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21.
22.
低成本省力化栽桑技术的研究进展 总被引:2,自引:0,他引:2
我国已育成了若干适合条桑育,适于扦插的桑品种及适于种子直播的杂交桑,为建立高密度低成本桑园打下了基础。推广了直接用袋接体,硬枝扦插和杂交种直接建园和初试了中晚秋条桑收获技术。今后的研究方向是选育发根性强,高产优势,适合条桑收获的桑树品种及以条桑收获为主的提高劳动生产率的栽培技术。 相似文献
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24.
Silvia Pietschmann Katrin Hoffmann Michael Voget Ulrich Pison 《Veterinary research communications》2009,33(6):489-505
The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological
profile of the drugs. To assess the value of an antibiotic combination of polymyxin B and miconazole this study examined the
in vitro synergistic potential of the two drugs on Gram-negative and Gram-positive bacteria and yeast. Antifungal and antibacterial
activity was tested by minimum inhibitory concentration (MIC) of broth macrodilution and urea broth microdilution, by fluorescence
microscopy and flow cytometry. Synergism was calculated using the fractional inhibitory concentration index (FICi). With Staphylococcus intermedius as target we found up to an eightfold reduction of the individual MICs when both drugs were combined. However, the FICi was
0.63 suggesting no real interaction between the two drugs. With Escherichia coli, Pseudomonas aeruginosa, and Malassezia pachydermatis as targets the antimicrobial drug combination reduced the MICs of polymyxin B and miconazole from fourfold to hundredfold
resulting in FICi between 0.06 and 0.5 which defines a synergistic action. Thus, if polymyxin B and miconazole are combined
their effect is greater than the sum of the effects observed with polymyxin B and miconazole independently, revealing bactericidal
and fungicidal synergism. Our results indicate a strong therapeutic value for the combination of these antimicrobial agents
against Gram-negative bacteria and yeast and a weaker value against Gram positive bacteria for clinical situations where these
pathogens are involved. 相似文献
25.
Awareness of animal influenza and its prevention and control is important for ensuring livestock health, production and welfare. In China, a country stereotyped as a major source of emerging zoonotic infectious diseases, research on the public understanding of animal influenza is limited to the Han, the main ethnic group. The present qualitative study in Southwest China investigated awareness of animal influenza among the Dai, an ethnic minority. The participants (15 men and 10 women, ages 18–83) were smallholder farmers of pigs and poultry in rural areas of Jinghong, Xishuangbanna, Yunnan Province. A mixture of interviews and group discussions took place in homes and villages. The participants were asked about their knowledge of avian influenza (H7N9), swine influenza (H1N1), precautions taken to protect against influenza, procedures when animals were sick and perceived risk of animal influenza. The data were analysed following coding and thematic analysis. The findings demonstrated a limited understanding of animal health and welfare among participants. Specifically, they were largely unaware of animal influenza (H7N9, H1N1) including its causes, symptoms, prevention and treatment. The farmers were also uninformed of the risks they faced and unknowingly engaged in behaviours which increased direct or indirect exposure to infected animals, a risk factor for human infection. They also reported poor usage of veterinary services. In order to guarantee the health, welfare and production of their livestock, immediate action is needed to enable Dai smallholder farmers to prevent and respond to animal influenza effectively and timely. 相似文献
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28.
乳体细胞数(SCC)在奶牛养殖业中的应用 总被引:2,自引:0,他引:2
乳中体细胞一直是众多研究者研究的焦点,体细胞数(SCC)是衡量奶牛乳房健康状况和乳品质量的一项重要指标(William[1]等,2001),Shook[2](1989)指出SCC是乳房炎的一种有效的标记性状. 相似文献
29.
Michael H. Woodford 《Tropical animal health and production》2009,41(7):1023-1033
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental
security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission
and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human
population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade
in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the
ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded
townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The
emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to
increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted
and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent
and its human, domestic and wild hosts is stressed. 相似文献
30.
Du YH Jia RY Yin ZQ Pu ZH Chen J Yang F Zhang YQ Lu Y 《Veterinary parasitology》2008,157(1-2):144-148
The acaricidal activity of the petroleum ether extract, the chloroform extract and the acetic ether extract of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae was tested in vitro. A complementary log-log (CLL) model was used to analyze the data of the toxicity tests. The results showed that at all test time points, the petroleum ether extract demonstrated the highest activity against the larvae of S. scabiei var. cuniculi, while the activities of the chloroform extract and the acetic ether extract were similar. The activities of both the petroleum ether extract and the chloroform extract against the larvae showed the relation of time and concentration dependent. The median lethal concentration (LC(50)) of the petroleum ether extract (1.3muL/mL) was about three times that of the chloroform extract (4.1muL/mL) at 24h post-treatment. At the concentrations of 500.0muL/mL, the median lethal time (LT(50)) of the petroleum ether extract and the chloroform extract was 8.4 and 9.6h, respectively. 相似文献