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991.
付广建  王永卫  杨奇  王建华  张国坪 《安徽农业科学》2007,35(4):1044-1045,1105
2005年8月至2006年1月对宁南山区的肉牛养殖情况和营养代谢病的发病率进行了抽样调查, 并采集50份血样进行了血液常规检查和钙、磷、钠、钾、氯、硫、铜、硒、钼、锌、钴、锰、铁、氟共14种元素的分析.结果表明:血液常规检查基本正常,宁南山区肉牛处在铁、氟过量,钙、锰、钼充足,磷、钠、钾、氯、钴、硒缺乏,锌区域性缺乏的状况.  相似文献   
992.
A genuine biophysical method, Fourier transform-infrared (FT-IR) spectroscopy has become a versatile research tool in biochemistry and biomedicine. Topical applications in microbiology and prion research are impressive illustrations of the vigorous evolution of the technique. FT-IR spectroscopy has established itself as a powerful method for the rapid differentiation and identification of microorganisms, thereby contributing to both clinical medicine and the prevention of bioterrorism. It has also led to considerable progress in various other fields of basic research, not least in prion sciences. In this field, FT-IR spectroscopy has been increasingly applied as a tool for elucidating structural features of the pathological prion protein, and also to study the molecular changes induced by prions in neuronal tissue and blood. This article sets out to give a review of current examples of the analytical potential of FT-IR spectroscopy in microbiology and prion research.  相似文献   
993.
Previous studies have described a "litter effect" associated with mortality in postweaning multisystemic wasting syndrome (PMWS) affected farms. The main objective of this study was to evaluate litter mortality in different PMWS affected farms and to characterize it in relation to three variables of the sow: parity, porcine circovirus type 2 (PCV2) infectious status and PCV2 antibody titres. The study was performed in seven farms that experienced PMWS in nurseries and/or fattening areas. Fifteen sows from each farm were randomly selected from the same farrowing batch. Serum samples were analyzed for antibodies to PCV2 and for genomic detection of PCV2. Four piglets from each sow (60 piglets per farm) were selected and ear-tagged at birth. Out of 420 initial piglets, 104 (25%) died. Sixty three of them (60%) were necropsied, and 40 (63%) diagnosed as PMWS based on case definition criteria. Our results show that sow PCV2 viremia was significantly related to piglet mortality since more piglets per litter died from viremic than from non-viremic sows. Additionally, a significantly greater proportion of animals died from sows that had low antibody titres against PCV2 (39% vs. 18% from sows with medium to high antibody titres). The present study, of exploratory nature, confirms previous results and further characterizes the so called "litter effect" by establishing that the sow PCV2 status had a significant effect on litter mortality in PMWS affected farms.  相似文献   
994.
近年来, 随着计算机、互联网、物联网、人工智能、传感器、遥感等技术的快速发展, 智能虫情测报灯、智能性诱捕器、昆虫雷达、无人机遥感、卫星遥感、智能识别App等现代智能农作物病虫监测装备及重大病虫害实时智能监测预警系统建设方面取得了比较明显的进步。本文综述了我国近5年在利用光谱遥感、昆虫雷达、图像识别等技术进行农作物病虫害监测预警研究和应用方面取得的重要进展, 分析了各类技术存在的不足与难点, 提出了未来发展的方向, 以期为充分利用空天地多源数据实现农作物病虫害精准预报提供指导。  相似文献   
995.
近10年来, 随着人们对环境的关注, 绿色发展成为农业生产的主流。在土传病害的防治中, 要尽可能减少对环境和生态的影响, 同时保证取得更好的经济效益。因而, 一些环境友好的防治技术受到重视。农业防治技术如抗性品种利用和嫁接、阻截传播、深翻、轮作和无土栽培; 生物防治技术如生物熏蒸、厌氧消毒、生物防治制剂等; 物理防治技术如太阳能消毒、火焰消毒、微波消毒、电消毒、射频消毒也在不断地创新; 化学防治技术主要依赖土壤熏蒸剂, 一些新型的环境友好的熏蒸剂如异硫氰酸烯丙酯、二甲基二硫、乙二腈、乙蒜素等也在不断发展。熏蒸剂新剂型、新的施药机械也在不断创新。土壤熏蒸剂在防治土传病害时, 也会对土壤中的微生态造成不同程度的影响。此外, 我们也应该清醒地认识到任何技术都有两面性, 并正视不同防治技术中的不足。土传病害作为一类难以防治的病害, 也面临着巨大的挑战, 高传染性要求有高质量的种苗和高效的防治和阻隔技术, 土传病害的定量检测技术, 土壤中的病原菌数量与发病的关系、土壤微生态对发病的影响都是亟待研究和解决的问题。在防控土传病害时, 如何减少温室气体的排放、减少防治投入以及塑料薄膜的污染均为面临的环境和经济学挑战。  相似文献   
996.
本文回顾了郭予元院士在20世纪80-90年代对中国主要粮棉作物多病虫复合群体综合防治技术体系研究与实践中的重要工作, 包括组建粮棉作物多病虫复合群体综合防治技术体系的创新性思路、创建主要粮棉作物多病虫复合群体综合防治技术体系, 以及对21世纪我国粮棉作物多病虫复合群体综合防治技术体系提出的发展前景和目标等, 其中粮棉作物多病虫复合群体综合防治技术体系实施后取得了显著成效。郭予元院士在我国主要粮棉多病虫复合群体综合防治领域的相关学术思想及贡献, 对我国农作物病虫害综合防治、可持续治理、绿色防控策略制定以及植物保护学科的发展产生了深远的影响, 为我国实现农作物生物灾害可持续控制做出了重要贡献。  相似文献   
997.

