自主活动鸟类禽流感及新城疫的生态学与流行病学调查分析

在2004年初H5亚型禽流感在中国内地引起暴发前后，于湖北、广西二疫区市县的生态系中，自健康的鹰、鸽子、野鸭和鹌鹑中采集了54份血清，应用血凝抑制试验（HI）对其进行了血清学检测，并将获得的血清学检测数据进行了统计学分析。分析结果显示，在总共采集的54份血清样品中，抗新城疫病毒（NDV）抗体、抗It6亚型禽流感病毒（H6）抗体、抗H9亚型禽流感病毒（H9）抗体、抗H5亚型禽流感病毒（H5）抗体阳性率分别为64．8％、64．8％、75．9％、29．6％。推断这一时期新城疫病毒（NDV）、H6亚型禽流感病毒（H6）、H9亚型禽流感病毒（H9）和H5亚型禽流感病毒（H5）共循环于该生态系中，其中新城疫病毒、H9、H6亚型禽流感病毒长期、稳定循环于该生态系中，为该生态系主要流行血清型。血凝抑制试验检测结果发现，抗H5亚型禽流感病毒抗体效价较低，最高仅为640，其阳性率为29．6％，推断其可能为新近传入的病毒或新近重组变异出现的新病毒、与该次流感暴发相关的新病毒，这一推断还有待于通过对病毒基因序列的分析而做进一步验证：另外，新城疫病毒在该生态系中的稳定循环，构成了对家禽持久、潜在的威胁。对于自1994年以来，长期稳定循环于我国生态系及家禽中的H9亚型禽流感病毒则仍然是以G9-like为优势亚组。本研究结果还提示我们，对我国自主活动鸟类的生态系中抗禽流感病毒抗体的监测是预警、预报我国家禽流感暴发的有效途径，也是十分必要的，同时，血清学的检测结果为我们进一步的分子水平的分析研究提供了明确的靶向。     

榆中地区鸡禽流感H5亚型的血清学调查

2007年4月底,笔者在榆中县进行鸡禽流感春检工作,对23个乡镇的344份血清,应用血凝抑制试验(HI)进行了血清学检测。结果显示,应用于本次血凝抑制(HI)试验的4个血凝单位抗原的稀释倍数为512倍(29);在检测的阳性结果中,鸡禽流感H5亚型HI最高抗体滴度为512(29),主要分布在青城﹑甘草店﹑园子3个乡镇;HI最低抗体滴度为32(25),主要分布在中连川﹑和平﹑上花3个乡镇。血清抗体阳性率以青城乡最高,达100%,血清抗体阳性率以来紫堡乡最低,为35.71%;榆中县总体血清抗体阳性率为74.42%。由此可见,H5亚型禽流感病毒阳性率较高,且抗体滴度也较高,说明该地区大多数家禽对禽流感H5亚型病毒可以产生较强的保护抗体。     

鸡免疫重组禽流感(H5+H7)二价灭活疫苗效果评价

为了掌握重组禽流感(H5+H7)二价灭活疫苗在鸡中的免疫效果,分别在东莞选取5个规模养殖场和14个镇(街)散养鸡免疫疫苗21天后,采集血清样品进行H5亚型和H7N9亚型禽流感病毒抗体检测,结果为H5亚型禽流感病毒(Re-8株)抗体阳性率为79.23%(683/862),H7N9亚型禽流感病毒抗体阳性率为64.15%(553/862)。结果表明,该疫苗在鸡群中能够产生比较好的应答,H5亚型禽流感病毒(Re-8株)抗体阳性率均能达到免疫规范要求的70%以上。H7N9亚型禽流感病毒抗体阳性率,在种鸡场和肉鸡场能到70%以上,但散养鸡抗体阳性率较低,有不能抵御野毒侵袭的风险,还需要进行二次免疫。     

H5亚型禽流感病毒感染犬、猫的流行病学调查

为探讨禽流感与禽类接触动物的关系,对来自东莞各养殖场所的698份犬血清和200份猫血清进行了H5亚型禽流感微量血凝(HA)与血凝抑制(HI)试验,另对与血清一一对应的898份犬、猫喉拭子进行H5亚型禽流感荧光RT-PCR检测试验。结果表明,698份犬血清H5抗体检出率为6.02%,抗体阳性率为0.29%;200份猫血清抗体检出率为2.5%,阳性率为0;898份犬、猫喉拭子中未检测到禽流感H5亚型病毒。     

