9种豆科牧草总黄酮和总皂苷积累规律的研究

黄酮和皂苷不仅是植物中重要的防御性次生代谢产物,而且具有显著的药理和生理活性,对于植物的抗性研究和工业化应用具有重要意义。对鹰嘴紫云英(Astragalus cicer L.)、红豆草(Onobrychis viciaefolia Scop)、百脉根(Lotus corniculatus L.)、小冠花(Coronilla varia L.)、黄花草木樨(Melilotus officinalis(L.)Desr.)和苜蓿(Medicago L.)多种豆科牧草中总黄酮和总皂苷的周年积累规律和分布特点进行研究,以期为豆科牧草建立科学的牧刈制度和合理应用提供理论依据。结果表明:总黄酮和总皂苷在不同属间和品种间的动态变化各不相同;在不同组织中的分布也不同,在整个生育时期,均为叶片中的含量多于茎秆中的。前5种豆科牧草的总黄酮含量显著高于苜蓿,是提取总黄酮的优质材料;红豆草、鹰嘴紫云英、黄花草木樨及苜蓿的总皂苷含量均高于小冠花和百脉根,是提取皂苷产品的优质材料。     

放牧强度对高寒混播人工草地土壤氮、磷、钾含量的影响

垂穗披碱草/星星草混播草地三个放牧季的牦牛放牧试验结果表明:①随放牧强度的提高,各土壤层全氮和全钾含量出现了"高—低—高"的变化趋势,0~10cm土壤层全磷含量的变化趋势与之相反,而10~20cm和20~30cm土壤层上的变化趋势与全氮和全钾相似;②放牧强度对各土壤层全磷、全氮和全钾含量的影响分别为不显著(P>0.05)、显著(P<0.05)和极显著(P<0.01)。     

灰绿藜形态性状与繁殖性状的异速关系

通过对不同光照强度、营养和萌发时间处理条件下灰绿藜的形态指标和繁殖指标的测定,本研究探讨了灰绿藜形态性状和繁殖性状之间的异速关系及其异速生长对环境变化的响应。结果表明:灰绿藜形态性状与繁殖性状之间存在显著的异速生长关系,随着灰绿藜个体大小的增大,单个枝条的大小增速更快,并且将更多的资源分配到灰绿藜的繁殖生长。但灰绿藜的花序密度与个体大小之间具有显著的权衡关系:灰绿藜越小,花序密度越高。光照处理引起植物的繁殖性状发生了变化,但是这些变化主要是由在光照梯度下的个体大小不同造成的,繁殖策略(异速生长)未发生改变。而营养及萌发时间处理对灰绿藜的形态性状与繁殖性状间的异速关系产生了影响。营养变化对不同性状间的异速关系无一致影响,而萌发时间则具有显著的影响,晚萌发的灰绿藜将更多的资源投入到繁殖生长。     

规模化奶牛场产奶牛和育成牛粪中污染因子的四季动态监测研究

本研究对规模化奶牛场产奶牛和育成牛粪中污染因子进行了四季监测,结果表明,鲜粪中含水率两类牛群夏季最高、春季最低;风干粪样中,除产奶牛夏季全氮和全磷外,产奶牛和育成牛5项检测指标及其年均值的季节变化规律均保持一致,即有机质＞全氮＞全磷＞锌＞铜;两类牛群全磷含量夏季最高、秋季最低,有机质含量春季最高、夏季最低,铜和锌含量夏季均最低;产奶牛全氮含量夏季最低、春季最高,铜含量春季最高,锌含量冬季最高;育成牛全氮含量夏季最高、秋季最低,铜含量秋季最高,锌含量春季最高.     

奶牛养殖小区育成牛粪中污染因子的四季动态监测研究

本文研究了奶牛养殖小区育成牛粪中污染因子的季节变化规律,结果表明,育成牛鲜粪中含水率春季最低,冬季最高;风干粪样中,除夏季全氮和全磷顺序颠倒外,五项检测指标及其年均值的季节变化规律均保持一致,即有机质〉全氮〉全磷〉锌〉铜;育成牛全氮含量夏季最低、冬季最高,全磷含量秋季最低、夏季最高,有机质含量夏季最低、秋季最高,铜含量夏季最低、春季最高,锌含量春季最低、夏季最高。     

Technical and Economic Effects of Culling and Reproduction Strategies in Dairy Cattle Herds Estimated by Stochastic Simulation

Abstract

The objective of this study was to create operational replacement guidelines under various conditions concerning reproductive performance, supply of replacement heifers and individual milk yield. Nine culling strategies were defined by three average insemination periods and by three discrimination policies between high- and low-yield cows. The effect of the nine culling strategies was analysed with combinations of heat detection rate and time of initiation of breeding after calving under two replacement heifer purchase policies: purchase (open herd) and no purchase (closed herd). The strategies were evaluated using a stochastic simulation model that simulated production and reproductive status in herds composed of dual-purpose cattle with additional young stock. The evaluation of the strategies was made in a situation without a milk quota under typical Danish conditions in 1993. Results showed that discriminating between high- and low-yield cows improved net revenue significantly in open herds but not in closed herds. Irrespective of the purchase policy, using longer insemination periods increased net revenue significantly in herds with poor reproductive performance; whereas net revenue in herds with good reproductive performance tended to increase by using shorter insemination periods. The culling rate is a poor figure when evaluating culling strategies and culling strategies should be assessed at herd level rather than per cow.     

