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导读:人类面临可能发生的流感大流行威胁主要来自H5N1病毒引起的高致病性禽流感.但H5N1,病毒要引起人间的大流行,必须经过禽间大流行、禽类传染给人类、人间大流行几个阶段.正如WHO提出的关于判断一种传染病大流行是否能够来临的四项标准:一是人类对该病毒没有免疫力;二是该病毒很容易从动物的身上传到人的身上;三是该病毒对人有致命性;四是该病毒可以形成有效的人与人之间的传播. 相似文献
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呼吸道合胞病毒(Respiratory syncytial virus,RSV)是在世界范围内引起婴幼儿下呼吸道感染的重要病毒之一,首次感染多发生于1岁以内的婴儿,2月龄婴儿的发病率最高.感染该病毒后不能产生持久的免疫力,可以反复感染,是造成婴幼儿住院的主要原因,也是青少年、老年人以及免疫缺陷人群呼吸道感染的重要病原,因此世界卫生组织要求对其严加监控.呼吸道合胞病毒在我国不但有散发流行,而且还曾引起数次大规模的流行.在南方,呼吸道合胞病毒流行高峰主要在炎热的夏秋季,而北方则发生在寒冷的冬春季.用单克隆抗体对我国部分地区呼吸道合胞病毒分离株亚型监测的结果表明,目前我国流行的呼吸道合胞病毒主要为A亚型. 相似文献
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通过将6.5周龄的未曾接触过PRRSv的小母猪与年龄一致但接种了该病毒地方流行株的小母猪混合饲养、或将10.5周龄小母猪通过与接种或接触暴露过PRRS病毒地方流行株的小母猪混合饲养,以验证能否使PKKsv敏感型小母猪适应该病毒地方流行株. 相似文献
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羊病毒性口炎又叫羊口疮.该病毒对外界环境的抵抗力很强,散落于地面的病毒可以越冬,至来年春季仍有感染性,由于病毒的这一特点,它可以在羊群里面危害多年.本病以3至6月龄的羔羊发病居多,常呈群发性流行.成年羊也可感染发病,但呈散发性流行.该病毒主要通过损伤的皮肤、粘膜感染.引入的病羊或带毒羊是传染的来源. 相似文献
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牛流行热以前简称牛流行性感胃,是由流行热病毒引起急性、热性、高度接触性传染病.流行具有一定的周期性,一般每隔几年或3～4年发生1次较大规模的流行.发病以夏秋季较多发生,尤其是天气闷热多雨季或昼夜温差较大易引起流行.
1 病原学
牛流行热病毒为弹状病毒科暂时热病属成员,只有1个血清型.该病毒对外界的抵抗力不强,对热敏感,56℃10分钟,37℃18小时可灭活;pH值在2.5以下或pH值在9以上于10分钟内可以使之灭活,对一般消毒药物较敏感. 相似文献
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牛呼吸道合胞体病毒是引起牛呼吸道疾病综合征的主要病原之一.该病毒在世界各地广泛分布,牛群中的流行与感染率较高.本文主要介绍了牛呼吸道合胞体病毒的流行病学与诊断. 相似文献
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截止于2013年4月2日,国家卫生和计划生育委员会通报我国上海市、安徽省和江苏省共发现7例人感染H7N9禽流感病例,其中2例死亡.由于H7N9禽流感病毒感染人是世界范围首次出现的事件,该消息一经报出,立即引发了很大的反响,人们担忧此次出现的新型流感病毒是否会形成大流行.鉴于当前对该病毒的基因特性、生物学特性及传播能力尚不清晰,为了使读者更好的认识H7N9亚型禽流感病毒,本文回顾H7亚型流感病毒的特性、H7亚型禽流感病毒在家禽中的流行情况和对人类的感染情况,以及如何采取有效措施控制该病毒的流行. 相似文献
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猪口蹄疫的特点与防治 总被引：4，自引：1，他引：3
1 口蹄疫病毒特征 口蹄疫是由口蹄疫病毒(FMDV)感染引起的偶蹄动物共患的急性、热性、高度接触性传染病,最易感染的动物是牛、猪、骆驼、羊、鹿等,野猪、野牛等野生动物也易感染此病.本病以牛最易感,羊的感染率较低.口蹄疫在亚洲、非洲和中东以及南美均有流行,在非流行区也有散发病例.该病毒具有多型性、易变的特点.口蹄疫病毒有O、A、C、Asial、SAT1、SAT2、SAT3等7个血清型和60多个亚型. 相似文献
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试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。 相似文献
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Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections
of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal
(GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April
2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs
located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming
areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology
laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum
columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying
degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal
abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy
season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different
nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those
observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes.
But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the
results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia. 相似文献
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B. Cinar Kul N. Bilgen J.A. Lenstra O. Korkmaz Agaoglu B. Akyuz O. Ertugrul 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):449-453
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded. 相似文献
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Bazin H 《Comparative immunology, microbiology and infectious diseases》2003,26(5-6):293-308
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing. 相似文献
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The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies. 相似文献
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Troxel MT Vite CH Van Winkle TJ Newton AL Tiches D Dayrell-Hart B Kapatkin AS Shofer FS Steinberg SA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):850-859
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma. 相似文献
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Bovine Mastitis in Selected Areas of Southern Ethiopia 总被引：3，自引：0，他引：3
A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area. 相似文献
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不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响 总被引：2，自引：0，他引：2
本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。 相似文献
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Emma Scurrell Sue Manning Pedro Malho Alex Civello John Mould Rossella Carrozza Bart E. Wagner 《Veterinary ophthalmology》2020,23(2):402-408
A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed. 相似文献