Background

Canid herpesvirus-1 (CaHV-1) infection in puppies less than three weeks of age is often reported to be associated with a lethal generalized necrotizing inflammation and since the discovery of the virus in 1965 several reports of neonatal infections have been published. However, the significance of CaHV-1 for peri- and neonatal mortality in puppies remains unclear. Therefore, we examined stillborn and dead neonatal puppies in Denmark to determine the prevalence of infection and further to correlate infection levels with necropsy findings to assess the possible significance of the infection.

Results

From a cross-sectional study of 57 dead puppies, 22.8% (n = 13) were confirmed positive for CaHV-1 by real-time polymerase chain reaction (PCR) of tissue pools of lung/liver and/or spleen/kidney. Specimens from PCR positive cases were further investigated by histology and in situ hybridization (ISH). High levels of CaHV-1 DNA were present in only one case in which lesions and ISH staining consistent with CaHV-1 infection were found as well. CaHV-1 concentrations in the other cases were low and a range of lesions not consistent with CaHV-1 were found. Similar, ISH staining was mostly negative in these except for one case with a few positive cells.

Conclusion

CaHV-1 infection in stillborn and dead neonatal puppies in Denmark seems to be common, but the direct significance for puppy mortality remains unclear as only one of 13 PCR positive puppies (7.7%) had pathognomonic lesions.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-014-0092-9) contains supplementary material, which is available to authorized users.  相似文献   
998.
The role of chronic inflammation and autonomic neuropathy in the crucial underlying process contributing to the initiation and the progression of various cardiovascular diseases is well established. It is well known that the immune system is innervated by the autonomic nervous system, and the inflammatory reaction and immune reaction are re-gulated by the autonomic nerve system. Vagus nerve depresses inflammatory reaction via cholinergic anti-inflammatory pathway(CAP), while sympathetic nervous system has bidirectional regulation of pro-inflammation and anti-inflammation, which are affected by several factors such as the concentration of neurotransmitters or types of receptors. In this paper, we reviewed different effects of CAP and sympathetic nervous system on cardiovascular inflammatory reaction. Activation of CAP and regaining normal sympathetic function will improve the chronic inflammation in the process of cardiovascular diseases. Low-toxic and selective α7nAchR agonist is expected to be applied in cardiovascular diseases to alleviate chronic inflammation.  相似文献   
999.
International dog imports pose a risk because of the potential movement of disease agents, including the canine rabies virus variant which has been eliminated from the United States since 2007. US regulations require a rabies vaccination certificate for dogs arriving from rabies‐endemic countries, but permit the importation of dogs that have not been adequately immunized against rabies, provided that the dogs are confined under conditions that restrict their contact with humans and other animals until they have been immunized. CDC Form 75.37, ‘Notice to Owners and Importers of Dogs’, explains the confinement requirements and serves as a binding confinement agreement with the importer. In this evaluation, we describe the characteristics of unimmunized dogs imported into the United States over a 1‐year period based upon dog confinement agreements recorded at the Centers for Disease Control and Prevention (CDC) quarantine stations. Confinement agreements were issued for nearly 2800 unimmunized dogs that entered the United States during 1 June 2011–31 May 2012, the majority of which travelled to the United States by air and without any seasonal pattern in import volume. Over 60% of these animals were puppies <3 months of age and included a wide variety of breeds. The dogs arrived from 81 countries, with the majority arriving from North America or Europe. Dogs placed on confinement agreements had final destinations in 49 states. California, New York, Texas, Washington and Florida received the largest number of dogs on confinement agreements. These results (which do not reflect human travel or US dog ownership data) suggest that a large portion of unimmunized dogs arrive from rabies‐endemic countries for commercial, shelter and rescue purposes. Further evaluation and key stakeholder involvement are needed to assess whether the current dog importation regulations are an adequate compromise between the benefits and risks of dog importation.  相似文献   
1000.
Worldwide, foodborne illness is a significant public health issue in both developed and developing countries. Salmonellosis, campylobacteriosis and shigellosis are common foodborne gastrointestinal illnesses caused by the bacteria Salmonella spp., Campylobacter spp. and Shigella spp. respectively. These zoonotic diseases are frequently linked to eggs and poultry products. The aim of this study was to investigate the presence of these pathogens in Australian backyard poultry flocks and to determine risk factors for these pathogens. Poultry faeces samples were collected from 82 backyards and screened for Salmonella spp., Campylobacter spp. and Shigella spp. using qPCR. A questionnaire was administered to the backyard poultry owners to assess their knowledge regarding management of poultry and eggs and to identify potential risk factors that may contribute to the presence of zoonotic pathogens in the flocks. One composite faecal sample was collected from each backyard (82 samples). Composite sampling here means taking one or more grab samples from a backyard to make up approximately 10 grams. Four per cent of samples, that is 4% backyards tested, were positive for Salmonella spp., 10% were positive for Campylobacter spp. and none were positive for Shigella spp. A higher infection rate was seen in multi-aged flocks (24%) compared with the single-aged flocks (3%). The survey found that many participants were engaging in risky food safety behaviours with 46% of participants responding that they washed their eggs with running water or still water instead of wiping the dirt off with a damp cloth to clean the eggs and 19% stored their eggs at room temperature. This study demonstrated that backyard poultry may pose a potential risk for salmonellosis and campylobacteriosis. Additionally, Australian public health and food safety regulations should be modified and effectively implemented to address the risks associated with backyard poultry husbandry.  相似文献   
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