冷地早熟禾总非结构碳水化合物的季节动态

采用酸提法和水提法两种不同的提取方法对冷地早熟禾的总非结构碳水化合物(TNC)的季节动态进行了研究,同时进行了强度刈割试验以观测TNC与再生的关系。结果显示:冷地早熟禾的TNC季节变化呈宽“U”型,两种提取方法的TNC在返青后都有一个明显的下降过程,酸提TNC在开花期为最低点,水提TNC则是在抽茎期。抽穗期刈割对植株体的再生高度和分蘖数影响最大,而TNC和再生之间并未显示出显著的正相关关系。     

不同茧色家蚕品种茧层中的酚类物质含量及抗氧化活性分析

家蚕茧层中因含有黄酮类和其它酚类物质而具有抗氧化活性,被广泛用作化妆品和保健织物生产的原材料。对10个彩色茧家蚕品种和4个白茧家蚕品种茧层提取液中的酚类物质含量及体外抗氧化活性进行测定,并分析其量效关系,为筛选茧层中富含多酚类物质的家蚕品种及建立快速简便的茧层提取物抗氧化活性评价方法提供参考。不同茧色家蚕品种茧层中的酚类物质含量和茧层提取液的抗氧化活性存在明显差异:以绿茧品种最高,平均总多酚质量比为12.756 mg/g,其中总黄酮质量比为1.920 mg/g,总抗氧化活性达294.285 U/g,DPPH自由基清除率为48.583%;白茧品种最低,平均总多酚质量比为1.175 mg/g,其中总黄酮质量比为0.352 mg/g,总抗氧化活性仅有42.600 U/g,DPPH自由基清除率为17.258%;金黄茧和红茧品种居中。不同茧色品种茧层提取液的体外抗氧化活性与其总多酚和总黄酮含量的相关性都达到极显著水平,揭示家蚕茧层中的酚类物质是其抗氧化作用的重要物质基础之一,可通过测定茧层总多酚和总黄酮的含量,评价不同品种茧层提取液的抗氧化活性。     

Use of Total Parenteral Nutrition in Dogs: 209 Cases (1988-1995)

The medical records of 209 dogs receivingtotal parenteral nutrition (TPN) over a 84-month period were examined retrospectively to determine patient profiles, frequency and type of complications, and prognostic factors affecting clinical outcome. TPN administration accounted for 895 patient days. Dogs with diarrhea or vomiting associated with gastrointestinal disease, pancreatitis, or renal failure constituted the largest proportion of patient receiving TPN. The median duration of TPN administration was 3.5 days (range 0.05 to 25 days). The median length of hospitalization before initiation of TPN was 1.5 days (range 0.05 days to 15 days). and this durationwas not associated with survival. Metabolic complications were frequent (329 of 473 complications observed) and were due predominantly to hyperglycemia. Mechanical (118 of 473) and septic (26 of 473) complications occurred less commonly. The overall mortality rate for dogs receiving TPN was 48.8%. Our conclusion: TPN can be a beneficial mode of therapy for carefully selected dogs that have impaired gastrointestinal function (parvovirus, pancreatitis, or inflammatory bowel disease) and are expected to be anorectic for morethan 5 days.     

真胃变位奶牛抗氧化能力研究

为了阐明奶牛发生真胃变位(abomasal displacement,DA)时机体抗氧化能力的变化规律,本试验采用分光光度法对27头真胃左方变位奶牛与13头健康奶牛血浆总超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、总抗氧化能力(T-AOC)、丙二醛(MDA)含量进行了测定.结果 表明,与健康奶牛相比,...     

