of parturition date in roe deer females is the highest ever reported for a mammal, suggesting low phenotypic plasticity in this trait.  相似文献   
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The European roe deer (Capreolus capreolus) is an interesting model for molecular ecology studies because of its abundance and adaptability across a range of environments (including human‐modified habitats), and because of its increasing impacts on agricultural crops and on regenerating forests. We identify polymorphic microsatellites in two managed populations of roe deer in France by using cross‐species amplification of primers from other Cervids and from Bovids. Of the 62 primer pairs tested, 45 amplified microsatellites in roe deer, and 34 were polymorphic. Eleven primer pairs were selected for multiplex gel‐loading for routine genotyping of the studied populations.  相似文献   
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Abstract The Eurasian lynx (Lynx lynx) causes large loss of free-ranging domestic sheep in Norway. We tested whether the observed higher kill rates by male lynx than female lynx were related to an association between the availability of the main natural prey, as measured by roe deer (Capreolus capreolus) habitat suitability, presence of sheep, and habitat selection of male and female lynx. We found that lynx selected areas with high roe deer suitability during summer and winter. Moreover, during summer, compared to male lynx, females had greater selection for roe deer areas and a stronger avoidance for sheep grazing areas, which suggests that previously observed differences in kill rates between male and female lynx can be attributed to sex-specific habitat use during summer. The connection between lynx habitat use and roe deer also was reflected in a positive relationship between the roe deer suitability of a sheep grazing area and the total loss of lambs, which suggests that livestock, rather than being actively selected, are mainly killed by lynx incidentally when encountered during other lynx activities (e.g., searching for natural prey species). Therefore, any management practice that separates lynx and sheep, such as concentrating livestock into small patches or less preferred habitats, may reduce depredation.  相似文献   
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雪尿分析技术是北方冬季有蹄类种群营养状况评价的可靠性指数。本文通过对兴隆镇小东林场和三江自然保护区1999 及2000 年冬季狍50 个雪尿、尿液样本采集及分析, 用以评价在不同类型的栖息地中狍冬季的营养状况, 结果表明: 雪尿分析可以评价狍冬季的营养状况及其变化; 雪尿中较低的尿素氮与肌酸酐的比率表明两地区狍基本上处于营养不良早期阶段, 反映了食物资源可利用性低、食物营养质量低造成外源蛋白质和能量摄入不足, 而使狍大量消耗体脂肪, 并通过对尿液化学成分的重吸收利用而保持其在尿液中排出量最低, 使机体内源蛋白质分解代谢处于较低状态; 三江1999 年冬季狍营养状况相对较差, 而2000 年情况较好; 幼体及亚成体处于营养不良中期阶段。
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We investigated the activity patterns of a European roe deer (Capreolus capreolus) population living in a forested Apennine area in central Italy, in order to shed light on the environmental and biological factors that were expected to account for the observed activity patterns on daily and yearly bases. Daily and seasonal activity patterns of 31 radio-collared roe deer were assessed through sessions of radio tracking for a total period of 18 consecutive months. Roe deer showed bimodal activity patterns throughout the year, with the two highest peaks of activity recorded at dawn and dusk. Activity patterns of males and females differed during the territorial period (from early spring to late summer), whereas they did not during the nonterritorial period. Most likely, behavioral thermoregulation can be held responsible for variation of daily activity patterns in different seasons. In winter, for instance, activity during the dawn period was significantly higher than in other seasons and daylight activity was significantly higher than at night. Nocturnal activity was highest in summer and lowest in winter. During the hunting season, moreover, roe deer showed lower activity levels than during the rest of the year. The prediction that roe deer would show lower activity levels during full moon nights, when the predation risk was assumed to be higher, was not confirmed by our data. Activity rhythms in roe deer were thus subjected to both endogenous and environmental factors, the latter working as exogenous synchronization cues. Accordingly, in changing environmental and ecological conditions, a circadian cycle of activity could be seen as the result of complex interactions among daily behavioral rhythm, digestive physiology, and external modifying factors.  相似文献   
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