不同季节蛋鸡饲料养分浓度的研究Ⅱ.高温期罗曼蛋鸡日粮的优化研究

在高温夏季（１９９３年７月１日～９月３０日，合肥地区，开放式鸡舍，舍温２７．９～３８．７℃，平均３２．３℃），用６种不同配方的日粮饲喂处于相同生境的６组２３～３６周龄罗曼蛋鸡。按罗曼公司推荐的饲养标准配制第１组日粮；对第２～６组日粮养分浓度作适当调整。饲养结果表明：各组间罗曼蛋鸡产蛋率、饲料转化率和产蛋饲料成本有显著（Ｐ＜０．０５）或极显著（Ｐ＜０．０１）差异。其中，第５组鸡产蛋率（８３．９３％）和饲料转化率（４３．６４％）均为最高（Ｐ＜０．０１），比第１组鸡产蛋率（７８．９１％）和饲料转化率（４１．２６％）分别提高６．３６％（Ｐ＜０．０５）和５．７７％（Ｐ＜０．０５）；第５组鸡产蛋饲料成本（２．５５元／ｋｇ）比第１组鸡产蛋饲料成本（２．９２元／ｋｇ）降低１４．５１％（Ｐ＜０．０１）。第５组日粮配方（％）为：玉米６１．０、小麦麸３．０、大豆粕１７．０、鱼粉４．０、菜籽饼４．３、蛋氨酸０．１４、赖氨酸０．０５、骨粉０．８、石粉８．５、磷酸氢钙０．８、食盐０．３１、禽用微量元素添加剂０．１２、罗曼多维素０．０１８。     

Comparative water snake ecology: conservation of mobile animals that use temporally dynamic resources

Obtaining information on movement and spatial patterns of animals and understanding the factors that shape their movements about the landscape are critical steps in designing conservation strategies. We conducted a comparative radiotelemetry study of two snake species, the northern water snake, Nerodia sipedon sipedon, and the imperiled copperbelly water snake, Nerodia erythrogaster neglecta, in northwest Ohio and southern Michigan to assess differences in movement patterns, spatial ecology, and resource use. N. e. neglecta moved distances (53.3 ± 7.1 m/day and 4809 ± 603 m/year) over twice as far as N. s. sipedon (25.6 ± 2.7 m/day and 2244 ± 228 m/year), and used areas nearly four times larger (15.8 ± 2.7 ha) than N. s. sipedon (4.0 ± 0.9 ha). When wetlands were widely dispersed in the landscape, N. e. neglecta moved longer distances and used larger areas, whereas spatial and movement patterns in N. s. sipedon were unaffected by wetland spatial distribution. N. e. neglecta’s long movements and large area use are likely related to its use of variable resources such as ephemeral wetlands and anuran prey. N. s. sipedon used more permanent wetlands and preyed more generally on fish and anurans. Habitat alterations that change the spatial distribution of wetlands in the landscape, such as the loss of small isolated wetlands, have likely increased energetic costs and mortality rates for N. e. neglecta. Conservation strategies for vagile wetland animals that use spatially and temporally variable resources over broad spatial scales should focus on protecting and restoring large areas with numerous, heterogeneous wetlands.     

甘南草原3种啮齿动物的食性及其营养生态位特征

研究啮齿动物的食性及其营养生态位特征不仅可以了解高寒草甸环境变化下物种的食性适应特征,还可探讨多种啮齿动物的种间关系。本研究采用粪便显微组织观察法,分析了甘南草原高原鼠兔（Ochotona curzoniae）、高原鼢鼠（Eospalax baileyi）和喜马拉雅旱獭（Marmota himalayana）3种啮齿动物的食性及营养生态位特征。结果发现：3种啮齿动物所采食的植物种类基本相同,但其比例各异;高原鼢鼠所采食的植物主要是珠芽蓼（Polygonum viviparum）和鹅绒委陵菜（Potentilla anserina）等杂类草,且对莎草科（Cyperaceae）植物的采食量显著高于其它两种动物,高原鼠兔主要采食禾本科（Poaceae）植物,喜马拉雅旱獭则主要采食禾本科和菊科（Asteraceae）植物;营养生态位宽度依次为喜马拉雅旱獭>高原鼢鼠>高原鼠兔,其中高原鼠兔与喜马拉雅旱獭的营养生态位重叠最大（0.52）。3种啮齿动物在食物上存在分化,营养生态位分离,是其共存的重要原因。     

果子狸对玉米、豆粕和鱼粉型日粮的消化率测定

本试验测定了 4只果子狸对玉米、豆粕和鱼粉型日粮的消化率。结果表明 :果子狸对该日粮的营养成分的消化率分别为 :粗蛋白 (CP) 68 31 % ,干物质 (DM ) 5 3 0 5 % ,精脂肪 (CL)5 8 30 % ,能量 (GE) 61 31 %。