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101.
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新疆南部棉区黄萎病菌种群致病性分化及变异 总被引:3,自引:0,他引:3
采用鉴别寄主法和特异性引物PCR检测技术对采自新疆南部(南疆)棉区的36个棉花黄萎病菌菌系进行检测,以期明确其病原种群致病性分化及变异情况。鉴别寄主法测定结果显示:供试菌系中致病性强、中、弱的菌系分别为27个、4个和5个,各占75.0%,11.1%和13.9%。特异性引物(ND1/ND2和D1/D2)PCR检测结果显示,供试36个菌系中落叶型菌系12个,占33.3%;非落叶型菌系24个,占66.7%。经统计,落叶型菌系的致病力明显高于非落叶型菌系,其平均病指分别为43.8和31.8。接种试验证明,无论落叶型菌系和非落叶型菌系,接种后都可产生落叶症状,但落叶的情况有明显差别,落叶症状的轻重不仅与菌系的致病类型有关,还与棉花品种的抗病性密切相关。 相似文献
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Jensen TB Toft N Bonde MK Kongsted AG Kristensen AR Sørensen JT 《Preventive veterinary medicine》2012,103(1):31-37
Mortality of sows is a major problem for pig production worldwide. In this study, we used hierarchical multivariable logistic analyses to investigate different risk factors for mortality at the sow and herd level in herds with group-housed pregnant sows. Data included 3652 pregnant and 1266 lactating sows from 34 sow herds. A clinical examination for 16 clinical signs was carried out for each sow, and information about 16 herd related factors was obtained by interviews. Farm records were used to obtain information about whether or not sows died suddenly or were euthanized within 3 months after the clinical examination. Factors increasing the risk of sow mortality in the gestation unit were solid pen floors (OR = 1.87), presence of vulva bites (OR = 1.73) and unwillingness to stand when approached (OR = 1.62). Factors increasing the risk of sow mortality in the lactation unit were pale vulva color (OR = 12.69), body leanness (OR = 4.11), and presence of shoulder ulcers (OR = 2.89). The estimated between herd variation was small. Thus, the findings for the sow level variables may be generally applicable for sows in herds with group housed systems. 相似文献
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Lewis DH Chan DL Pinheiro D Armitage-Chan E Garden OA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2012,26(3):457-482
Sepsis, the systemic inflammatory response to infection, represents the major cause of death in critically ill veterinary patients. Whereas important advances in our understanding of the pathophysiology of this syndrome have been made, much remains to be elucidated. There is general agreement on the key interaction between pathogen-associated molecular patterns and cells of the innate immune system, and the amplification of the host response generated by pro-inflammatory cytokines. More recently, the concept of immunoparalysis in sepsis has also been advanced, together with an increasing recognition of the interplay between regulatory T cells and the innate immune response. However, the heterogeneous nature of this syndrome and the difficulty of modeling it in vitro or in vivo has both frustrated the advancement of new therapies and emphasized the continuing importance of patient-based clinical research in this area of human and veterinary medicine. 相似文献
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Hematologic and plasma chemistry RIs for cultured Striped catfish (Pangasius hypophthalmus) in recirculating aquaculture systems 下载免费PDF全文
109.
为了解潮霉素B预混剂临床驱除绦虫线虫的有效性和给药时间的合理性,依据兽药临床试验规范,试验选择了蠕虫自然感染皖西麻黄鸡824只,按要求随机分为3组,分别为潮霉素B预混剂治疗组284只,芬苯哒唑粉对照药物组284只,不治疗的感染对照组256只,试验周期根据临床治疗效果确定。结果显示,潮霉素B预混剂,推荐剂量10 mg/kg混饲,连续饲喂21 d,对鸡蛔虫和绦虫的粗计驱虫率分别为63%和26%,表现明显的驱除蛔虫作用(P0.05),连续饲喂42 d,对鸡蛔虫和绦虫的粗计驱虫率分别为100%和-13%,驱蛔虫效果极显著(P0.01);对照药物芬苯哒唑粉,50 mg/kg混饲,连续饲喂6 d,对鸡蛔虫和绦虫的粗计驱虫率分别为100%和44%,同样具有极显著的驱除蛔虫作用(P0.01),本试验中2种药物的驱蛔虫效果相当,对绦虫的驱除作用不明显(P0.05)。潮霉素B预混剂10 mg/kg混饲,连续饲喂42 d,可以驱净鸡蛔虫的感染,但对鸡绦虫感染无明显的驱除作用。 相似文献
110.
《Veterinary Clinics of North America: Exotic Animal Practice》2017,20(3):997-1010
Abstracts should be clear, transparent, and sufficiently detailed to convey the main elements of the study, including the question, primary outcome measure, study design, and main conclusions.6 Abstracts may influence whether busy clinicians will read the full article, and, if a study is not open access, practitioners may need to make clinical decisions from abstracts only. Consider also that, with new technologies and means of accessing information, the abstract content alone may serve as the 相似文献