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221.
There are indications in the literature that delaying the period between ovarian superestimulation and ovum pick up (OPU) would induce follicles to a condition of initial atresia, which could be beneficial to oocyte development. In this work, we compared three protocols for OPU and in vitro production (IVP) of embryos, in Nellore cattle. Nellore cows (n = 18) were randomly allocated in three groups: Group 1 (OPU), Group 2 [Follicle stimulating hormone (FSH) and OPU] and Group 3 (FSH deprivation and OPU). Three OPUs were performed, and the animals were switched to a different group each time (crossover), in such a way that at the end of the experiment all cows received the 3 protocols. At random stage of the oestrous cycle (D‐2), all follicles ≥ 6 mm were aspirated to induce a new follicular wave 2 days afterwards (D0). In Group 1, OPU was performed on D2 and oocytes were processed to IVP. In Group 2, starting on D0, cows were superstimulated (FSH, Folltropin®, 30 mg administered daily, i.m., during three consecutive days, total dose = 180 mg), and 6 h after the last FSH dose, they received exogenous luteinizing hormone (LH) (12.5 mg, i.m., Lutropin®, D3). The OPU was performed 6 h after LH administration, i.e. 12 h after the last dose of FSH. Animals in Group 3 received the same treatment as those in Group 2, except that LH was administered 42 h after the last dose of FSH, and OPU occurred 6 h later. Therefore, in this group, follicles were deprived of FSH at 48 h. Both cleavage and blastocyst rates were similar (p > 0.05, anova ) among oocytes from Groups 1, 2 and 3, respectively: 77.4% (144/185) and 42.70% (79/185); 75.54% (105/139) and 31.65% (44/139); 63.52% (101/159) and 33.33% (53/159). However, hatched blastocyst rate was higher (p < 0.01) in Group 1 (30.27%, 56/185) when compared with Group 2 (11.51%, 16/139) or 3 (15.72%, 25/159). It is concluded that, contrary to previous work on European breeds (Bos taurus), ovarian superstimulation associated with deprivation of FSH and OPU (Group 3) did not increase IVP of Nellore embryos (Bos indicus). On the contrary, the highest hatched blastocyst rates were observed in oocytes from non‐superstimulated cows.  相似文献   
222.
以温室黄瓜穴盘苗为对象,研究了不同营养液浓度(1倍、1/2倍、1/4倍和0倍)下不同生物菌肥[丰田宝(FTB)、地福来(DFL)、植动力(ZDL)、自制菌肥(ZZ)]的促根壮秧及化肥减施效果.结果表明:与不施肥和单施生物菌肥相比,生物菌肥与营养液混施均提高了黄瓜幼苗的株高、茎粗、叶片数及壮苗指数,其中100%营养液+Z...  相似文献   
223.
分析了我国烟草生产不同发展阶段的传统烟草种植和现代烟草种植模式下烟农种植过程中的成本投入,结果表明:因烟草专业化服务组织农业机械化水平和专业化程度的提高,烟草种植的人工投入数、人工成本分别由传统烟草种植模式的15.01个/667 m2和758元/667 m2降低到现代烟草种植模式的2.41个/667 m2和120.25元/667 m2;由于人工成本的大幅度降低,烟草种植总成本由传统烟草种植模式的798元/667 m2降低到现代烟草种植模式下的307.25元/667 m2。  相似文献   
224.
那曲东部土壤水分MODIS遥感反演研究   总被引:3,自引:0,他引:3  
陈涛  卓嘎  拉巴 《土壤通报》2017,(2):298-303
利用那曲东部2014年8月至2015年7月土壤水分观测资料与同期MODIS数据建立了研究区土壤水分遥感监测模型。表观热惯量法(ATI)反演土壤水分结果不理想,基于MODIS 8天合成数据以及晴空数据拟合结果的决定系数分别为0.4503和0.3753,晴空条件下ATI方法监测效果较差。基于单窗方法建立的四种模型中,三次多项式模型拟合效果较好,决定系数为0.5475,分析认为排除冬季数据后建模效果更好。结论:基于单窗方法的三次多项式模型能较好的反演研究区土壤水分,不足之处为对天气要求较高,若无晴空遥感数据,将影响土壤水分监测工作的开展。  相似文献   
225.
通过分析互助森林病虫害发生发展状况,根据在病虫害防治过程发现存在的问题,提出今后本区森林病虫害综合防治措施建议。  相似文献   
226.
Repair of hernias of the abdominal wall of horses is often augmented by inserting a prosthetic mesh. In this review, we describe the various characteristics of prosthetic meshes used for hernia repair and present 2 systems that are used by surgeons in the human medical field to classify techniques of prosthetic mesh herniorrhaphy. Both of these classification systems distinguish between onlay, inlay, sublay, and underlay placements of mesh, based on the location within the abdominal wall in which the prosthetic mesh is inserted. We separate the published techniques of prosthetic mesh herniorrhaphy of horses using this classification system, ascribing names to the techniques of herniorrhaphy where none existed, and report the success rates and complications associated with each technique. By introducing a classification system widely used in the human medical field and illustrating each technique in a figure, we hope to clarify inconsistent nomenclature associated with prosthetic mesh herniorrhaphy performed by veterinary surgeons.  相似文献   
227.
The Atmosphere Structure Instrument on the Galileo probe detected wavelike temperature fluctuations superimposed on a 700-kelvin temperature increase in Jupiter's thermosphere. These fluctuations are consistent with gravity waves that are viscously damped in the thermosphere. Moreover, heating by these waves can explain the temperature increase measured by the probe. This heating mechanism should be applicable to the thermospheres of the other giant planets and may help solve the long-standing question of the source of their high thermospheric temperatures.  相似文献   
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