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31.
体外产气法评价青海高原反刍家畜常用粗饲料组合效应   总被引:1,自引:0,他引:1  
采用体外产气法评价青海高原反刍家畜的3种常用粗饲料青贮玉米(Zea mays)秸秆、苜蓿(Medicago sativa)青干草和燕麦(Arrhenatherum elatius)青干草按0∶100、25∶75、50∶50、75∶25和100∶0的比例两两组合时的发酵特性。结果表明,理论最大产气量、48 h产气量分别与中性洗涤可溶物/粗蛋白(NDS/CP)(P<0.001)、有机物(OM)(P<0.01),中性洗涤可溶物(NDS)(P<0.05)呈正相关关系,分别与酸性洗涤纤维(ADF)(P<0.001)、中性洗涤纤维(NDF)(P<0.05)和粗蛋白(CP)(P<0.05)呈负相关关系;产气速率常数分别与OM(P<0.001)、NDS(P<0.001)和NDS/CP(P<0.01)呈正相关关系,分别与ADF、NDF均呈极显著负相关关系(P<0.001);产气延滞时间与ADF(P<0.01)和NDF(P<0.05)呈正相关关系,分别与OM(P<0.01)、NDS(P<0.05)和NDS/CP(P<0.05)呈负相关关系,说明了组合牧草体外发酵产气程度主要受非结构性碳水化合物与粗蛋白比例的影响。3种粗饲料两两组合搭配时,青贮玉米秸秆与苜蓿青干草以25∶75比例、青贮玉米秸秆与燕麦青干草以50∶50比例、苜蓿青干草与燕麦青干草以25∶75或50∶50比例组合时较为合适,且随着发酵时间的延长,各组合均呈现组合效应量逐渐减弱的变化趋势。  相似文献   
32.
Objective – To establish the efficacy of Oxyglobin (HB-200) in canine babesiosis and compare it to standard therapy, packed red blood cell transfusion (pRBCT) with respect to improvements in specific parameters of blood gas, acid-base, blood pressure, and subjective evaluations.
Design – Prospective, randomized, clinical trial.
Setting – Onderstepoort Veterinary Academic Hospital.
Animals – Twelve dogs (8–25 kg) naturally infected with Babesia rossi and a hematocrit of 0.1–0.2 L/L (10–20%).
Interventions – Treatment groups were randomized to receive either 20 mL/kg of Oxyglobin or pRBCT over 4 hours via a central venous catheter. Transfusions were followed by lactated Ringer's solution infusion. Rectal temperature, femoral arterial and mixed venous blood sampling, oscillometric blood pressure, and subjective assessment of patient status (habitus), and appetite were performed at time points 0, 1, 4, 8, 24, 48, and 72 hours.
Main Results – Dogs presented with a hypoalbuminemic alkalosis; hyperchloremic, dilutional acidosis; normotensive tachycardia; pyrexia; depression; and anorexia. Both treatments produced similar results, with the exception of significant differences in pH (4 h); PCO2 (4 h); hemoglobin (8 h, 24 h); mean arterial pressure (48 h); albumin (4 h, 8 h); habitus (8 h, 48 h); and appetite (24 h). Arterial O2 content was higher for pRBCT than Oxyglobin at 72 hours, but central venous PO2 did not differ between groups or over time and was consistently subnormal.
Conclusions – Oxyglobin provides similar overall improvements to pRBCT in dogs with anemia from babesiosis, with respect to blood gas, acid-base and blood pressure, although patients receiving packed cells tended to have more rapid normalization of habitus and appetite.  相似文献   
33.
It has often been claimed that non‐carbon dioxide greenhouse gases (NCGGs), such as methane, nitrous oxide and fluorinated greenhouse gases, are significant contributors to climate change. Here we nvestigate emission estimates of methane and nitrous oxide from livestock and poultry production, which is recognized as a major source of those NCGGs, in Korea over the period of 1990 through 2010. Based on the data on livestock and poultry populations, emission estimates of methane and nitrous oxide are first derived based on the Tier 1 approach. Then, the Tier 2 approach is adopted to obtain emission estimates of methane and nitrous oxide from cattle, which are known to be the largest sources of these NCGGs and account for about 70% of emissions from livestock and poultry in Korea. The result indicates that the Tier 2 estimates of methane and nitrous oxide emissions from enteric fermentation and manure management are significantly different from the Tier 1 estimates over the analysis period.  相似文献   
34.
