北京郊区猪轮状病毒的分子流行病学调查

轮状病毒是婴幼儿和幼龄动物急性肠炎的重要病原。中和试验是目前轮状病毒的血清型主要分型方法,但由于它涉及细胞培养和病毒分离,因而难以用于流行病学调查。近来报道的利用单克隆抗体技术建立的轮状病毒型特异的 ELISA 虽然很有希望,但尚未进入实     

黑龙江省大庆市部分地区牛轮状病毒腹泻的分子流行病学调查

为了对黑龙江省大庆市部分地区犊牛轮状病毒腹泻的流行情况进行调查,应用RT-PCR技术对随机采取的6份犊牛腹泻粪便样品的轮状病毒VP7基因进行扩增,采用多重半套式PCR方法对VP7基因阳性样本进行分型鉴定。结果显示,6份犊牛腹泻粪便样品中牛轮状病毒VP7基因均为阳性;VP7基因阳性样本经RT-PCR分型鉴定,均属于G10型。该研究结果表明大庆地区引起犊牛轮状病毒腹泻的轮状病毒主要为G型,因此需要针对G型轮状病毒加以防控。     

新疆南疆部分规模牛场牛传染性鼻气管炎血清流行病学调查

为了解新疆南疆部分规模化奶牛场牛传染性鼻气管炎感染情况,采用血清流行病学调查方法,对14个规模化奶牛场1 157份成年母牛血清和640份犊牛血清进行牛传染性鼻气管炎抗体ELISA检测。结果显示,群间抗体阳性率为100%,群内成年母牛抗体阳性率为1.25%～95.00%,群内犊牛抗体阳性率为8.70%～95.83%。结果表明,新疆南疆部分规模牛场存在不同程度的牛传染性鼻气管炎感染。     

川西北牦牛新孢子虫感染血清流行病学调查

目的 了解川西北牦牛新孢子虫的感染情况.方法 采用间接ELISA方法对川西北阿坝州8个县1 070份待屠宰牦牛血清中新孢子虫抗体进行检测.结果 被检1 070份血清样品中65份血清新孢子虫抗体呈阳性,样品来源的8个县都检测到了新孢子虫抗体,被检牦牛的血清抗体平均阳性率为6.1％,其中理县(12.2％)的抗体阳性率显著高于平均水平(p＜0.01),马尔康的最低为2.7％.结论 川西北阿坝州各县广泛存在牦牛新孢子虫感染.     

北京地区腹泻仔猪轮状病毒感染的流行病学调查

近年来,腹泻引起仔猪死亡率剧增,直接影响养猪经济效益。引起仔猪腹泻的原因很多,如细菌、病毒、饲料霉菌毒素、产房温度及母猪奶水质量、球虫等。其中,轮状病毒是引起仔猪腹泻的重要病原。为调查北京地区轮状病毒感染状况,于2010年8月至2012年1月从北京大兴、顺义、通县、密云等地的8个猪场获取248头腹泻仔猪粪便,采用胶体金快速诊断试纸法检测轮状病毒抗原,     

国内牛病毒性腹泻的流行病学调查与分析

为了解近年内国内牛病毒性腹泻的流行现状,从2019年1月开始至2020年12月,在全国7个奶牛重点养殖区域的98家规模牛场,共采集了2831份血样.使用血清中和试验方法进行了BVDV血清学检测分析.按采样对象月龄,将样品分为3月龄以下、4～6月龄、7～12月龄和12月龄以上,按牧场规模将样品分为小规模(100～1000...     

鸡志贺氏菌感染的血清流行病学调查

利用研制的鸡志贺氏菌平板凝集抗原及微量平板凝集试验，对我国河南、山东等不同地区35家鸡场具有拉稀病史的670只鸡血清灭活样品进行了检测。通过检测对鸡志贺氏菌病的发病率、流行地区、品种，日龄及其混合感染等进行血清流行病学调查。结果表明：我国部分地区存在有鸡志贺氏菌感染，其血清抗体阳性率较高，达28．3％（155／547）～33．7％（226／670），已远远超过鸡白痢鸡伤寒（1．4％）。目前该病在我国部分地区已广泛流行，不同品种和日龄的鸡均可发生，但血清阳性率存在显著差异，其中固始鸡和罗曼鸡血清阳性率高于其他品种，幼雏血清阳性率高于成鸡。鲍氏血清型阳性率高于痢疾型，并以二者混合感染为主，而该病与鸡白痢鸡伤寒的混合感染很少发生。     

猪A群轮状病毒感染的诊治

<正>猪轮状病毒感染主要是由猪轮状病毒引起的一种急性肠道传染病,主要发生于仔猪。临床上表现为厌食、呕吐、下痢;种猪和大猪以隐性感染为特点。该病在我国和世界各养猪国家普遍存在,多发生于晚秋、冬季和早春,呈地方性流行。北京市某规模化猪场仔猪群出现厌食、呕吐、下痢、脱水等症状,病死率100%,经流行病学调查、临床症状、剖检变化、实验室诊断确     

