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1.
布氏田鼠非取食性牧草消耗量的测定   总被引:5,自引:4,他引:1  
布氏田鼠 (Microtusbrandti)为内蒙古典型草原区的主要害鼠之一[1,6 ,8,9] 其危害主要表现为与牛羊争夺牧草资源。因此 ,测定其牧草消耗量 ,是定量地衡量其危害程度 ,推算鼠害防治经济阈值的重要基础。在牧草生长季节 ,该鼠对牧草的消耗主要分为两个方面 ,即取食量和非取食性消耗量 (布氏田鼠咬断而未取食的部分牧草或者食物残屑 )。有关该鼠食性与食量的研究已有一些报道[2 ,3 ,5] ,但对该鼠的非取食性牧草消耗量则缺乏研究。为此 ,本文开展了这项工作 ,为定量估算该鼠的危害程度提供依据。1 材料与方法本项研究是于 1997…  相似文献   

2.
布氏田鼠对主要贮草种类的选储嗜好   总被引:2,自引:0,他引:2  
布氏田鼠 (Microtusbrandti)为内蒙古典型草原区的主要害鼠 ,其危害主要表现在与牲畜争夺牧草资源[1,3 ,5,6,9] 。该鼠属不冬眠种类 ,冬季主要以洞群贮草仓库中的贮草为食 ,因此 ,研究其秋季集群的贮草习性 ,对于分析和了解该鼠的越冬生态特征具有一定的意义。有关布氏田鼠的贮草习性 ,已有一些报道[4 ,7] 。研究表明 ,在羊草 冷蒿 隐子草草场 ,布氏田鼠的越冬贮草以蒿属 (Artemisia)植物为主 ,其中冷蒿 (A .frigida)与黄蒿 (A .scoparia)占贮草比例超过 90 % [2 ] ,但上述研究均未涉及布氏田鼠…  相似文献   

3.
布氏田鼠 (Microtusbrandti)为内蒙古典型草原区的主要害鼠 ,其危害主要表现在与牛羊争夺牧草资源 ,破坏草场、引起草场沙化退化 ,以及传播疾病等三个方面[3,5,8] 。该鼠为不冬眠种类 ,冬季以储存于地下仓库中的牧草为食[9,10 ] 。因此 ,研究其秋季洞群的贮草面积与草场植被条件的关系 ,对于分析该鼠的越冬适应策略 ,并进一步提出草场鼠害的优化管理方案 ,具有重要意义。有关该鼠秋季贮草习性 ,已有一些文献报道[1,4 ,6 ,7] ,但涉及该鼠秋季洞群贮草面积与草场植被条件的关系的研究较少。为此 ,在内蒙古典型草原区开展了此项…  相似文献   

4.
在内蒙古典型草原区锡林郭勒盟研究了贮草期布氏田鼠(Lasiopodomys brandtii)采食距离及集群数量对采食量的影响。通过人为设置布氏田鼠洞群家族成员数量和采食距离,采用小麦(Triticum aestivum)为采食材料,测定了秋季自由生活状态下,采食距离为5~30 m范围内、每个洞群布氏田鼠数为3~11只范围内,布氏田鼠单次采食量的变化。结果表明,采食距离和家族成员数量对布氏田鼠单次采食量没有明显影响,采食距离和家族成员数量之间也不存在交互作用。布氏田鼠单次搬运麦粒数量平均为8.0粒/次,这可能与田鼠的搬运能力有关。  相似文献   

5.
布氏田鼠体重生长与栖息地植被条件的关系   总被引:3,自引:1,他引:2  
在内蒙古典型草原区多种不同植被条件栖息地中分析布氏田鼠当年雄鼠的体重生长差异。研究表明 ,布氏田鼠在不同植被条件下的体重生长具有显著的差异。在植被条件中等的草场 ,布氏田鼠的体重生长最佳 ,在植被条件优越的轻牧草场或者过度放牧草场 ,布氏田鼠体重生长一般 ,植被条件较差的重度放牧草场 ,布氏田鼠的平均体重较低。在不同类型草场 ,布氏田鼠可以通过调节体重大小和生长速度来适应各种不同类型的草场  相似文献   

6.
布氏田鼠(Microtus brandti)为内蒙古典型草原区的主要牧业害鼠,确定该鼠对草场植被的危害过程及相应危害量是寻求防治阈值的基础。1986年至1987年我们在内蒙古太仆寺旗建立野外围栏观测条件,并结合室内试验进行研究。现将结果简报于后。  相似文献   