为探究三江源区不同季节放牧草场天然牧草营养供给潜力和载畜量,选用3头安装永久性瘤胃瘘管的成年大通牦牛为瘤胃液供体动物,采用概略养分分析法和体外产气法,结合产草量对放牧草场牧草进行综合评定并确定其载畜量。结果表明,1)夏、秋及冬春放牧草场的可食风干草的最高产量分别为(123.83±17.88),(256.88±29.90)和(246.83±66.73) g/m2。2)夏、秋及冬春草场天然牧草的最高粗蛋白(CP)含量分别为(12.69±0.13)%,(10.54±1.22)%和(8.65±0.64)%,其含量随牧草生长而逐渐降低;夏、秋及冬春草场天然牧草EE的最高含量分别为(2.95±0.10)%,(4.38±0.17)%及(3.74±0.70)%;NDS含量的变化趋势与CP一致,而NDF和ADF含量的变化与CP相反,随牧草生长含量不断增加。3)体外发酵pH和氨氮浓度均在正常范围内;夏季草场牧草的48 h产气量、24 h产气估测消化能(DM)、代谢能(ME)和有机物质降解率(OMD)的最大值分别为(57.50±4.27) mL、(9.32±0.59) MJ/kg、(7.98±0.62) MJ/kg和(57.93±3.23)%;秋季草场牧草分别为(54.67±5.35) mL、(8.83±0.64) MJ/kg、(7.47±0.68) MJ/kg及(55.26±3.52)%;冬春草场牧草分别为(58.83±4.51) mL、(9.56±0.60) MJ/kg、(8.24±0.63) MJ/kg及(52.69±5.14)%。4)无补饲条件下,夏、秋及冬春天然放牧草场载畜量分别按数量载畜量、数量载畜量和DCP载畜量核算放牧科学,其最适载畜量分别为7.05,19.51和2.47 SU/hm2;有良好补饲情况下,夏、秋及冬春天然放牧草场载畜量按DCP载畜量、ME载畜量和ME载畜量核算放牧科学,其最适载畜量分别为14.85,29.00和5.03 SU/hm2。因此,三江源区牧草产量和品质季节性差异大,能-氮不平衡,通过补饲可以使夏、秋及冬春放牧草场的载畜量分别提高1.1,0.5和1.0倍左右,有利于促进当地畜牧业发展和生态保护。  相似文献   
35.
建立了乳与乳制品中20种邻苯二甲酸酯气相色谱-质谱联用仪分析方法.样品用正己烷提取后,采用DB-5MS(30m×0.25mm,0.25μm)石英毛细管柱分离,在进样口温度280℃,传输线温度280℃,离子源温度230℃条件下20种邻苯二甲酸酯完全分离.该方法各组分的相关系数均大于0.9990,线性范围0~10μg/mL,样品加标回收率为80%~109%.邻苯二甲酸二异壬酯、邻苯二甲酸二异癸酯化合物检出限分别为1.0、0.5mg/kg,其他化合物均为0.05mg/kg.该方法具有简单易行,快速准确,灵敏度高等优点.  相似文献   
36.
