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1.
贵州农民财产性收入研究   总被引:1,自引:0,他引:1  
阐述了财产性收入对提高贵州农民收入的重要性,深入分析了贵州农民财产性收入存在的问题和现状,并试图探索提高贵州农民的财产性收入的途径。  相似文献   
2.
通过实验表明:在冬季最低气温-28.3℃的黑龙江省密山市饲养产蛋鸡,只要鸡舍保温良好,适当增加鸡的饲养密度,不用供热,也可保持鸡舍内温度在13℃—15℃的最佳鸡产蛋环境温度;在151天的冬季里实验组鸡,按入舍鸡计算平均每只鸡产蛋103.8个,产蛋率为68.74%,仅比对供热取暖鸡舍的对照组鸡群产蛋率低0.5%,故在寒冷的黑龙江省推广产蛋鸡舍冬季不供热是完全可能的,其经济效益也是显著的。  相似文献   
3.
Abstract. Nitrous oxide (N2O) is involved in both ozone destruction and global warming. In agricultural soils it is produced by nitrification and denitrification mainly after fertilization. Nitrification inhibitors have been proposed as one of the management tools for the reduction of the potential hazards of fertilizer-derived N2O. Addition of nitrification inhibitors to fertilizers maintains soil N in ammonium form, thereby gaseous N losses by nitrification and denitrification are less likely to occur and there is increased N utilization by the sward. We present a study aimed to evaluate the effectiveness of the nitrification inhibitor dicyandiamide (DCD) and of the slurry additive Actilith F2 on N2O emissions following application of calcium ammonium nitrate or cattle slurry to a mixed clover/ryegrass sward in the Basque Country. The results indicate that large differences in N2O emission occur depending on fertilizer type and the presence or absence of a nitrification inhibitor. There is considerable scope for immediate reduction of emissions by applying DCD with calcium ammonium nitrate or cattle slurry. DCD, applied at 25 kg ha–1, reduced the amount of N lost as N2O by 60% and 42% when applied with cattle slurry and calcium ammonium nitrate, respectively. Actilith F2 did not reduce N2O emissions and it produced a long lasting mineralization of previously immobilized added N.  相似文献   
4.
Bovine cumulus-oocyte complexes (COCs) were aspirated from antral follicles (3–6 mm in diameter). COCs with a compact multilayered cumulus investment were cultured for 9, 13 and 24 hours, respectively, and processed for scanning or transmission electron microscopy after different periods of culture including a 0 hour control group. In all 0 hour control COCs initial formation of cumulus cell projections, blebs and microvilli were observed. The start of cumulus-oocyte disconnection in cattle was observed after 9 hours of in vitro culture. These connections were almost completely discrupted after 13 hours, when a continuous production of extracellular matrix was observed. The full expansion of corona radiata cells was not observed even after 24 hours. Some cumulus oophorus cells were bound together with junctions of the zonula adherens type after 24 hours when extracellular matrix was found only in deeper layers. The full expansion of corona radiata cells was not the prerequisite for disconnection of cumulus-oocyte complex. Inhalt: Kumulus oophorus Expansion von in vitro kultivierten Rinderoozyten: Eine SEM und TEM Untersuchung Kumulus-Oozyten-Komplexe (COC) von Rindern wurden aus antralen Follikeln aspiriert (Durchmesser 3–6 mm). COC's mit kompakten mehrschichtigen Kumulus wurden für 9, 13 und 24 Stunden kultiviert und für die Scanner- oder Transmissionselektronenmikroskopie vorbereitet. Verschiedene Kulturzeiten incl. einer 0-Stundengruppe als Kontrolle wurden untersucht. In allen Kontroll COC's wurden beginnende Formationen yon Kumuluszellprojektionen, Bläschen und Mikrovilli beobachtet. Nach 9-stündiger in vitro Kultur begann die Lösung zwischen Kumulus und Oozyte. Die Verbindungen waren nach 13 Stunden vollständig unterbrochen, wobei eine kontinuierliche Produktion extrazellulärer Matrix beobachtet wurde. Eine vollständige Expansion der Corona radiata Zellen wurde auch nicht nach 24 Stunden beobachtet. Nach 24 Stunden waren einige Cumulus Oophorus Zellen über Verbindungen des Zonula adherens Typs verknüpft, wobei extrazelluläre Matrix nur in den tieferen Zellschichten gefunden wurde. Eine vollständige Kumulusexpansion ist keine Voraussetzung für die Auflösung des Kumulus-Oozyten-Komplexes.  相似文献   
5.
