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排序方式: 共有1086条查询结果,搜索用时 12 毫秒
991.
对日月山养鹿场围栏放牧的10头梅花鹿公鹿的7项血清生理指标进行了测定,并与祁连白唇鹿、祁连马鹿、祁连梅花鹿的某些生理指标进行比较。结果表明,日月山梅花鹿血清总蛋白显著低于祁连白唇鹿、祁连马鹿及祁连梅花鹿(P<0.01);日月山梅花鹿血清无机磷显著低于祁连白唇鹿(P<0.01),其他血清生理指标无显著差异(P>0.05)。 相似文献
992.
There is a growing interest on the potential interplay between weather, habitat, and interspecific competition on population dynamics of wild herbivores. Favorable environmental conditions may buffer the negative effects of competition; conversely, competition may be expected to be stronger under harsh environmental conditions. We investigated relationships between competitor abundance, weather, and habitat cover on density and local distribution of a medium-sized herbivore, the roe deer Capreolus capreolus, as well as its spatial overlap with fallow deer Dama dama in a Mediterranean protected area. Over 11 years (2007–2017), roe deer density was not affected by spring–summer rainfall in the previous year and decreased with increasing density of fallow deer in the previous year. Hence, over the considered temporal scale, results supported a major role of competition over weather in influencing population trends of roe deer. At a finer spatial scale, roe deer occupancy was negatively affected by local abundance of fallow deer, especially in “poorer” habitats. We found a slight support for a positive effect of fallow deer density on interspecific spatial overlap. Moreover, fine-scale spatial overlap between deer species increased with decreasing rainfall in spring–summer. Fallow deer were introduced to our study area in historical times and their role as superior competitors over roe deer has been found also in other study areas. We suggest a potential role of harsh weather conditions during the growing season of vegetation (i.e. scarce rainfall) in triggering the potential for ecological overlap, emphasizing the negative effects of interspecific competition. 相似文献
993.
先后分3批次,对176头梅花鹿进行了增茸试验。结果,添喂纤维素酶曲组比对照组,鹿茸产量分别提高17.38%、26.78%和31.81%,平均每头增产129g。试验组采食量比对照组低7.48%,饲料消化率随纤维素酶曲添加水平的提高而提高。粗蛋白、酸性洗涤纤维(ADF)和中性洗涤纤维(NDF)的消化率在添喂纤维素酶曲70g/头组,分别提高9.48%(P<0.01.)、7.82%(P<0.05)和8.81%(P<0.01).试验组鹿茸氨基酸和无机元素含量都有增加的趋势。血清氨基酸除胱氨酸和组氨酸外,其它氨基酸试验组均有不同程度的提高,无机元素含量除锰外,其它元素试验组均高于对照组。 相似文献
994.
梅花鹿胎盘脂质的抗衰老作用 总被引:10,自引:0,他引:10
观察了梅花鹿胎盘脂质(0.25 g/kg)对青年小鼠(1 月龄)和老年小鼠(24 月龄)某些衰老生化指标的影响。结果表明,鹿胎盘脂质可显著抑制小鼠脑和肝脏中单氨氧化酶-B(MAO-B)的活性,提高脑和肝脏中超氧化物歧化酶(SOD)的活性;降低小鼠心肌组织脂褐素的含量;明显提高小鼠皮肤和尾腱中羟脯氨酸(HYP)的含量。鹿胎盘脂质对老年小鼠上述生化指标的影响较青年小鼠更明显,提示鹿胎盘脂质对老年小鼠具有抗衰老作用。 相似文献
995.