ObjectiveTo compare the effects of two fractions of inspired oxygen (FiO2) (0.4 and 1) on lung aeration and gas exchange during general anaesthesia in cats.Study designRandomized, blinded, controlled study.AnimalsThirty healthy, mixed breed, client owned female cats.Materials and methodsCats were premedicated intramuscularly with acepromazine (0.03 mg kg?1) and medetomidine (0.015 mg kg?1). Anaesthesia was induced with propofol (5 mg kg?1) and, after orotracheal intubation, maintained with isoflurane carried by either 100% oxygen (G100, n = 15) or an oxygen-air mixture with 40% oxygen (G40, n = 15). All cats were placed in dorsal recumbency and breathed spontaneously throughout the entire procedure. Following surgery (ovariectomy), a spiral computed tomography (CT) of the thorax was performed, arterial oxygen (PaO2) and carbon dioxide (PaCO2) tensions were measured and alveolar-arterial gradient of oxygen [P(A-a)O2] calculated. The CT images were analysed for lung aeration by the analysis of radiograph attenuations (Hounsfield units, HU), according to the following classification: hyperinflated area (-1000 to -900 HU), normally aerated area (-900 to -500 HU), poorly aerated area (-500 to -100 HU) and non-aerated area (-100 to +100 HU). The groups were compared using one-way anova.ResultsCompared to G100, the normally-aerated lung area was significantly greater and the poorly-aerated and non-aerated areas were significantly smaller in G40. PaCO2 was similar in both groups. PaO2 and P(A-a)O2 were significantly higher in G100. In both groups, pulmonary atelectasis developed preferentially in the caudal lung fields.ConclusionIn cats anaesthetised with isoflurane, the administration of an FiO2 of >0.9 significantly impaired lung aeration and gas exchange as compared to an FiO2 of 0.4.Clinical relevanceAn FiO2 of 0.4 may better preserve lung aeration and gas exchange in anaesthetised spontaneously breathing cats but monitoring is essential to ensure oxygenation is adequate.  相似文献   
37.
【目的】研究两种通风模式下杭州地区规模化猪场舍内环境参数及其分布规律,筛选出适合本地区推广的通风模式。【方法】选取杭州地区具有代表性的横向通风和纵向通风两种通风模式下育肥舍为研究对象,开展了早、中、晚3个不同时间点,进风口、舍中央和排风口3个不同位置的热环境参数、有害气体浓度的监测,持续监测1周。分析不同时间点和舍内不同位置对热环境参数(温度、相对湿度、风速)以及有害气体(氨气(NH3)和硫化氢(H2S))浓度的影响,并对两种模式下的热环境参数及有害气体浓度进行比较分析;采用空气沉淀法收集舍内环境中的细菌,并对细菌进行培养及统计分析,比较两种模式下育肥舍中细菌数量差异。【结果】两种通风模式下育肥舍相对湿度均低于国家标准,位置和各时间点对相对湿度影响不大,其中纵向通风舍内的相对湿度显著高于横向通风模式(P<0.05)。两种通风模式舍内平均温度没有显著性差异(P>0.05),舍内中午温度显著高于早、晚(P<0.05),位置对纵向通风舍内温度影响较大。纵向通风舍内平均风速为(1.09±0.42)m/s,符合国家标准且极显著高于横向...  相似文献   
38.
内标法同时测定挥发性脂肪酸和乳酸的方法探究   总被引:1,自引:0,他引:1  
选用巴豆酸作为内标物,以内标标准曲线法定量,探讨无需任何前处理便能同时测定挥发性脂肪酸和乳酸的最佳色谱条件。用HP-INNOWAX(19091N-133)毛细管柱,以高纯氮作为载气,用氢火焰离子化检测器对挥发性脂肪酸和乳酸进行测定。结果表明:其理想检测条件为载气总压力160kPa,气化室温度250℃,检测室温度270℃,柱温采用程序升温法,初始温度120℃,然后以10℃/min升温速率升至220℃,保持2min。  相似文献   
39.
完熟金煌芒果实香气成分研究   总被引:1,自引:0,他引:1  
采用顶空固相微萃取技术和气相色谱-质谱联用仪对完熟金煌芒果实的香气成分进行初步研究,结果表明,共检出22种香气成分,主要的香气成分有E-3-溴-2,6,10,15,19,23-六甲基-6,10,14,18,22-十一碳五烯-2-醇(相对含量20.57%),3-蒈烯(相对含量11.50%)等;主要的香气类型有醇(相对含量25.76%),酸(相对含量24.42%),萜烯类(相对含量18.18%)等。  相似文献   
40.
基于G1赋权法的油气管道应急预案质量评价   总被引:2,自引:1,他引:2  
在构建油气管道应急预案质量评价指标体系的基础上,鉴于常见的层次分析法(AHP)对指标赋权所存在的不足,采用G1法对各个指标进行权重赋值,给出了应急预案质量评定分值的求取方法、评判等级划分及其不同的应急预案质量完善策略。研究结果对如何评价油气管道应急预案的质量提供了方法指导,同时对应急预案的维护与修订提供了决策支持。  相似文献   
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