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无角美利奴亲本母羊生产性能与血液生化指标的相关性 总被引:1,自引:0,他引:1
对87只无角美利奴亲本母羊的生产性能及其血液生化指标进行了测试分析,试验结果表明,毛长,毛密,体重与其血清无机磷,血清钙磷乘积,血清总蛋白,血清白蛋白、胆固醇、黄疽指数呈极显著正相关;与血清钠、胡萝卜素,a2球蛋白呈显著正相关;而与血清磨香草酚浊度呈极显著负相关;与硫酸锌浊度、血清谷草转氨酶活力呈显著负相关;与其年龄呈显著负相关。 相似文献
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Schultz WJ 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1987,16(3):67-72
A new technique by High Performance Liquid Chromatography (HPLC-gel permeation) shows promise as a tool to separate and quantitate the Unsaturated Vitamin B(12) Binding Capacity (UBSC) of the individual Vitamin B(12) binders in blood serum. This method, although not as rapid as protein-coated charcoal or cellulose separation techniques, is more applicable for use with large numbers of samples than gel filtration. The use of a radioactivity detector to monitor the eluant from the column permitted automation of the method. Comparable results for UBBC and for the UBBC of individual binders were obtained when samples were analyzed by gel filtration and HPLC. The HPLC method proved suitably precise and the recovery of added cyanocobalamin was acceptable. It is proposed that HPLC be the method of choice for measurement of the USBC of binders of Vitamin B(12) in blood serum. 相似文献
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《Livestock Production Science》2005,95(3):255-263
The aim of the experiment was to investigate the effects of cage floor and cage density on stress parameters of laying hens. A total of 162 brown laying hens (Hyline Brown), aged 34 weeks, were used in the experiment. Compact-type battery cages, with three floors, were used. Hens were allocated as one, three or five hens in each of 18 cages to obtain three different cage density groups of 1968, 656 and 393.8 cm2 floor area per hen, respectively. The same number of cages with different cage density were allocated to three different battery floors (first floor=top, second=middle, third=bottom) systematically. Values for body weight, mortality rate, egg weight, egg production, egg quality characteristics, egg yolk cholesterol content, the levels of blood plasma corticosterone, serum glucose, total cholesterol and triglycerides, the ratio of heterophils to lymphocytes (H-L ratio), antibody titers, claw length score, foot health score, plumage score and throat skin injuries were taken as indicators of stress. The values for egg weight (P<0.01) at the first floor were greater than the other floor levels. The group with five hens per cage had significantly lower mean estimates (P<0.01) than other groups with respects to body weight (P<0.001), egg production (P<0.001), egg weight (P<0.001) and plumage score (P<0.01), while significantly higher mean estimates for egg albumen index (P<0.01), Haugh unit (P<0.01), serum glucose (P<0.001), and H-L ratio (P<0.001). Serum cholesterol was higher in cages with one hen than that with five hens, whereas plasma corticosterone was lower. Antibody titers in cages with one hen was similar to that with three or five hens; however, those with three hens had higher titers than those with five hens. Values for egg breaking strength, yolk index, egg cholesterol content, and foot health score were not affected by cage density or floor. The results suggest that the allocation of three hens per cage had no measurable effect on health and welfare. 相似文献
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三元杂交牛12和18月龄肉用性能研究 总被引:4,自引:1,他引:4
选择健康无病、发育正常、膘情中等的夏洛来×西门塔尔×本地牛(夏西本)、皮埃蒙特×西门塔尔×本地牛(皮西本)、利木赞×西门塔尔×本地牛(利西本)、西门塔尔×西门塔尔×本地牛(西杂二代)各10头,从6月龄开始育肥,测定其增重、饲料消耗及其12和18月龄的屠宰成绩。结果表明:平均日增重以皮西本、利西本较高,分别为0.96kg、0.90kg,并与西杂二代差异显著(P<0.05);饲料消耗以皮西本较少,每kg增重消耗精、粗饲料分别为4.03kg和5.98kg。以皮西本和利西本2个杂交组合的屠宰成绩较好,18月龄屠宰率分别为61.50%、61.17%,净肉率分别为52.59%、49.21%。各组试验牛的高档肉块比例随着年龄的增长相应增加。 相似文献
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The multiple new challenges facing agriculture require the development of innovative cropping systems with high environmental, economic and social performances. Many research programmes are currently focusing on the design of such cropping systems. Some include the multicriteria assessment of cropping systems by diverse methods and approaches. Some of these research programmes are supported by experimental or farmers’ networks, generating new opportunities for data analysis and raising new research and methodological questions. In this article, we provide an overview based on a review of 56 articles, comparing the various methods for sustainability assessment in single- and multi-site studies. Articles were classified according to three characteristics: (i) their objectives, (ii) the study design (single- vs. multi-site), (iii) the type of system assessed (fictitious vs. real). Our analysis was structured around four items: (i) the variables used to describe cropping systems and production situations and the use of these variables in the assessment process, (ii) the criteria and associated indicators assessed, (iii) the methods used to explore multiple aspects of the performance of cropping systems, (iv) the use of reference values. We identified key points to be taken into account in multi-site studies. The application of the proposed guidelines to experimental networks should facilitate the identification of high-performance cropping systems and the identification of the drivers of cropping system performance. 相似文献
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2012年以来水产类上市公司经营面临困局.该研究根据11家水产类上市公司2012~2014年的面板数据,首先运用DEA模型进行生产效率的评价,研究发现水产类上市公司的技术效率、纯技术效率和规模效率3年平均值都较高,但2014年整体绩效有走低的趋势;然后运用Tobit模型,分析经营绩效的影响因素,发现公司总资产周转率和高等教育人员比例与技术效率正相关,而研发人员比例与技术效率不相关.最后,从资产整合、加强营销、重视人才和发展休闲渔业等方面提出了提高水产类上市公司经营绩效的对策建议. 相似文献
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