用本课题组研制的肉牛添加剂育肥体重230kg、330kg、400kg和530kg的肉牛,可使日增重分别提高25.5%、7.3%、25.4%和16.7%,效果显著(P<0.05),可使饲料报酬最多提高25.8%(P<0.05);投入产出比最大为1:8,用该添加剂育肥高档肉牛时屠宰率可达57.2%,眼肌面积43cm2、皮下脂肪覆盖面积为优级,大理石状评分为优级。  相似文献   
6.
利木赞牛改良互助本地黄牛的效果   总被引:1,自引:1,他引:0  
为了研究利木赞牛对互助黄牛的改良效果,本试验测定了初生、6月龄和1岁利本F1代的体尺、体重,并与本地黄牛进行了比较。结果表明,利本F1代牛的各项被检指标均比本地黄牛有明显的提高(P<0.01)。  相似文献   
7.
A questionnaire study examining Japanese consumers’ requirements for beef quality was carried out in April 2002 in Tsukuba, Ibaraki, Japan. Answers from 532 participants were used for the statistical analysis. Twenty questions about sensory properties, appearance, safety and freshness, production area, price, and other properties were prepared. The answers were applied to principal component analysis. Five principal components were obtained and defined, and the principle component scores were used to classify participants. The panels were classified into four groups profiled as ‘specific quality orientated’, ‘Wagyu (Japanese beef) orientated’, ‘safety and freshness orientated’ and ‘overall high quality orientated’. In addition, gender and age characteristics were different among the groups. Sensory properties did not affect the classification of respondents.  相似文献   
8.
9.
A nonblinded, positively controlled, noninferiority trial was conducted to evaluate the efficacy of an alternative, nonantibiotic therapy with Masti Veyxym® to reduce ineffective antibiotic usage in the treatment of nonsevere clinical mastitis (CM) in cows with longer lasting udder diseases. The solely intramammary treatment with Masti Veyxym® (three applications, 12 hr apart) and the combined treatment with Masti Veyxym® and antibiotics as usual on the farm according to label of the respective product were compared with the reference treatment of solely antibiotic therapy. The matched field study was conducted on eight free‐stall dairy farms located in Eastern Germany. Cases of mild‐to‐moderate CM in cows with longer lasting high somatic cell counts in preceding dairy herd improvement test days and with previous CM cases in current lactation were randomly allocated to one of the three treatment groups. A foremilk sample of the affected quarter was taken before treatment and again approximately 14 days and 21 days after the end of therapy for cyto‐bacteriological examination. Primary outcomes were clinical cure (CC) and no CM recurrence within 60 days after the end of treatment (no R60). Bacteriological cure (BC) and quarter somatic cell count (QSCC) cure were chosen as secondary outcomes although low probabilities of BC and QSCC cure for selected cows were expected. The study resulted in the following findings: the pathogens mostly cultured from pretreatment samples were Streptococcus uberis, followed by Staphylococcus aureus and coagulase‐negative staphylococci. There were no significant differences between the two test treatments in comparison with the reference treatment regarding all outcome variables. The sole therapy with Masti Veyxym® resulted in a numerically lower likelihood of BC without significant differences to the reference treatment. The combined therapy group showed a numerically higher nonrecurrence rate than the two other treatment groups and noninferiority compared to the reference treatment was proven. Having regard to the selection criteria of cows in this study, the findings indicated that sole treatment with Masti Veyxym® in nonsevere CM cases may constitute an alternative therapy to reduce antibiotics. However, noninferiority evaluations were mostly inconclusive. Further investigations with a larger sample size are required to confirm the results and to make a clear statement on noninferiority.  相似文献   
10.
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