7.
温湿度对小灵猫摄食活动及摄食量的影响   总被引:1,自引:0,他引:1  
钟福生  刘振湘 《兽类学报》2002,22(3):233-236
小灵猫 (Viverriculaindica)系食肉目、灵猫科、小灵猫属 ,为国家Ⅱ级重点保护物种 ,广布于我国淮河、长江流域及华南各省区[1,2 ] ,在湖南主要产于湘西、湘西南及湘南丘陵地带。关于环境因素对小灵猫的影响已有一些文献资料[3~ 5] ,但温、湿度与其摄食活动和摄食量之间的关系则尚未见报道。作者于 1 998年 1 2月至 2 0 0 0年 8月对小灵猫进行了驯养研究 ,就温度、湿度对小灵猫摄食活动、摄食量的影响进行了观察分析 ,现将结果报道如下 :1 材料与方法1 1 试验材料1 1 1 试验动物 实验用个体均于 1 998年 1 2月捕自…  相似文献   

8.
2005年5月,在内蒙古锡林郭勒盟阿巴嘎旗北部,研究了肝毛细线虫(Capillaria hepatica)对典型草原区雌性布氏田鼠(Lasiopodomys brandtii)繁殖参数的影响。采用标准夹线法捕获鼠类,对捕获的鼠类进行常规生物学解剖,根据虫卵有无确定肝毛细线虫病感染情况,记录鼠类名称、体长、体重、胴体重、繁殖特征以及肝毛细线虫病感染情况。由于体重是划分鼠类年龄的常用指标之一,结合布氏田鼠的繁殖特征研究数据,采用25.1~55.0 g之间的雌性个体作为本研究分析样本,并将其分为25.1~35.0 g、35.1~45.0 g和45.1~55.0 g体重(年龄)组。采用卡方检验比较分析同一体重(年龄)组内,肝毛细线虫病感染情况与雌性布氏田鼠妊娠率的关系,T检验分析感染情况与胎仔数的关系。结果显示,在各个体重(年龄)组中,感染肝毛细线虫组布氏田鼠雌鼠妊娠率均略低于未感染组,但感染情况与妊娠情况无显著相关关系(P0.05);感染肝毛细线虫布氏田鼠胎仔数低于未感染布氏田鼠,感染情况与胎仔数有显著相关关系(P0.05)。结果表明,肝毛细线虫病对布氏田鼠妊娠率无明显影响,但对布氏田鼠胎仔数有明显的负面影响。  相似文献   

9.
浑善达克沙地小毛足鼠的食量与食性动态   总被引:2,自引:0,他引:2  
采用夹捕取样法采集内蒙古浑善达克沙地各月份小毛足鼠的样本,根据对样本的颊囊与胃内容物的组成分析研究了浑善达克沙地小毛足鼠的食性及其季节动态。结果表明,该鼠主要取食植物种子,占其食物组成的85%以上,其余部分为昆虫与植物茎叶。通过对实验室内饲养的小毛足鼠日食量的测定表明,小毛足鼠的日食量(D)与体质量(M)关系可用数学表达式表示为D=1.422×lnM-1.780。结合其种群结构特征,可以计算出小毛足鼠日均消耗2g左右的植物种子。  相似文献   

10.
2005年5月和8月,在内蒙古锡林郭勒北部典型草原调查了肝毛细线虫对布氏田鼠种群的感染特征,分析肝毛细线虫对布氏田鼠的感染率与其性别、年龄、体重及种群密度的关系。结果表明:肝毛细线虫对布氏田鼠感染率没有性别差异,雄鼠与雌鼠的感染率相当;但是与布氏田鼠体重/年龄密切相关:幼鼠的感染率较低,成鼠感染率较高,感染率和平均感染度均随着个体年龄的增长而增高。布氏田鼠达到一定的年龄(或体重)后才可感染肝毛细线虫病,其最低感染体重为24.3 g。布氏田鼠的种群密度对肝毛细线虫的感染率和平均感染度没有明显的影响,但同一样地不同季节感染率不同,本次调查显示,2005年5月份感染率高于8月份群体感染率,同一样地的春季感染率与秋季感染率之间呈现出显著的正相关。  相似文献   

11.
Objective: High water consumption has been proposed as an aid to weight control and as a means of reducing the energy density of the diet. This study examines the relationship between water consumption and other drinking and eating patterns. Research Methods and Procedures: The National Health and Nutrition Examination Survey 1999 to 2001, with responses from 4755 individuals ≥18 years of age, provides the data for this cross‐sectional analysis. A cluster analysis was performed using z‐scores of specific food and beverage consumption to examine patterns. A multinomial logit analysis was used to examine sociodemographic characteristics of each dietary pattern and to examine the effects of water consumption on the likelihood of consuming a non–dairy caloric beverage. All results were weighted to be nationally representative and controlled for design effects. Results: Within the sample, 87% consumed water, with an average daily consumption of 51.9 oz (1.53 liters) per consumer. Water consumers drank fewer soft/fruit drinks and consumed 194 fewer calories per day. Water consumers (potentially a self‐selected sample) consumed more fruits, vegetables, and low‐ and medium‐fat dairy products. Four distinct unhealthy dietary patterns were found that included little or no water consumption. Older and more educated persons used healthier food patterns. Mexican dietary patterns were much healthier than dietary patterns of blacks. Discussion: Water consumption potentially is a dietary component to be promoted, but much more must be understood about its role in a healthy diet. Because high water consumption is linked with healthier eating patterns—patterns more likely to be followed by higher‐educated, older adults—the target of water promotion and healthy diet options should focus on younger and less educated adults.  相似文献   

