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1.
水资源是人们赖以生存的资源,其不但可以给人们提供生活用水,还可以利用水能资源进行发电,从而保证水电站的稳定运行。随着社会的不断发展,我国水资源出现了紧缺的现状,由于水资源属于不可再生的资源,所以,一定要科学合理的利用水资源,还要避免出现资源浪费等问题,实现水资源利用的最大化。本文对科学发展观指导水能资源的科学利用进行了分析,希望对相关工作者提供一定帮助,加强对水能资源的开发与利用,实现可持续发展。  相似文献   

2.
土地利用现状资料是编制土地利用总体规划的可靠依据,为正确的领导决策提供了可靠的信息资源。本文在对酉阳县土地利用现状数据变化全面分析的基础上,指出了该县现有土地利用现状存在的问题和矛盾,并以此对酉阳县土地利用的发展趋势进行了科学的预测,为后期的规划修编工作提供了可靠的数据基础,具有一定的应用价值。  相似文献   

3.
猪栏舍的设计建造,构成了猪场的最大固定投资成本。因此,对猪栏舍的合理利用,是确保养猪经济效益的前提。刘继军等对猪场的生产工艺流程进行了划分,陈国宇则对各类猪栏数的计算进行了介绍。本文根据养猪生产工艺流程的不同提出了各类猪栏数的确定方法,并在此基础上对现有猪舍的合理利用进行研究,旨在合理而充分地利用各类猪舍,使养猪的效益达到最优化。  相似文献   

4.
本文综述了奶牛日粮淀粉的消化吸收位点对其利用影响的研究进展,重点介绍了日粮淀粉在奶牛瘤胃、小肠中的消化吸收,日粮淀粉的转化利用及淀粉消化位点对淀粉利用的影响。  相似文献   

5.
从草地资源的特点、利用与生产现状等方面进行了总结,分析了存在的主要问题,并提出了可持续利用的措施和对策,对因地制宜地开发和利用草地自然资源,促进当地畜牧业生产的持续、稳定发展。  相似文献   

6.
本文对扎兰屯市天然草地利用现状进行了详细分析,根据利用情况将其划分为草地超载退化区,畜草基本平衡区,少畜富草区,对不同草地的利用提出了具体措施。  相似文献   

7.
近年来,张掖市积极探索养殖业废弃物无害化利用方式,取得了一定的成效。本文通过对废弃物治无害化利用现状的分析,提出了的相关建议。  相似文献   

8.
皮蛋是具有中华民族饮食文化典型特征的传统食品,随着皮蛋加工量的不断扩大,皮蛋腌制液也越来越多。皮蛋腌制液的循环利用能减少对环境的污染,更能降低皮蛋的生产成本,提升经济效益,还能促进行业的转型升级。文章在详细介绍皮蛋腌制液循环利用、循环腌制过程中腌制液成分变化基础上,综述了皮蛋腌制液循环利用工艺与设备研究进展,并对皮蛋腌制液循环利用的发展方向提出了建议。  相似文献   

9.
采用综合分析法和文献综述法,对城市土地优化配置和集约利用的内涵进行了解释,归纳总结了用于城市土地优化配置与集约利用评价模型,以期在城市土地优化配置与集约利用中得到应用,并逐步改进。  相似文献   

10.
本文对目前国内外利用乳公犊的不同方法进行了剖析,探讨了我国利用乳公犊生产牛肉存在的一些问题,同时,结合我国国情,提出了一些利用乳公犊资源的新思路。  相似文献   

11.
2年的牦牛放牧试验表明:除不同植物本身的生理特性外,降水和地温是影响小嵩草高寒草甸两季草场不同植物类群地上生物量绝对生长率的关键因素。小嵩草高寒草甸两季草场地上总生物量的绝对生长率1999年在7月份最大;1998年,冷季草场各放牧处理的绝对生长率在8月份达到最大,暖季草场的对照组和轻牧组在7月份最大,中牧组和重牧组在8月份最大。不同植物类群地上生物量生长率的变化不尽相同。1998年,冷季草场禾草和莎草地上生物量的绝对生长率8月份达到最大,暖季草场禾草和莎草地上生物量的绝对生长率7月份达到最大,且9月份出现了营养的再次积累;1999年,冷季草场禾草地上生物量的绝对生长率在6月份和8月份出现了两个峰值,暖季草场禾草地生物量的绝对生长率在7月份达到最大。对杂草类而言,1998年冷季草场的绝对生长率6月份最大,暖季草场重牧组的绝对生长率8月份达到最大,其他各处理7月份达到最大;1999年重牧组杂草的绝对生长率在6月份达到最大,其他各处理杂草在8月份达到最大。  相似文献   

