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101.
Nutrias(MyocastorcolIPus)isonekindofvaluablefuranimals.Functionofitsfurkeep-ing-temperatllfeisgoodandit'sakinisdurable,soitsskinandfurarcoftenusedasthemateri-alsoffurcoatandleather.Nutrianleatnotonlytastesdeliciousanddelicate,butalsocontainshighprotein.Nutriacanbefedeasilyanditsfeedingcostislow.Therefore,itisverysuitabletoourcountry.TherehasbeennoreportaboutstiJdyontl1enutritiverequirementofnutriasinChina.ThistestemphasizesonthepropernutTitivercquircll1entofnutfiaandithasprovidedsol1lebasi… 相似文献
102.
103.
饲粮不同能量、蛋白质水平对生茸期梅花鹿的影响 总被引:6,自引:2,他引:4
本研究采用 2 (CP:2 4和 2 2 % )× 2 (GE:4.1 5和 1 6.74MJ/kg)二因子交叉设计 ,选用1岁 (毛桃 )梅花公鹿 69头 ,分为四个试验组 ,进行了饲养试验和消化试验。试验结果表明 ,饲粮能量、蛋白质水平对鹿体增重的互作效应显著 (P<0 .0 5) ,饲粮粗蛋白质水平对蛋白质消化率有极显著的影响 (P<0 .0 1 )。 1岁梅花鹿生茸期饲粮中能量、蛋白质适宜水平分别为1 7.37MJ/kg GE、2 2 .44% CP。平均每头鹿每天对能量和蛋白质的需要量分别为 36.84MJGE和 478g CP 相似文献
104.
AIM:To study the effect of intestinal endotoxemia(IETM) on hepatic energy metabolism in acute liver failure. METHODS:Intoxication by thioacetamide (TAA) was used to establish rat model of acute liver injury.Ketone body(acetoacetate and β-hydroxybutyrate) in arterial blood and ATP content of hepatocellular mitochondria were determined by using enzymatic fluorimetric micromethod.Colectomy was adopted in observing the changes in plasma endotoxin content and serum alanine aminotransferase (ALT) activity. RESULTS:In the TAA group,plasma endotoxin content and serum ALT activity were all significantly higher than those in the control group(P<0.01),arterial ketone body ratio of acetoacetate to β-hydroxybutyrate (AKBR) decreased below 0.4,total ketone body in arterial blood was significantly lower than that in the control group(P<0.01).In the TAA+colectomy group,there was no endotoxemia to be found,ATP content of hepatocellular mitochondria was significantly higher than that in the TAA group(P<0.01), though serum ALT activity was higher than that in the control group(P<0.05),but significantly lower than that in the TAA group(P<0.01). CONCLUSION:IETM played a key role in the occurrence of acute liver failure,hepatic dysfunction might be caused by IETM through damaging hepatic energy metabolism. 相似文献
105.
AIM: To study the effect of mild hypothermia on energy metabolism and hydroxyl radical production as well as delayed neuronal death (DND) in hippocampus during cerebral ischemia/reperfusion in gerbils.METHODS: Forebrain ischemia was induced by occluding bilateral common carotid arteries with aneurysm clamps for 10 min in gerbils. The DND in hippocampal CA1 sector was assessed by histological examination, and hydroxyl radical, ATP (adenosine triphosphate), ADP (adenosine diphosphate),AMP (adenosine monophosphate) levels were determined by high performance liquid chromatography with electrochemical or ultraviolet detection. RESULTS: The number of survival neuronal in hippocampal CA1 sector in mild hypothermia + I/R group was more than that in I/R group after ischemia/reperfusion 96 h. The content of 2,3-DHBA (2,3- dihydroxybenzoic acid) in hippocampus in I/R group was much higher than those in sham operation and mild hypothermia + I/R group after reperfusion 6 h (P<0.01), but there were no significant differences in 2,3-DHBA outputs among 3 groups 48 h and 96 h after reperfusion. There were no obvious differences in ATP, ADP, AMP level in hippocampus among 3 groups 6 h after reperfusion. However, the content of ATP,ADP,AMP in mild hypothermia + I/R group was much higher than those in I/R group 48 and 96 h after reperfusion (P<0.01).CONCLUSION: Mild hypothermia can reduced DND by improving the cerebral energy metabolism during forebrain ischemia/reperfusion in gerbils. 相似文献
106.
用6头约克夏和10头汉普夏、杜洛克、丹麦伦德瑞斯共36头小公猪,在其20—100kg 生长阶段内分期进行氮—碳平衔试验和呼吸测热试验各180头次。结果表明,生长公猪每千克代谢体重(W~(0.75))所需的维持能量与体重的一定的幂的倒数成比例。当代谢能转化为体蛋白质能和体脂肪能的效率[k_p和k_f]为0.60和0.80,0.68和0.75,0.56和0.74时,每千克代谢体重所需的维持能量分别为1131W~(-0.20),1307W~(-0.23)和1235W~(-0.25)千焦代谢能或1173W~(-0.20),1356W~(-0.23)和1281W~(-0.25)千焦消化能。建议用 ME_m,KJ/W~(0.75),kg=1307W~(-0.23),kg 作为生长公猪维持需要的公式。 相似文献
107.
By means of calorimetry measurement,the caloric values of various components,the standing crop of energy,not energy production and energy conversing efficiency of an artifi-cial dahurian larch community at Laoshan Plantation Experimental Station of Maoer Shan For-est Farm in the eastern part of northeast China were determined and studied in the present paper.The result of the experiment were as follows:(1)caloric value varied with plant species and plant organs,in general,the order of caloric value was tree,shrub and herb,and for different organs,was leaf, branch,trunk(stem),bark and root.(2)The standing crop of energy of larch community and tree layer were 269.719×10~(10)J/ha.and 264.440×10~10J/ha.respectively.Theree xisted different distributions of energy in various components and different layers.(3)Net ener-gy prduction of larch community and its tree layer were 264.346×10~8J/ha.a and 243.678×10~8J/ha.a respectively.To the photosythetical active radiation on the stand,its energy con-versing eff 相似文献
108.
通过能值分析方法,对泸州市2002~2007年生态经济系统的能值投入率、能值使用强度、环境负荷率、人均能值使用量、电力能值使用量比、净能值产出率、可持续发展指数7个能值指标进行了定量分析。结果表明,泸州市的可持续发展处于一个不稳定的状态,在经济上较依赖于本地资源。虽然人民生活水平在不断提高,但较发达地区还有一定差距,泸州市在经济发展水平方面仍属于欠发达水平,还有较大的经济发展潜力。 相似文献
109.
110.
基于对因资源开发而兴盛的新兴资源型城市的整体认识,以陕北榆林为例,结合相关统计数据资料,指出其资源开发利用中存在的问题,主要在于能源产业结构单一,能源开发浪费严重;产品精深加工不够,资源综合利用水平较低;区域生态环境恶化。在此基础上,从微观、中观、宏观3个层面提出了资源型城市景观生态构建的新模式,强调从微观层面建立新型绿色能源产业发展模式,从中观层面构建循环经济的生态工业园模式,在宏观层面建立矿区整体生态恢复模式。以期对新兴资源型城市的可持续发展具有重要的启发意义。 相似文献