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81.
Microorganisms associated with the vagina, cervix and uterus of rabbits were isolated and identified. The predominant microorganisms isolated from the vaginas and cervices were coagulase-negative staphylococci, micrococci, and nonfermentative bacilli. Coagulase-negative staphylococci were isolated frequently, but in small numbers, from the uteri. The pH of the rabbit vagina was found to be near neutrality. Our data indicate that the genital flora of female rabbits is relatively simple, regarding the number and type of microorganisms.  相似文献   
82.
The effect of inhibiting the rise in cortisol concentrations that occurs at copulation upon luteinizing hormone release was studied in seven adult boars. Plasma samples were collected for assay of luteinizing hormone, testosterone and cortisol on a control day and before, during and after exposure to an estrous sow. The area under the curve was used to evaluate hormone production and treatment effects were evaluated by a paired Student's t-test. The 11 beta-hydroxylase inhibitor, metyrapone, was used to suppress glucocorticoid hormone production. Cortisol concentrations increased significantly (p less than 0.05) after breeding compared to values on the control day while treatment with metyrapone prior to breeding prevented the cortisol increase (p greater than 0.05). Although luteinizing hormone production increased significantly after copulation in both breeding experiments, metyrapone pretreatment resulted in a reduction of luteinizing hormone secretion (p less than 0.05). Testosterone production was also reduced in boars pretreated with metyrapone. The results suggest that the increased levels of cortisol occurring at copulation may enhance luteinizing hormone release in boars.  相似文献   
83.
瘦素调控动物生殖活动的研究进展   总被引:4,自引:0,他引:4  
瘦素是白色脂肪细胞分泌的一种分子量为16kDa的分泌型蛋白激素,具有调控动物机体能量代谢平衡和体重的生物学作用。此外,作为机体的能量代谢信号,瘦素对动物初情期的启动和正常发情周期的维持 、生殖器官和生殖腺的发育等生殖活动和生殖机能均起着非常重要的调节作用。由于它的受体存在于多种生殖器官上,瘦素可在生殖轴的不同水平对生殖活动予以调节。瘦素在正丘脑水平对于生殖活动的调节可能是其直接作用于GnRH神经元  相似文献   
84.
周期性去叶对地毯草克隆生长的影响   总被引:1,自引:0,他引:1  
以地毯草为研究对象,通过随机区组试验,初步研究不同去叶周期对地毯草克隆生长的影响。结果表明,不同的去叶周期之间存在显著或极显著性差异,中等强度去叶(D20)最适宜地毯草的生长。而过度去叶(D10)或长时间未去叶(D60)都抑制了地毯草的正常生长,从而导致地毯草草坪使用价值下降。因此,中度去叶有利于地毯草的克隆生长,提高成坪速率及其观赏价值。  相似文献   
85.
根据对四川省畜禽龙头企业、合作社及养殖户的实地调研,发现不同的产品特点和产业发展阶段形成不同利益联结机制,这些机制具有不同的约束和激励效果,企业和农户的风险分担和利益分配关系也不同,并决定企业对原料产品质量安全水平的不同控制力。  相似文献   
86.
奶牛乳腺炎是由多种因素引起的严重影响奶牛业发展的重要疾病,初产牛临床和亚临床乳腺炎的流行和发病率,尤其在泌乳初期,均高于经产母牛.初产牛与经产牛的流行病学和危险因素不尽相同,为更加有效地控制初产牛乳腺炎,必须对初产牛乳腺炎进行深入系统的研究.论文重点论述了初产牛产前和产后临床、亚临床乳腺炎患病率和发病率,乳腺炎的致病因素,病原和诊断技术,介绍了国内外初产牛乳腺炎兽医防治、抗病育种等方面的研究成果.  相似文献   
87.
Teaching morphology, a fundamental part of medicine curricula is traditionally based on lectures and practical trainings. We introduced peer-assisted learning (PAL) and student expert teams to the courses to give the students the possibility to improve their free speech and self-confidence. We involved students in active preparation of online materials such as labelled e-slides and e-pics . We offered online digital microscopy (ZoomifyTM) and dissection (CyberPrep) allowing repeating the learned material and studying veterinary morphology outside the dissection theatre. Over 60% of first and third semester students profited from being a peer or being taught by a peer and 50% said the expert teams were an excellent method to learn the topographic anatomy. Almost all students applied ZoomifyTM and CyberPrep and 75% of them found the digital microscopy and dissection to be a helpful or very helpful learning tool. In face of reduced contact hours, these forms of education compensated in part the lost teaching time. We observed improvement of rhetoric and presentation skills and self-confidence. The approaches should therefore find their constant place in the veterinary medicine curricula.  相似文献   
88.
To explore the potential of a novel animal interferon formulation for controlled release, the yak interferon-alpha (IFN-α) glutathione S-transferase (GST) fusion protein was expressed in Escherichia coli (E. coli) and the purified recombinant IFN-α was encapsulated into solid lipid nanoparticles (SLN) by double emulsion solvent evaporation (w/o/w) method. The particle size and zeta potential of IFN-α-loaded SLN were 124.2 ± 10.2 nm and −11.2 ± 0.6 mV. The encapsulation efficiency of IFN-α and loading capacity of the SLN were 83.7 ± 4.5% and 1.73 ± 0.15%, respectively. In vitro release study and antiviral assay demonstrated that the IFN-α released from the SLN in a 16-day period exhibited antiviral activity in Madin-Darby bovine kidney (MDBK) cells against vesicular stomatitis virus (VSV), and showed a release pattern of an initial burst release followed by a sustained and slow release. Cytotoxicity assay in cell culture demonstrated that the SLN were not toxic. The results of this exploratory study suggest that the IFN-α-loaded SLN could be a useful formulation for controlled release in veterinary therapeutics.  相似文献   
89.
乳腺肿瘤是母犬最为常见的一类疾病,老龄母犬多见,公犬少见。美国的一项调查发现,乳腺肿瘤占犬类所有肿瘤的13.4%,而这些肿瘤有41.7名发生于未节育的母犬。据统计,纯种犬发病率高于杂种犬。肿瘤中恶性肿瘤约占40%。  相似文献   
90.
2010年以来,云南红河州个旧市一些不法分子大肆对锡矿石进行盗抢,给国家造成重大经济损失。为此,个旧市委、市政府决定对矿山进行一次专项整治,制止大规模集体盗抢违法行为的发生,个旧市公安局于3月12日抽调了4头警犬进驻治安较为复杂的1800矿区参与治安专项整治,掀开了矿山整治的序幕。目前,1800矿区的盗抢案件大幅度下降,警犬在专项整治中发挥了重要作用,收到了良好成效。  相似文献   
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