湘西自治州规模化鸭场H5、H7亚型禽流感病毒抗体水平的检测与分析

为了研究湘西自治州规模化鸭场的高致病性禽流感的免疫情况和潜在的感染风险,笔者于2008年从湘西自治州各县市采集了规模化鸭场血清标本共480份,采用血凝试验和血凝抑制试验对4个免疫了H5亚型禽流感病毒灭活疫苗的规模化鸭场的不同日龄家鸭进行了H5和H7亚型禽流感病毒抗体的检测。结果表明:4个规模化鸭场H5亚型禽流感病毒抗体合格率分别为65.56%(59/90)、67.78%(61/90)、53.33%(48/90)、47.78%(43/90),说明规模化鸭场的H5亚型免疫抗体水平还有待提高,以对家鸭提供确实的保护;H7亚型禽流感病毒抗体阳性率为0,规模化鸭场没有H7亚型禽流感病毒感染。     

重组H5亚型禽流感病毒三价灭活疫苗免疫效果的评价

为了评价重组H5亚型禽流感病毒三价灭活疫苗的免疫效果,在2016年7月至2017年8月期间,对免疫重组H5亚型禽流感病毒三价灭活疫苗(H5N1,Re-6株+Re-7株+Re-8株)的家禽采集了1 999份血清样品,采用血凝与血凝抑制方法进行检测,结果为H5亚型禽流感病毒Re-6株免疫合格率为86.84%,H5亚型禽流感病毒Re-7株免疫合格率71.44%,H5亚型禽流感病毒Re-8株免疫合格率为67.78%。结果表明,免疫重组H5亚型禽流感病毒三价灭活疫苗后,不同毒株的抗体、不同种类的家禽、不同免疫次数的抗体水平均有差异。     

北京地区部分特禽及候鸟禽流感流行病学调查报告

用血凝抑制试验(HI)及病原学检测的方法对北京地区部分特禽及候鸟等42个品种进行了流行病学调查,对非免疫群体的11 个特禽品种288份血清进行检测。结果表明,禽流感H7亚型抗体均为阴性;禽流感H5亚型:白雉阳性率33％,白天鹅阳性率100％,猫头鹰阳性率100％,大雁鹅阳性率72％,野鸭阳性率75％;禽流感H9亚型:信鸽阳性率2096,大雁鹅阳性率61％,野鸭阳性率90％、白天鹅阳性率100％。从血清学上证实,北京地区部分特禽中存在H5、H9亚型禽流感抗体。对免疫过的42个品种2 000份血清进行检测,结果表明,用现有鸡的疫苗免疫特禽能产生较好的免疫应答。     

肉鸡H5、H7亚型禽流感病毒母源抗体消长规律及其对禽流感疫苗接种的影响

为了规范罗斯308肉鸡H5亚型和H7亚型禽流感疫苗免疫程序的制定,研究对不同免疫程序的商品肉鸡进行了血清学调查。结果表明:非免疫肉鸡的H5亚型(Re-8)和H7N9亚型禽流感病毒抗体阳性率均随日龄增长而逐渐下降,两种母源抗体的保护时间均较短。接种H5+H7二价禽流感灭活疫苗前肉鸡的这两种母源抗体阳性率均在70%以上,平均滴度均≥4 log2;接种后各监测时间的两种禽流感抗体阳性率均在70%以下,抗体平均滴度均4 log2,但接种疫苗肉鸡抗体保护时间比不接种肉鸡保护时间长。提示部分商品肉鸡饲养后期存在被H5亚型和H7亚型禽流感病毒感染的风险。     

黑龙江省部分地区散养畜禽流感病毒感染的血清学调查与分析

本研究应用血凝抑制试验（HI），在2005年初，于黑龙江省绥化、海林两地区散养的临床健康的猪、家禽中采集血清样品178份，对其进行了血清学检测，并将获得的血清学检测数据进行了统计学分析。分析结果显示，绥化地区采集的血清样品共计60份，其中家禽中抗H9亚型流感病毒抗体阳性样品24份，占家禽检测总样品数（45份）的53．3％；在海林市地区采集的血清样品共计118份，其中家禽中抗H9亚型流感病毒抗体阳性样品29份，占家禽被检测总样品数（88份）的32．9％。在两地猪群中的血清学检测结果发现，抗H9亚型流感病毒抗体阳性率较高，分别占猪血清检测样品（14／15，19／30）的93，3％和63．3％，两地的畜禽检测中均未检测到H5、H7亚型抗流感抗体。本次试验检测结果表明，在黑龙江省的畜禽养殖中，尤其是猪与家禽当中，存在抗H9亚型流感病毒的抗体，推断可能有该亚型流感病毒的传播；未检到H5、H7亚型流感病毒抗体，在本次检测中可以初步判定在被检测的畜禽当中不存在高致病性禽流感病毒感染与流行。     