12.
Assessments of urban metabolism (UM) are well situated to identify the scale, components, and direction of urban and energy flows in cities and have been instrumental in benchmarking and monitoring the key levers of urban environmental pressure, such as transport, space conditioning, and electricity. Hitherto, urban food consumption has garnered scant attention both in UM accounting (typically lumped with “biomass”) and on the urban policy agenda, despite its relevance to local and global environmental pressures. With future growth expected in urban population and wealth, an accounting of the environmental footprint from urban food demand (“foodprint”) is necessary. This article reviews 43 UM assessments including 100 cities, and a total of 132 foodprints in terms of mass, carbon footprint, and ecological footprint and situates it relative to other significant environmental drivers (transport, energy, and so on) The foodprint was typically the third largest source of mass flows (average is 0.8 tonnes per capita per annum) and carbon footprint (average is 2.1 tonnes carbon dioxide equivalents per capita per annum) in the reviewed cities, whereas it was generally the largest driver of urban ecological footprints (average is 1.2 global hectares per capita per annum), with large deviations based on wealth, culture, and urban form. Meat and dairy are the primary drivers of both global warming and ecological footprint impacts, with little relationship between their consumption and city wealth. The foodprint is primarily linear in form, producing significant organic exhaust from the urban system that has a strong, positive correlation to wealth. Though much of the foodprint is embodied within imported foodstuffs, cities can still implement design and policy interventions, such as improved nutrient recycling and food waste avoidance, to redress the foodprint.  相似文献   

13.
Analysis of food consumption and agricultural production trends in Sweden has focused on domestic food production levels and yields, overlooking human dependence on ecosystem support. We estimate the ecosystem areas appropriated (ArEAs) for agricultural production (crop and animal feed production and grazing in arable land and marine production for fishmeal used in animal feed) to satisfy Swedish food consumption needs from 1962 to 1994. The total agroecosystem areas worldwide supporting Swedish food consumption (that is, domestic production less exports plus imports) have declined by almost one-third since the 1960s as a result of consumption changes and agricultural intensification. By 1994, Swedish consumption of domestic food crops was halved and consumers relied on agricultural areas outside Sweden to satisfy more than a third (35%) of food consumption needs. Surprisingly, 74% of manufactured animal feed ArEAs were from imported inputs. Moreover, marine ArEAs equal to 12% of the total appropriated areas were needed to support fishmeal usage in animal feed. The results show that domestic agricultural areas do not support Swedish food consumption and that the bulk of manufactured feed used in animal products’ production in Sweden is supplied by ecosystems of other nations. These are hidden subsidies of nature, not explicit in Swedish national agricultural policy. Sweden must recognize its high level of dependence on the capacity of ecosystems of other nations to supply its food needs. Ignorance of ecosystem support may increase vulnerability.  相似文献   

14.

Background

Gestational diabetes prevalence is increasing, mostly because obesity among women of reproductive age is continuously escalating. We aimed to investigate the incidence of gestational diabetes according to the consumption of fast food in a cohort of university graduates.

Methods

The prospective dynamic “Seguimiento Universidad de Navarra” (SUN) cohort included data of 3,048 women initially free of diabetes or previous gestational diabetes who reported at least one pregnancy between December 1999 and March 2011. Fast food consumption was assessed through a validated 136-item semi-quantitative food frequency questionnaire. Fast food was defined as the consumption of hamburgers, sausages, and pizza. Three categories of fast food were established: low (0–3 servings/month), intermediate (>3 servings/month and ≤2 servings/week) and high (>2 servings/week). Non-conditional logistic regression models were used to adjust for potential confounders.

Results

We identified 159 incident cases of gestational diabetes during follow-up. After adjusting for age, baseline body mass index, total energy intake, smoking, physical activity, family history of diabetes, cardiovascular disease/hypertension at baseline, parity, adherence to Mediterranean dietary pattern, alcohol intake, fiber intake, and sugar-sweetened soft drinks consumption, fast food consumption was significantly associated with a higher risk of incident gestational diabetes, with multivariate adjusted OR of 1.31 (95% conficence interval [CI]:0.81–2.13) and 1.86 (95% CI: 1.13–3.06) for the intermediate and high categories, respectively, versus the lowest category of baseline fast food consumption (p for linear trend: 0.007).