12.
为更有效地防治内蒙古自治区四子王旗地区家畜微量元素代谢病,合理使用微量元素添加剂,采用实地采样和实验室分析相结合的方法,对该地区短花针茅(Stipa breviflora)荒漠草地土壤-牧草-家畜生态系统中微量元素的水平进行检测。结果显示,土壤中铜和硒处于缺乏状态。牧草中铁和锰元素处于过量状态,硒为缺乏状态。与健康绵羊的各项指标相比较,血浆中铁和锰分别于夏秋季节和全年高于正常水平,硒和铜元素分别于秋季和冬季低于正常水平;肝脏中铁和锰全年高于正常水平,铜冬季低于临界值,硒元素秋冬季节低于正常水平;被毛中铁全年高于正常水平,而铜和硒全年低于正常水平。结合放牧绵羊对各种矿物质的进食量和消化率进行综合分析表明,该地区为高铁、高锰、低硒的生态环境,同时铜和锌处于季节性缺乏状态。  相似文献   

13.
The effects of intravenously administered thiomolybdate on the liver and kidney of copper loaded sheep were studied using 16 ewes in three groups. Copper, iron and molybdenum concentrations were determined by spectrophotometry and the distribution of copper in the liver and kidney was studied histochemically. Following thiomolybdate administration, the concentration of copper in the liver was reduced, that of molybdenum increased and the concentration of copper and molybdenum in the kidney increased. The reduction of copper concentration in the liver was associated with reductions in the number and size of granules in hepatocytes which stained positively for copper and in the number of Kupffer cells containing positively staining granules. The decrease in the amount of copper in hepatocytes appeared to be greater than that in Kupffer cells. This effect was greatest in the centrilobular zones and least in the periportal zones. The increased concentration of copper and molybdenum in kidney was associated with an increase in the number and size of granules staining positively for copper in the epithelial cells of the proximal convoluted tubules which suggested an uptake of copper-molybdenum complexes by the lysosomes of these cells.  相似文献   

14.
Campylobacter spp. have been identified as etiologic agents in outbreaks and sporadic cases of gastroenteritis in developed countries. In developing countries, most reported Campylobacter infections are in children. Previously reported prevalences of Campylobacter spp. in children in Southeast Asia range from 2.9% to 15%. The frequency and pattern of occurrence of Campylobacter spp. differ between developed and developing countries, especially in the number of cases reported in adults and the presence of any seasonal patterns in occurrence. Although the severity of Campylobacter infection in adults was different between developed and developing countries, the clinical symptoms of infection in adults resulting from infection in developing countries was similar to those in developed countries. Many different animal species maintain Campylobacter spp. with no clinical signs. There do not appear to be significantly different colonization rates of Campylobacter in food animals between developed and developing countries. The role of C. jejuni as a primary pathogen in farm animals is uncertain. C. jejuni can be found in feces of diarrheic and healthy calves and piglets. Campylobacter with resistance to antimicrobial agents have been reported in both developed and developing countries, and the situation seems to deteriorate more rapidly in developing countries, where there is widespread and uncontrolled use of antibiotics resistance was observed at high levels in food animals in both developed and developing countries. Studies suggested an association between antimicrobial use in food animals and the development of resistance in human isolates in developed countries.  相似文献   

15.
中国野生动物驯养与繁殖法律制度的缺陷与完善   总被引:1,自引:0,他引:1  
陈春艳 《野生动物》2006,27(1):53-56
野生动物驯养繁殖在世界野生动物资源保护中具有重要作用,有关野生动物驯养繁殖的法律制度也成为各国野生动物资源保护立法的主要内容。本文针对目前中国野生动物驯养繁殖的立法现状与存在问题,提出完善中国野生动物驯养繁殖的国内法对策,以推进中国野生动物资源保护立法的发展。  相似文献   

16.
羔羊小肠pH及主要消化酶发育规律的研究   总被引:13,自引:2,他引:13  
对小尾寒羊羔羊小肠不同部位(十二指肠、空肠和回肠)pH及淀粉酶、胰蛋白酶、糜蛋白酶、脂肪酶和乳糖酶的活性进行了测定,结果表明:羔羊小肠不同部位内容物pH不同,回肠pH显著高于空肠,空肠和回肠pH显著高于十二指肠,羔羊1月龄后,小肠各段pH变化不大;小肠不同部位淀粉酶和胰蛋白酶、糜蛋白酶及脂肪酶活性不同,空肠段淀粉酶、胰蛋白酶、糜蛋白酶及脂肪酶活性高于十二指肠和回肠段,随着羔羊日龄的增长,小肠淀粉酶、胰蛋白酶、糜蛋白酶及脂肪酶活性增加,3月龄后各消化酶活性变化差异不显著(P<O.05);羔羊小肠不同部位乳糖酶活性不同,空肠乳糖酶活性显著高于十二指肠和回肠,随着羔羊日龄的增长,小肠乳糖酶活性逐渐降低。  相似文献   