西丰梅花鹿种公鹿茸重性状表型参数的统计分析 总被引:2,自引:2,他引:2
对西丰梅花鹿种公鹿茸重性状表型参数的统计分析 ,结果表明 ,生茸佳期为 3~ 8锯 ,生茸最佳年龄为 6锯 ,达 (5 0 2± 1 46)kg ,6锯的产茸量极显著高于 1~ 5锯的产茸量(P <0 0 1 ) ;1~ 6锯的种公鹿鲜茸重与年龄呈强正相关 (r =0 833,P <0 0 1 ) ,其线性回归方程为 y=1 350 +0 679x ;各锯别与产茸量间相关系数统计及显著性检验结果为 :1与 2锯 ,2与 3,4,5,6锯 ,3与 4,5,6锯 ,4与 6,7锯间呈极显著正相关 (P <0 0 1 ) ,其余各锯相关不显著(P >0 0 5)。此统计结果为早期选种、制定生产计划和任务、产茸量标准及是否符合种用性能提供了科学依据。 相似文献
996.
The intensity of deer herbivory, rather than simply the deer population density, directly affects the forest ecosystem, but a linear relationship between these two factors has generally been assumed. To assess their relationship, we investigated deer population density and tree sapling vegetation in six forests with different deer density on Yakushima Island, Japan. The feeding frequency was used as an index of deer herbivory. Palatable saplings showed high feeding frequency and became rare in deer-abundant areas, while unpalatable saplings showed low feeding frequency and increased with increasing deer density. In addition, feeding frequency on sapling vegetation did not continue to increase with increasing deer population and was limited to only 0.24-0.32 in deer-abundant areas (more than 20 deer/km2). These data suggest that deer shift their main food items from living palatable saplings to other alternatives such as litter fall rather than living unpalatable saplings. Clearly, the nonlinear relationship between deer density and deer herbivory on forest vegetation could result from a change in the food eaten by deer, and it is therefore necessary to assess the impacts of deer based on not only the size of the deer population but also the intensity of direct herbivory. 相似文献
997.
Charles Staver 《Agroforestry Systems》1989,8(2):173-196
In the Palcazu Valley alluvial Inceptisols are relay-cropped with maize-cassavaplantain in rotation with 2–5 years of tree
fallow. These lands, of limited extent, yet important for Yanesha Indian subsistence production, are being cropped even more
intensively as population increases and land is converted to other uses. The relay-planting of the tree-thicket combination
Inga edulis with Desmodium ovalifolium into the on-farm crop sequence was evaluated as a means to accelerate fallow recovery and thereby shorten fallow rotations.
Three experiments with Inga/Desmodium planted with cassava-plantain and one with rice under different weeding regimes after a Desmodium fallow were conducted. Inga and Desmodium were not chopped back or pruned during these experiments. Desmodium/Inga suppressed herbaceous weeds from one year after planting. Desmodium/Inga accumulated more woody biomass than natural fallows. Cassava yields were unaffected by the presence of Desmodium/Inga, while plantain yields were greater under Desmodium/Inga compared to natural weeds. Desmodium/Inga, while promising for shortening fallow rotations, demonstrated potential difficulties: increased labor for establishment,
tendency of Desmodium to weediness in later crop cycles, and suppression of the natural regeneration of trees and shrubs. 相似文献
998.
999.
麝类动物(Moschus spp.)雄性个体可分泌麝香,是濒危珍稀资源动物,驯养是濒危麝类动物的迁地保护(ex situ protection)和麝香生产的重要方式。我国从1958年开始麝类驯养,初期的主要驯养麝种为林麝(M.berezovskii),从1990年开始马麝(M.sifanicus)驯养。论文总结了濒危马麝的分群驯养,归纳了麝场选址、麝场修建、圈舍设计、分圈分群及日常驯养管理等方法体系,对我国麝类驯养、资源保育及麝香生产等提供重要参考。 相似文献
1000.
为确定母体状况对受胎的影响程度,并进一步提高梅花鹿的受胎率,应用分组比较卡方检验方法,对与母体状况相关且影响受胎的因素进行了研究。结果表明:与母体状况相关的年龄、膘情、产后发情时间及繁殖疾病都直接或间接地影响梅花鹿的受胎率;成熟健康的母体是提高受胎率的基本保证;梅花鹿繁殖配种应保证人工输精时年龄4岁,本交配种时年龄3岁,进入发情期时膘情7成,发情时间为产后120 d后,且无繁殖疾病。 相似文献