内蒙古包头市部分规模化牛场BRV流行病学调查

为了解内蒙古自治区包头市部分规模化牛场牛轮状病毒(BRV)的流行情况,在包头市部分规模化牛场采集275份血液样本和300份粪便样本,采用RT-PCR和ELISA方法对血液样本和粪便样本进行牛轮状病毒抗原和抗体检测。结果显示,BRV抗原总阳性率为21.34%,抗体总阳性率为4.00%。在检测样品中,0～2月龄犊牛的抗原阳性率和抗体阳性率均最高,分别为51.00%和10.00%,本研究检测结果可为规模化牛场牛轮状病毒的防控提供参考。     

我国部分地区蛋鸡群鸭源鸡杆菌血清流行病学调查

为了解鸭源鸡杆菌(Gallibacterium anatis)在我国部分地区鸡群中的感染状况,本实验采用G.anatis微量凝集试验对我国河南、山东和山西等不同地区的1 314份鸡血清样品进行了G.anatis感染的血清流行病学调查,对G.anatis的感染率、感染品种、日龄等进行分析。结果表明:我国河南、山东和山西等地鸡群均存在G.anatis感染,其中G.anatis血清Ⅰ型抗体阳性率为11.95%,G.anatis血清Ⅱ型抗体阳性率为23.29%,G.anatis血清Ⅳ型抗体阳性率为9.82%。不同省份的鸡群感染G.anatis的血清阳性率存在一定差异,河南、山东和山西的血清阳性率分别为23.12%、25.27%和52.94%。对河南地区不同品种和日龄鸡的调查表明,均存在不同程度的感染,但血清阳性率有显著差异,表现为罗曼鸡的血清阳性率比海兰鸡高,开产前蛋鸡的血清阳性率低于开产后的血清阳性率。     

A serologic survey of bovine rotavirus infection in Italy

Serum neutralization tests conducted by microtiter procedure on 2970 serum samples from calves, heifers and adult cows from representative regions of Italy indicate that rotaviruses, and the infection which they cause, existed in Italy long before the virus was isolated. At the present time the infection is distributed fairly uniformly throughout the cattle population with both sexes and all age groups being equally susceptible.     

福建省龙岩市部分地区猪伪狂犬病野毒感染血清学调查

为了探究福建省龙岩地区的2018年猪伪狂犬病野毒感染及流行概况,本试验随机选取龙岩新罗区、连城县、武平县以及长汀县的部分规模化猪场共21个,应用ELISA法对763份血清样品PRV g E抗体进行血清学调查。结果显示样品检测总阳性率为30.41%,其中保育猪、育肥猪、能繁母猪及后备母猪的阳性率分别为:25.29%、30.98%、30.85%、31.75%;用SPSS19.0对其进行差异显著性分析,结果显示不同阶段的猪群gE抗体阳性率差异不显著(P=0.741>0.05);各场场均阳性率为31.89%;各地区阳性率分别为:41.58%、18.18%、30.14%、26.29%,场均阳性率分别为41.14%、23.50%、29.60%、33.33%,对其进行差异显著性分析,结果表示不同地区之间gE抗体阳性率差异极显著(P=0.0003<0.001),即各地区之间伪狂犬病野毒感染情况差异较大,部分地区更需要加强其控制和净化措施。     

Molecular characterization of a novel bovine group A rotavirus

In this study, by partial sequence analysis of the genome segments encoding VP5* and VP7, we characterized a novel bovine group A rotavirus, namely, Tak2, that was detected from adult cattle diarrhea in Tochigi Prefecture, Japan. The nucleotide (nt) and deduced amino acid (aa) sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 of Tak2 revealed a low identity with those of group A rotaviruses carrying previously published P and G type specificities (VP5*: nt identity, 61.6%-67.6% and aa identity, 58.0%-71.4%; half of the amino terminal portion of VP7: nt identity, 57.8%-73.5% and aa identity, 61.2%-70.9%). Additionally, phylogenetic analysis of the nt sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 revealed that Tak2 formed a branch separate from the established P and G types. These results suggested that Tak2 could possess novel P and G types yet not reported among group A rotaviruses.     

Epizootiology of bovine rotavirus infection.

Published information on rotaviruses as pathogens, the source of virus infection and the method of transmission of infection under normal conditions are reviewed. The antigenic differences between rotavirus isolates from children, calves, pigs, foals and mice are discussed. Bovine rotaviruses isolated in the USA and the UK were shown to be closely related antigenically and the US vaccine strain protected calves from challenge with the UK rotavirus. Nineteen normally reared calves, with 20 or more ZnSO4 units of serum delta globulin, were susceptible to rotavirus inoculation at two days of age. They developed diarrhoea, showed body weight loss but recovered. Three calves with less than 10 ZnSO4 units of serum delta globulin developed diarrhoea and died. In a serological survey of 654 adult cows and calves from three herds, between 2 per cent and 37 per cent of individuals in a group had low rotavirus antibody titres and were probably susceptible to rotavirus infection. These were found in all age groups of animals studied, whether or not the group had suffered a recent rotavirus epizootic. It was not possible to predict whether an epizootic would develop on the basis of a serological survey.     