Conclusion

Our results suggest that pre-pregnancy higher consumption of fast food is an independent risk factor for gestational diabetes.  相似文献   

15.
红褐斑腿蝗的食物消耗与利用及其对温度的依赖性   总被引:3,自引:0,他引:3  
昆虫是变温动物 ,外界温度的波动会影响昆虫的体温 ,这也必然会影响昆虫的新陈代谢 ,从而引起一系列生理生化反应。红褐斑腿蝗 [Catantopspin guis(Stal) ]是浙江农田常见的蝗类害虫 ,分布广 ,数量多 ,常为害玉米 (Zeamays)、豆类 (Glycinemax)及茶树 (Camlliasinensis)。据作者观察 ,该种蝗虫常以成虫越冬 ,而浙江省冬季最冷的 1月份平均气温为 2 5~ 7 5℃ ,极端低温多年平均在 - 8℃以下。文献研究表明 ,红褐斑腿蝗的过冷却点可达 - 2 0℃以下 (有关结果拟另文发表 ) ,显示其具…  相似文献   

16.
光照强度对中华鳖稚鳖摄食和生长的影响   总被引:26,自引:8,他引:26  
在3000,1000,300和101x的光照强度下,测定了中华鳖稚鳖的最大日摄食量和特定生长率。结果表明,光照强度对中华鳖稚瞥珠最大日摄食量影响显著,随着光照强度的减弱,中华鳖稚鳖的最大日摄食量逐渐增加,二者之间呈线性负相关。  相似文献   

17.

Objective

To examine whether psychosocial factors mediate (explain) the association between socioeconomic position and takeaway food consumption.

Design

A cross-sectional postal survey conducted in 2009.

Setting

Participants reported their usual consumption of 22 takeaway food items, and these were grouped into a “healthy” and “less healthy” index based on each items'' nutritional properties. Principal Components Analysis was used to derive three psychosocial scales that measured beliefs about the relationship between diet and health (α = 0.73), and perceptions about the value (α = 0.79) and pleasure (α = 0.61) of takeaway food. A nutrition knowledge index was also used. Socioeconomic position was measured by highest attained education level.

Subjects

Randomly selected adults (n = 1,500) aged between 25–64 years in Brisbane, Australia (response rate  =  63.7%, N = 903).

Results

Compared with those with a bachelor degree or higher, participants with a diploma level of education were more likely to consume “healthy” takeaway food (p = 0.023) whereas the least educated (high school only) were more likely to consume “less healthy” choices (p = 0.002). The least educated were less likely to believe in a relationship between diet and health (p<0.001), and more likely to have lower nutritional knowledge compared with their highly educated counterparts (p<0.001). Education differences in beliefs about the relationship between diet and health partly and significantly mediated the association between education and “healthy” takeaway food consumption. Diet- and health-related beliefs and nutritional knowledge partly and significantly mediated the education differences in “less healthy” takeaway food consumption.

Conclusions

Interventions that target beliefs about the relationship between diet and health, and nutritional knowledge may reduce socioeconomic differences in takeaway food consumption, particularly for “less healthy” options.  相似文献   

18.
The temperature and mass dependence of maximum consumption rate was measured for larval and early juvenile spotted seatrout Cynoscion nebulosus . Maximum consumption ( C MAX) estimates were obtained from feeding and gut evacuation experiments on larvae (3·8–19 mm standard length, L S) at three temperatures (24, 28 and 32° C), and maximum consumption experiments on juveniles at three temperatures (20, 26 and 32° C). Feeding levels were determined for larvae fed live prey ( Brachionus plicatilis and Artemia salina ) ad libitum . The midgut and total evacuation times were estimated for fish feeding continuously and discontinuously using alternate meals of tagged and untagged live prey. Temperature and fish size had significant effects on gut evacuation and consumption. The gut evacuation time increased with increasing fish size, and decreased with increasing temperatures. Mass‐specific midgut contents increased for small larvae <0·156 mg dry mass ( M D)( c . 4 mm L S), and decreased for larger larvae and juveniles. Maximum consumption was modelled by fitting a polynomial function to a reduced dataset of individuals feeding at high levels. The C MAX model predicted an initial increase in specific feeding rate from 70 to 155% M D day−1 for small larvae, before declining for larger larvae and juveniles.  相似文献   

19.
This is a review of the data available on the population subdivision and life cycle of the Minke whale, the most abundant whalebone whale in the World Ocean. Different methods of estimation and calculation of the rate of food consumption by this species, the latter including those developed for the Sea of Okhotsk, are compared.  相似文献   

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