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21.
22.
The potential contribution of separation technologies to the management of livestock manure 总被引:1,自引:0,他引:1
Separation processes have a distinct role in the management of livestock slurries, but it is important to recognise their limitations. Such technology can direct certain manure components into a small volume of a concentrated stream which is useful for the production of organic products in subsequent processes. Equipment generally falls into systems based either on mechanical screening (which can produce a fibrous and seemingly dry product), filtration processes (producing a cake), or sedimentation leading to a sludge product. Although physical separation can remove up to 80% of the total solids content from livestock manures, this will only include a relatively small part of the soluble nutrient and of the reactive organic matter; this is particularly so where separation is based on screens. The complete removal of all suspended matter (total clarification) of an effluent is theoretically possible by settling — a decanter centrifuge will accelerate the process. This can remove most of the phosphorous, especially if coupled with chemical pre-treatment to raise the pH. However, the clarified stream still retains a significant polluting potential in terms of the residual nitrogen content (as ammonia) and potassium. Only membrane separation can greatly reduce the potassium concentration, but such technology is rarely suitable for the farm situation. 相似文献
23.
蜂蟹螨(Varroa destructor)对福化利抗药性及其防治的研究 总被引:1,自引:0,他引:1
建立培养皿药膜法进行蜂蟹螨福化利(Fluvalinate)抗药浓度检测方法。分别以福化利浓度为0、12.5、25、50、100mg/L进行台湾5处蜂场蜂蟹螨抗福化利剂量调查,经回归分析,计算LC50之浓度介于23.75~79.25mg/L之间,比意大利抗性螨385~857mg/L仍低很多,显示抗药性尚未大幅增加。以隔落螨法防治蜂蟹螨平均每日可捕捉44.7~49.1只。比较隔落螨法、割雄蜂蛹加隔落螨法、蚁酸加隔落螨法、福化利防治法的效果,当蜂蟹螨密度不高时,可采用隔落螨法或加割雄蜂蛹方式进行防治,蜂蟹螨密度高时,可先以福化利、蚁酸进行1~2次防治,再配合隔落螨法,将可达到长期防治效果。 相似文献
24.
对青蒿素及其衍生物的作用机理及近年来其在防治鸡球虫病的应用做了较详细的综述,以期为其在防治鸡球虫病中的应用提供参考。青蒿素被用于治疗疟疾已有几百年的历史,它还具有治疗血吸虫、腹泻及清热、镇静安神的作用,但其在兽医临床中的应用还是一个新领域。 相似文献
25.
G. Basini S. Bussolati S. E. Santini F. Grasselli 《Journal of animal physiology and animal nutrition》2010,94(6):e374-e382
Soya and soybean products used in swine feeding contain genistein, a non‐steroidal phyto‐oestrogen which has been demonstrated to influence endocrine functions. This observation leads us to design this study to evaluate the effect of genistein on swine granulosa cell steroidogenesis and proliferation. In the attempt to unravel the genistein signal transduction mechanisms, we verified the effect of lavendustin, a Tyrosine Kinase (TK) inhibitor, and the potential involvement of NO/cGMP pathway. Finally, as angiogenesis is essential for follicle development, we tested the effect of the phyto‐oestrogen on vascular endothelial growth factor production and on granulosa cell redox status, because free‐radical species modulate neovascularization. Our data provide evidence that genistein interferes with granulosa cell steroidogenesis while it does not modulate cell growth: this effect could be at least partially produced by inhibiting TK‐dependent signalling systems. On the contrary, NO/cGMP pathway or vascular endothelial growth factor production can be excluded as signalling mechanism involved in phyto‐oestrogen effects. Remarkably, genistein stimulates hydrogen peroxide production thus potentially inhibiting follicular angiogenesis. Collectively, these results suggest that genistein consumption could potentially negatively impact swine reproductive function. 相似文献
26.
S.R. Porter C. Saegerman G. Van Galen C. Sandersen C. Delguste H. Guyot H. Amory 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(6):1411-1416
Background: Endocarditis is a rare heart condition with variable clinical expressions in equids. Risk factors for this disease are incompletely understood. Objective: Describe risk factors for endocarditis in equids. Animals: One hundred and fifty‐three equids admitted to Liège University, 9 diagnosed with endocarditis and 144 free from endocarditis but admitted to the hospital with a differential diagnosis including this disease. Methods: Retrospective case‐control study. Results: Equids with endocarditis were significantly younger (mean age = 4.84 ± 5.74 years) than control equids (mean age = 10.8 ± 7.73 years) (P= .01). No sex or breed predisposition was observed. Animals with hyperthermia (odds ratio [OR] = 24.4; confidence interval [CI] = 1.40–428), synovial distension (OR = 13.4; CI = 3.00–59.8), lameness (OR = 6.52; CI = 1.63–26.1), hyperglobulinemia (OR = 26.4; CI = 3.03–229), hypoalbuminemia (OR = 11.4; CI = 1.34–96.8), hyperfibrinogenemia (OR = 9.81; CI = 1.16–82.7), or leukocytosis (OR = 7.12; CI = 1.40–36.4) presented a significantly higher risk of having endocarditis than control horses. The presence of two of the clinical signs mentioned above significantly increased the probability of a diagnosis of endocarditis (P≤ .05). Conclusions and Clinical Importance: Age is associated with equine endocarditis. The diagnostic value of certain clinical signs and abnormalities in blood parameters in this disease are described. 相似文献
27.
Statistical control charts were used to detect process change in pig production. Two charts were tested to detect small deviations in production processes: the cumulative sum (CUSUM) control chart and the exponentially weighted moving average (EWMA) control chart. A Monte-Carlo simulation was used for developing an optimal design of the EWMA and the CUSUM charts. The traits piglets born in total and the return to oestrus rate were considered. Over a given time period, small shifts were purposely implemented to test the performance of the charts. The average time to signal (ATS) and false positive rate (FPR) were taken as classification parameters to evaluate the performance of the charts. All shifts in the number of piglets born in total were detected with CUSUM and EWMA control charts. The trait piglets born in total showed an ATS ranging from 1.3 (FPR = 33.5%) to 6.8 weeks (FPR = 1.2%) using the CUSUM chart. The EWMA chart presented an ATS which ranged between 2.0 (FPR = 14.9%) and 6.3 (FPR = 1.9%) weeks. The application of the CUSUM to the return to oestrus rate resulted in an ATS of 2.6 (FPR = 38.3%) to 15.6 weeks (FPR = 3.0%) and the EWMA chart produced a signal between 4.1 (FPR = 14.5%) and 16.4 weeks (FPR = 1.4%). Both charts appear to be useful tools for tracking commercial swine farm processes and detecting emerging change in process performance. 相似文献
28.
西藏“一江两河”流域中部草地沙漠化与防治 总被引:3,自引:0,他引:3
据1:3.5×10^4假彩色红外航空像片室内判读与野外调查,本区沙漠化草地可分为中度及轻度两种,面积12.823万hm^2,导致草地沙漠化的人为因素主要是超载过牧,樵柴,放牧制度不合理等,草地沙漠化防治可采取生物,管理及工程等措施。 相似文献
29.
30.
贵州足球场草坪主要病虫害发生及防治 总被引:4,自引:0,他引:4
1998~ 1999年对贵州省足球场草坪病虫害进行了调查研究 ,其主要病虫害有 :锈病、禾草云斑病、褐斑病、禾生腐霉病、粘虫 ,麦二叉蚜等。并阐述了病虫害发生规律及防治技术 ,旨在为足球场草坪病虫害的防治提供参考 相似文献