Longitudinal survey of rotavirus infection in calves

A longitudinal survey of rotavirus infection in heifer calves was carried out on a closed Friesian dairy herd over two successive calving seasons. Rotavirus was detected by electron microscopy in the faeces of 45 of 57 (79 per cent) calves examined. On average the virus was first detected at 6.1 days of age. Clinically the disease associated with rotavirus infection was of mild to moderate severity. Only one infected calf required intravenous fluid therapy. Diarrhoea or excretion of abnormal faeces was associated with rotavirus infection in 58 per cent of infected calves, while in the remaining 42 per cent infection was subclinical. The cycle of rotavirus infection was broken by thorough cleansing and disinfection of the calf house.     

Serological survey of bovine herpesvirus type 1 infection in China

To understand the nationwide seroprevalence of bovine herpesvirus type 1 (BoHV-1) infection of cows in China, 1344 sera of dairy cows from 29 provinces and 765 sera from 6 herds in Hubei province were collected with stratified random sampling. Another 483 sera from imported cows were included. The serum antibody was tested by BoHV-1 gG ELISA. The results demonstrated that the overall nationwide seroprevalence was 35.8% (481/1344), while the prevalence for individual province ranged from 12.1% to 77.8%. Although each province had positive samples, the prevalence was clustered in areas based on the cow population size. In Hubei Province, the overall seroprevalence was 22.2% (170/765) while the prevalence for individual farms varied greatly from 0.0% to 41.5%. The sera from imported cows had a moderate prevalence of 21.7% (105/483).     

重庆市禽白血病及禽网状内皮组织增生症的血清流行病学调查

禽白血病和禽网状内皮组织增生症均为禽的肿瘤性免疫抑制疾病,是危害养鸡业的两种非常重要的病毒性传染病。为调查重庆市肉鸡中禽白血病及禽网状内皮组织增生症的流行情况,在北碚区、涪陵区、开县、垫江县、潼南县五个区（县）的8个活禽交易市场采集260份血清样本,采用酶联免疫吸附试验检测了所有血清中禽白血病病毒（ALV）和禽网状内皮组织增生病毒（REV）的抗体。检测结果显示：禽白血病病毒和禽网状内皮组织增生病毒抗体阳性率分别为16.5%（43/260）和5%（13/260）,双抗体阳性率为4.61%（12/260）。与全国其他地区相比,重庆市肉鸡中这两种病原的感染率相对要低,但仍应重视这两种疾病的防控,以控制病原的进一步传播。     

2019年滨州地区及周边规模化场牛支原体血清流行病学调查

[目的]为了了解山东省滨州地区及周边规模化牛场支原体流行的基本情况,[方法]对该区域14个规模化奶牛场和肉牛场进行了血清采集,采用牛支原体IgG抗体ELISA检测方法进行牛支原体血清抗体检测,并使用SPSS 20进行卡方统计学检验。[结果]山东省规模化牛场的牛支原体IgG抗体总阳性率为77.86%,奶牛场的阳性率为74.29%,肉牛场的阳性率为81.43%,奶牛场牛支原体IgG阳性率与肉牛场的统计学差异不显著（P>0.05）;奶牛场不同场区,肉牛场不同场区之间,牛支原体的IgG阳性率差异显著（P<0.05）。[结论]山东省滨州地区及周边规模化牛场存在不同程度的牛支原体感染,牛支原体感染可能成为危害国内规模化奶牛场奶牛健康的主要疫病之一。     

Prevalence of bovine group A rotavirus shedding among dairy calves in Ohio.

Fecal samples were collected from 450 neonatal calves, ranging from 1 to 30 days old, between May, 1988 and May, 1989 to estimate the prevalence of bovine group A rotavirus in a stratified random sample of Ohio dairy herds. Calves were from 47 dairy herds chosen to be representative of Ohio herds. Bovine group A rotavirus was detected in fecal samples by a cell culture immunofluorescence test (CCIF) and ELISA. Of 450 samples tested, 46 (10%) were positive by CCIF and 67 (15%) were positive by ELISA. The agreement beyond chance between the 2 assays was good (kappa = 0.65). The overall prevalence rate of rotavirus shedding was 16.4% (74/450). Forty-three percent (29/67) of the samples positive by ELISA were subgroup 1, none were subgroup 2, and the remaining 57% (38/67) could not be assigned to either subgroups 1 or 2. Thirty herds (62.5%) had at least 1 group A rotavirus-positive calf (mean number of samples per positive herd = 12.4), and 17 herds (37.5%) had no rotavirus-positive calves (mean number of samples per negative herd = 6.0). A live oral rotacoronavirus vaccine was used in neonatal calves of only 1 herd and 3 of 17 (17.6%) calves from this herd were positive for group A rotavirus. The percentage of the rotavirus-positive fecal samples from all calves (n = 450) when stratified by fecal consistency was as follows: 28.3% (13/46) had liquid feces; 25.6% (10/39) had semiliquid feces; 23.4% (22/94) had pasty feces; and 10.7% (29/271) had firm feces.(ABSTRACT TRUNCATED AT 250 WORDS)