安徽省猪群H5亚型禽流感的血清学调查

对安徽省16个地区规模猪场商品猪、散养猪和定点屠宰生猪进行随机抽样,采集血清样品及相应的鼻腔棉拭样品共2588份。首先采用微量血凝抑制试验对血清样品进行H5亚型禽流感抗体检测,然后使用H5亚型禽流感病毒抗原快速检测试剂盒对抗体阳性的鼻腔棉拭样品进行抗原检测。结果显示:(1)在所监测范围内,散养猪和屠宰生猪均未检测到H5亚型禽流感抗体。(2)64个规模猪场1616份血清样品中有11个猪场67份样品检测出H5亚型禽流感抗体,阳性场占17.19%(11/64),各阳性场抗体检出率从10%～50%不等,样品阳性率为4.15%(67/1616);不同地区猪场的抗体检出率分别为:芜湖地区15%(12/80)、安庆地区18%(9/50)、淮北地区15%(9/60)、宣城地区7.14%(10/140)、合肥地区4.62%(18/390)、巢湖地区4%(4/100)、马鞍山地区3.75%(3/80)和黄山地区1.03%(2/194)。(3)从抗体阳性的鼻腔棉拭子样品中均未检测到病毒抗原。表明安徽省多个规模猪场均有H5亚型禽流感抗体阳性猪存在,应当引起高度重视。     

桑树的遗传变异特点及在品种选育中的应用

我国具有悠久的桑树栽培历史,拥有3 000余份桑树种质资源,分属15个桑种和4个变种,并逐渐形成适应不同生长环境的8个生态类型。依据已有的研究结果,综述桑树遗传变异的特点包括:广泛分布、自然有性杂交和异花授粉以及缺乏稳定性选择等,促进了桑树的突变发生,形成遗传变异的多样性;无性繁殖方式产生了丰富的无性系变异;性状遗传值中非加性效应占有较大比例;无性系品种间杂种一代存在复杂的多样性分离和经济性状的普遍退化;存在丰富的多倍体系列和普遍的混倍现象等。对桑树品种选育研究提出建议:基于桑树的高度杂合习性,不仅要重视研究不同品种中加性效应在遗传值中所占比率,更要研究非加性效应所占比率及充分利用的方法;基于桑树遗传变异的多样性和丰富的无性系变异,加强无性系和田间选优育种;利用桑树混倍现象,将培育多倍体特别是三倍体品种作为一条有效的多倍体育种途径。     

Variation in quantity and quality of native forages and grazing behavior of cattle and goats in Tanzania

The study was conducted to assess the effects of seasonal variation in the quality and quantity of pasture and management of livestock exclosures (ngitili) on the grazing behavior of cattle and goats. The study was 2×2×2 factorial design with three independent variables: season (Dry or Rainy), ngitili management (Private or Communal) and animal species (Cattle or Goats). Focal and scan observation methods were used to record different behavioral activities. Vegetation attributes from the study areas were measured in two consecutive seasons. Most key forage species had significant higher crude protein (CP) content and in vitro organic matter digestibility (INVOMD) in rainy than in dry season (P<0.05), but Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) did not vary significantly with season (P>0.05). ADF and NDF were significantly higher in species from communal ngitili than those from private ngitili (P<0.05). Above-ground herbaceous biomass and bulk density (BD) were significantly higher in the rainy season and in the private ngitili than in the dry season and in the communal ngitili respectively. Cattle and goats spent considerably more time grazing and browsing respectively in the rainy season than in the dry season (P<0.05). Cattle foraging activities did not vary significantly (P>0.05) with ngitili management, but goats found to spend considerably more time browsing in the communal ngitili and more time grazing in the private ngitili (P<0.05). Despite the merits of stocking cattle and goats together in the heterogeneous pasture, seasonal variation in forage resources requires investigation of other strategies such as use of multipurpose trees and treatment of crop residues to improve livestock production.     

Evaluation of lysozyme and lactoferrin in lacrimal and other ocular glands of bison and cattle and in tears of bison