尿素精料和碱化秸秆在幼羊全混合日粮中的应用效果

选用 １２ 只两月龄东北细毛公幼羊，按体重大小随机分为 ４ 组，测定不同加工处理全混合日粮（ＴＭ Ｒ）对其生产性能的影响，并分析ＴＭ Ｒ饲养的经济效益。试验结果表明，在含玉米秸的ＴＭＲ 中以尿素精料等氮代替豆饼，在不降低幼羊生产性能的前提下（Ｐ＞ ０．０５），使每千克增重的饲料费用降低２６．４４％ ；在含尿素精料的 ＴＭＲ 中，玉米秸的碱化处理虽未显著影响幼羊的日增重及日采食 ＴＭ Ｒ 量（Ｐ＞ ０．０５），但却使ＴＭＲ 转化率提高了 ２１．５２％ （Ｐ＜ ０．０１），而且每千克增重的饲料费用降低 １１．２５％ ；对含尿素精料及碱化玉米秸的ＴＭＲ 进行颗粒化加工，与加工前相比，试羊日增重、日采食 ＴＭＲ 量及其转化率分别提高了 １６１．９２％ （Ｐ＜ ０．０１）、８８．７４％ （Ｐ＜ ０．０１）及２８．０１％ （Ｐ＜ ０．０１），每千克增重的饲料费用降低１７．６４％ 。     

缺氧条件下引入家兔血量的实验研究

在海拔3000m的西藏高原林芝，用间接测定法（T1824）对引入高原的加尼福尼亚兔、中国白兔和青紫兰兔的红细胞压积、血浆容积、红细胞容积、血液总量分别测定。结果表明，红细胞压积、血浆容积、血液总量在兔品种、兔性别之间具有引入时间先后和性别的差异性，而红细胞压积差异不明显，与低海拔家兔相比都有不同程度的增加，这对引入家兔适应高海拔、低氧分压的特定生态环境具有重要意义。     

西门塔尔杂交后备母牛日粮植物源磷进食量对表观可消化磷的影响

旨在采用消化试验研究后备母牛日粮植物源磷进食量与磷表观消化率的关系。试验选用体况良好、体重一致的西杂后备母牛[西门塔尔牛(♂)×中国黄牛(♀)]24头,随机分为6组,即试验1组、2组、3组、4组、5组和6组,每组4头,分别定量(3.50kg/d)饲喂6种不同磷水平的精料日粮,粗料(青贮)自由采食。使用麸皮调节日粮精料磷水平,各试验组精料磷水平分别为0.36%、0.40%、0.42%、0.46%、0.50%和0.54%;总试验期为30d,预饲期20d后进入正试期,试验最后7d全收集粪样和尿样。饲料样及粪样均测定其中磷和干物质含量,计算粪磷排泄量与日粮磷进食量的回归关系。结果表明,不同日粮处理间消化道磷的表观消化量和表观消化率有显著差异(P<0.05),并随进食磷量的增加而增加,但消化道表观消化的磷量与磷的进食不是直线关系,而是呈现抛物线关系,在日粮磷水平为0.42%时,消化量和消化率达最大,即分别为10.5g/d和40.8%。     

饲草型全混合日粮对羔羊肉品质的影响

为探讨不同配方饲粮饲喂羔羊时对其肉质的影响,选用巴彦淖尔市较为丰富的紫花苜蓿(Medicago sativa)、小麦(Triticum aestivum)秸秆、玉米(Zea mays)秸秆和番茄(Lycopersicon esculentum)渣等饲草资源,结合饲草GI分级指数和饲草组合效应理论,配制出羔羊育肥专用饲草...     

日全食家禽动物行为观察

对日全食时家禽动物行为进行观察,为家禽养殖及其动物行为学提供基础资料。观察日全食时放养鸡、鹅、番鸭、骡鸭及水鸭等家禽的动物行为学变化。结果:日全食时,家禽敏感程度为,鸡最敏感,番鸭次之,鹅第三,骡鸭和水鸭最不敏感。     

Abstract of Current Literature

Summary: Orthopaedic surgeons in many major arthroplasty centres advocate the use of a prolonged surgical hand-scrub prior to total joint replacement. In this study we evaluated the antimicrobial efficacy of a 5 compared with a 10 min scrub before both long (>90 min) and short (<90 min) operations for total hip arthroplasty. Surgical hand disinfection was performed on one occasion for 5 min and on a second for 10 min by 41 surgeons and theatre nurses using 4% chlorhexidine gluconate as a detergent formulation ('Hibiscrub', ICI Pharmaceuticals). None of the subjects had previously scrubbed on the day of each test. Bacterial colony counts on the fingers were measured using the method described by Rotter (vide infra) before scrubbing, immediately after scrubbing, and at the end of each operation. Our results showed that for arthroplasty procedures lasting less than 90 min (35 operations) a 5 min hand-scrub was equally as effective as one of 10 min. However, following longer procedures (36 operations) colony counts were significantly higher on subjects who had scrubbed for 10 min than on those who only scrubbed for 5 ( P < 0.05, Mann-Whitney U -Test). This study suggests that the practice of a prolonged scrub before total joint replacement does not have a scientific basis and that such a policy should be discontinued where it is still practised. © 1994 The Hospital Infection Society