首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   13篇
  免费   4篇
农学   3篇
水产渔业   6篇
畜牧兽医   7篇
植物保护   1篇
  2020年   2篇
  2019年   3篇
  2017年   3篇
  2016年   2篇
  2015年   1篇
  2014年   4篇
  2012年   1篇
  2010年   1篇
排序方式: 共有17条查询结果,搜索用时 15 毫秒
1.
Anaesthetic substances are necessary to reduce fish stress during aquaculture activities. The objectives of this study were: (i) to determine the efficacy of essential oils (EOs) of Myrcia sylvatica (EOMS) and Curcuma longa (EOCL) as anaesthetics for Colossoma macropomum and (ii) to evaluate the effects of rapid anaesthesia and long‐term sedation (6 h) with these oils. Therefore, the main primary stress indicator (cortisol) and secondary factors (biochemical indices, hepatic metabolism, oxidative biomarkers) were measured. Sedation with the EOCL resulted in lower cortisol levels compared to control group. Total cholesterol levels were lower in fish sedated with EOMS than in control. Lactate levels were higher in fish anaesthetized with both EOs and sedated with EOCL compared to control. Both EOs increased hepatic glycogen levels after anaesthesia and EOMS increased this parameter after sedation compared to control. Anaesthesia and sedation with EOs resulted in lower levels of lipid peroxidation (LPO) compared to control. In turn, the activity of some antioxidant enzymes evaluated (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione‐S‐transferase), the content of non‐protein thiols and total reactive antioxidant potential were higher in tissues of fish anaesthetized and sedated with EOs compared to control. This induction of antioxidant capacity in the tissues could be due to the antioxidant property exerted by these EOs. Thus, EOMS and EOCL are recommended for anaesthesia and sedation of fish because in spite of inducing anaerobic metabolism, these EOs did not alter most biochemical parameters, reduced the LPO and increased the antioxidant capacity in vital tissues.  相似文献   
2.
Responses to anaesthesia with essential oil (EO) of Aloysia triphylla (135 and 180 mg L?1) and tricaine methanesulfonate (MS222) (150 and 300 mg L?1) were assessed in silver catfish. Exposure to the anaesthetics elicited a stress response in the species. In the case of MS222, it was displayed as a release of cortisol into bloodstream, elevation in hematocrit and plasma ion loss. The EO presented cortisol‐blocking properties, but increased haematocrit and disturbances of hydromineral balance were observed. Liver antioxidant/oxidant status of EO and MS222‐anaesthetized silver catfish was also estimated. The synthetic anaesthetic induced lipoperoxidation, notwithstanding increased catalase contents, whereas the naturally occurring product was capable of preventing the formation of lipid peroxides, possibly due to combined actions of catalase and glutathione‐S‐transferase. Anaesthetic efficacy was also tested via induction and recovery times. Overall, the promising results obtained for the physiological parameters of the EO‐treated fish counterbalanced the slight prolonged induction time observed for 180 mg L?1. As for 135 mg L?1, both induction and recovery times were lengthy; despite that, the EO was able to promote oxidative protection and mitigate stress. None of the MS222 concentrations prompted such responses concomitantly.  相似文献   
3.
In this study, we investigated the ability of matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) to characterize the lipid contents of canine spermatozoa. For that, samples of pure semen were analysed. Indeed, quite comprehensive lipid coverage was observed, and the most abundant phospholipid ions detected were from four phosphatidylcholines, that is those of m/z 760.6; 782.6; 808.6; and 830.6 and one of m/z 725.6 from a sphingomyelin. In conclusion, MALDI‐MS was found to offer an easy, fast, accurate, and sensitive analytical method for lipid profiling in canine spermatozoa and could be used as a tool to select sires by assessing the relationship between sperm lipid profiles and variables such as age and breeding history as well as to study the effects of cryopreservation on lipid contents.  相似文献   
4.
5.
化学杀雄是油菜杂种优势利用的一条重要途径,本试验选用3种化学杀雄剂(苯磺隆、WP 1和WP 2)并设置不同的浓度,对4个甘蓝型油菜常规品种(杨4、中11、早熟1号和早熟2号)和1个质不育系(中11 A)进行杀雄效果研究,获得了各供试油菜品种适宜的化学杀雄剂类型及施用浓度,为分别利用这4个油菜品种和质不育系中11 A作亲本进行杂交制种生产提供了一定的技术基础,对化杀油菜品种的种子生产有一定的实际指导作用。  相似文献   
6.
The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona‐free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre‐treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona‐free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo‐ vs in vitro‐matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona‐free and zona‐intact goat cloned embryos.  相似文献   
7.
The aim of this study was to evaluate the activity of eugenol against the fish pathogen Aeromonas hydrophila and eugenol's effect on hematological and natural immune parameters in silver catfish (Rhamdia quelen). In vitro, eugenol showed weak activity against A. hydrophila, but in vivo, at a subinhibitory concentration (10 mg L?1), it promoted survival in infected silver catfish. Eugenol (50 μg mL?1) reduced the hemolytic activity of A. hydrophila supernatant in vitro in fish erythrocytes. Subjecting catfish to eugenol baths (5 and 10 mg L?1) for five days did not alter the hematological and immunological parameters studied in this work. Based on these results, eugenol can be used to treat or prevent bacterial diseases in fish.  相似文献   
8.
Current therapy of Trypanosoma evansi infections is not effective for the vast majority of animals with relapsing parasitemia and clinical signs. Recently, attention is being focused on the antiparasitic activity of propolis. This study evaluated the susceptibility of T. evansi to propolis extract in vitro and in vivo. A dose-dependent trypanocidal activity of propolis extract was observed in vitro. All trypomastigotes were killed 1h after incubation with 10μgmL(-1) of the extract. In vivo, the concentrations of 100, 200, 300 and 400mgkg(-1) administered orally for 10 consecutive days showed no curative effect, and the rats died from the disease. However, rats treated with the two highest concentrations of propolis extract showed higher longevity than the other groups. Based on these data, we concluded that T. evansi is susceptible to propolis in vitro. Despite the lack of curative efficacy observed in vivo at the concentrations tested, the propolis extract can prolong life in rats infected with the protozoan.  相似文献   
9.
黔恢35是贵州省水稻研究所采用当地强恢复系R 785和重穗型恢复系R 894杂交选育而成的重穗型水稻新恢复系,具有穗粒数多、千粒重高、恢复力强、配合力高、植株壮实、花粉量大、花粉活力强、制种产量高等特性;利用自育抗稻瘟病不育系黔79 A与重穗型黔恢35所配组合黔优35经过2年区试及生产试验,于2018年4月通过贵州省农作物品种审定委员会审定。  相似文献   
10.
糯玉米新品种筑糯11号制种及亲本繁育技术   总被引:1,自引:0,他引:1  
陈甫玖  谭萍  黄朝兵  李承涛  傅同良 《种子》2019,(5):145-146,152
杂交糯玉米新品种筑糯11号系贵阳市农业试验中心用自育自交系遵三糯31作母本与自育系筑糯A 1作父本组配选育而成。该品种棒子大、苞叶好、产量高、品质好、适应性广等优点,具有广阔的市场开发利用前景。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号