OBJECTIVE: To evaluate lactoferrin and lysozyme content in various ocular glands of bison and cattle and in tears of bison. SAMPLE POPULATION: Tissues of ocular glands obtained from 15 bison and 15 cattle and tears collected from 38 bison. PROCEDURE: Immunohistochemical analysis was used to detect lysozyme and lactoferrin in formalin-fixed, paraffin-embedded sections of the ocular glands. Protein gel electrophoresis was used to analyze ocular glands and pooled bison tears by use of a tris-glycine gel and SDS-PAGE. Western blotting was used to detect lactoferrin and lysozyme. RESULTS: Immunohistochemical staining for lactoferrin was evident in the lacrimal gland and gland of the third eyelid in cattle and bison and the deep gland of the third eyelid (Harder's gland) in cattle. Equivocal staining for lactoferrin was seen for the Harder's gland in bison. An 80-kd band (lactoferrin) was detected via electrophoresis and western blots in the lacrimal gland and gland of the third eyelid in cattle and bison, Harder's glands of cattle, and bison tears. An inconsistent band was seen in Harder's glands of bison. Lysozyme was not detected in the lacrimal gland of cattle or bison with the use of immunohistochemical analysis or western blots. Western blots of bison tears did not reveal lysozyme. CONCLUSIONS AND CLINICAL RELEVANCE: Distribution of lactoferrin and a lack of lysozyme are similar in the lacrimal gland of cattle and bison. Differences in other tear components may be responsible for variability in the susceptibility to infectious corneal diseases that exists between bison and cattle.     

Housing of dogs and cats in shelters and kennels in Switzerland

The study deals with the situation regarding housing of dogs and cats in Swiss shelters and kennels. In shelters, dogs were mainly held inside a cubicle with a small outside yard. In kennels, housing of dogs took place mainly in inside rooms. Usually two or three dogs were kept together. Cats were held in rooms, with or without outside yards, mainly in groups; no establishment preferred exclusively the housing in cubicles. Shelters received on average 183 dogs and 262 cats each year. Among them, about a third were lost animals while the remaining ones were relinquished. The study highlights some possibilities for improvements and the great diversity of the establishments regarding their size, infrastructure, housing conditions and aims.     

Ecology and epidemiology of anthrax in cattle and humans in Zambia

Anthrax is endemic in Western and North-western Provinces of Zambia. The disease occurs throughout the year and impacts negatively on the economy of the livestock industry and public health in Zambia. During 1989-1995, there were 1626 suspected cases of anthrax in cattle in Western province and of these 51 were confirmed. There were 220 cases of human anthrax cases in 1990 alone and 248 cases during 1991-1998 with 19.1% and 7.7% case fatality rates, respectively. Interplay of the ecology of affected areas and anthropogenic factors seem to trigger anthrax epidemics. Anthrax has drawn considerable attention in recent years due to its potential use as a biological weapon. In this paper, the history, current status and approaches towards the control of the disease in Zambia are discussed. Quarantine measures restrict trade of livestock and exchange of animals for draught power resulting in poor food security at household levels. Challenges of anthrax control are complex and comprise of socio-political, economical, environmental and cultural factors. Inadequate funding, lack of innovative disease control strategies and lack of cooperation from stakeholders are the major constraints to the control of the disease. It is hoped that the information provided here will stimulate continued awareness for the veterinary and medical authorities to maintain their surveillance and capabilities against the disease. This may lead to a culminating positive impact on livestock and human health in the southern African region.     

犬和猫急性胰腺炎的病因及机制研究进展

胰腺周围脂肪组织和腺泡坏死被认为是急性胰腺炎(Acute pancreatitis,AP)的主要病理特征。胰腺炎轻者不累及其他器官,无并发症,为自限性疾病;重者胰腺出血、坏死、多器官功能衰竭,出现并发症,危及生命。近年来,胰腺炎在犬和猫中发病率非常高,而且病程一般是由急性期转至慢性期,由轻微转至严重。对其发病原因及其发病机制知之甚少,国内外兽医相关文献鲜有报道。论文参考大量研究文献并结合临床经验,综述该病的发病原因和发病机制,以期为临床预防和治疗提供思路。     

甘肃苜蓿田芫菁的种类为害及防治

通过对甘肃苜蓿田芫菁为害调查表明,常见芫菁种类有中华豆芫菁、绿芫菁、苹斑芫菁、腋斑芫菁、豆芫菁、暗头芫菁6种。对其成虫形态特征进行了描述,并列出了检索表。讨论了苜蓿田芫菁的为害性,指出其不仅取食为害,而且因其尸体内含有的斑蝥素,含其尸体的苜蓿草及草产品也会对家畜健康造成危害;因此,干草中不能有有其尸体。最后提出了芫菁的取样调查和防治技术。     

民勤县畜禽寄生虫的种类厘定

勤县是甘肃省的养羊大县,畜牧业发展已成为全县经济发展的支柱产业和农民增收的优势产业,但至今对民勤县畜禽寄生虫病的种类厘定尚未有一篇完整的文献记录。为此,笔者参阅了有关文献,对民勤县畜禽寄生虫的种类和分布状况进行了汇总和归纳,为民勤县畜禽寄生虫病的整体防治措施奠定基础,为有效开展畜禽寄生虫病的防治工作提供重要依据。