17.
本试验旨在测定我国四川、山东、河北省(包括京津冀地区)蛋鸡养殖场产蛋高峰期配合饲料中镉(Cd)、铬(Cr)、铅(Pb)含量,评估蛋鸡养殖大省3种重金属污染程度。采集四川、山东、河北省67个养殖场268份蛋鸡配合饲料,采用高分辨率连续光源火焰原子吸收光谱法(HRCS FAAS)测定其Cd、Cr、Pb含量。结果表明:1)四川省蛋鸡配合饲料中Cd、Cr、Pb含量最大检出值所在城市分别为成都、乐山、乐山,最大检出值分别为0.48、15.94、14.12 mg/kg;Cr、Pb含量最高超标率所在城市分别为乐山、崇州,超标率分别为30%、50%。2)山东省蛋鸡配合饲料中Cd、Cr、Pb含量最大检出值所在城市分别为青岛和日照、菏泽、日照,最大检出值分别为0.45、5.88、4.11 mg/kg。3)河北省蛋鸡配合饲料中Cd、Cr、Pb含量最大检出值所在城市分别为张家口、张家口、保定,最大检出值分别为0.45、15.38、8.38 mg/kg;Cr、Pb含量最高超标率所在城市分别为张家口和保定,超标率均为20%。4)3省蛋鸡配合饲料中Cd、Cr、Pb平均含量分别为,四川:0.24、5.01、3.67 mg/kg;山东:0.26、4.19、2.61 mg/kg;河北:0.25、5.66、3.25 mg/kg。参照我国《饲料卫生标准》,3省蛋鸡配合饲料中Cd含量及山东省Cd、Cr、Pb含量均未超标;四川、河北省Cr、Pb含量超标率分别为9.38%、17.19%和6.73%、14.42%。5)河北省蛋鸡配合饲料中Cr、Pb平均含量显著高于山东省(P0.05);大规模养殖场配合饲料中Cd、Cr、Pb平均含量显著低于小规模养殖场(P0.05)。综上所述,山东省蛋鸡配合饲料中Cd、Cr、Pb含量均未超标。四川、河北省蛋鸡配合饲料中Cd含量未超标,但有超标风险,Cr、Pb含量均有不同程度超标,Pb含量超标最为严重,应引起重视。  相似文献   

18.
奶牛发情周期中毛 唾液和乳汁孕酮水平的变化   总被引:1,自引:0,他引:1  
本实验采用放射免疫分析法(RIA)测定了11头奶牛一个发情周期里毛、唾液、乳汁中孕酮(P_4)含量。经产牛(n=8)的毛和唾液中P_4水平变化与乳汁中P_4水平变化一致。青年牛(n=3)的毛和睡液中的P_4水平变化一致,并分别与经产牛毛和唾液中P_4水平变化一致。7头配种后的经产牛和5头配种后的青年牛分别取20和23天的样品进行妊娠诊断,与配种后60天的直检结果相对照,依据经产牛毛、乳P_4水平进行妊娠诊断的阳性准确率分别是85.7%(6/7)和100%(7/7),依据青年牛毛P_4水平进行妊娠诊断的阳性准确率为100%(5/5)。  相似文献   

19.
Twenty-four dogs with a parasitologically and serologically established diagnosis of leishmaniasis were studied to investigate the atrophy of the masticatory muscles which commonly occurs in this disease, and to compare the lesions in the masticatory muscles with those in the cranial tibial muscles. The 24 animals were divided into three groups of eight, group A dogs with no muscular atrophy, group B dogs with different degrees of atrophy in the masticatory and skeletal muscles, and group C dogs with similar degrees of atrophy in the masticatory and skeletal muscles. Increased activities of creatine phosphokinase and lactate dehydrogenase were recorded in only some of the dogs in groups B and C, but there were no significant differences between the mean activities in the three groups. Electromyographic changes indicating myopathy and involving both the temporalis and cranial tibial muscles, were observed in two of the dogs in group A, seven of those in group B, and in all the dogs in group C. Muscle histopathology revealed a variable degree of muscle fibre necrosis and atrophy, mononuclear infiltrates and neutrophilic vasculitis in all the dogs except two in group A. Leishmanial amastigotes were found within macrophages and myofibres in 16 of the dogs, some in each group. IgG immune complexes were detected in muscle samples, and circulating antibodies against myofibres were detected in serum samples from all the 24 dogs.  相似文献   

20.
The species of pets owned in the Netherlands are constantly changing, and it is important that veterinary practitioners have information about the number and species of pets presented in veterinary practice. Using the same methodology as in 1994, we determined the relative importance of the various pet species in 2005 and compared these data with those for 1994. The most notable findings were a 25% increase in the number of birds and exotic animals seen in small and large animal practices (from about 10% to about 12.5%), a doubling of the number of birds and tripling of the number of pigeons seen in mixed practices, a doubling of the number of reptiles seen in small animal practices, and a 10-fold increase in the number of fish seen in veterinary practices in general. There was a significant decrease in the proportion of cats (from 46% to 40.7%) and an increase in the proportion of dogs (from 44% to 46.7%). These trends in veterinary practice consultations did not parallel those seen in pet ownership. The increase in the number of birds (especially pigeons), reptiles, and fish seen in veterinary practice emphasizes the need to pay attention to these species in the standard companion animal curriculum.  相似文献   

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