Equine Herpesvirus-I Infection in Horses: Recent Updates on its Pathogenicity,Vaccination, and Preventive Management Strategies

Equine herpesvirus-1 (EHV-1) is one of the most common and ubiquitous viral pathogens infecting equines, particularly horses worldwide. The EHV-1 is known to induce not only humoral but also cellular immune responses in horses. Respiratory distress, abortion in pregnant mares, neurological disorders, and neonatal foal deaths represent EHV-1 infection. Despite the limited success of inactivated, subunit, live, and DNA vaccines, over the past few decades, vaccination remains the prime preventive option to combat EHV-1 infection in horses. However, current vaccines lack the potentiality to protect the neurological form of infections in horses. There is desperate necessity to search effectual EHV-1 vaccines that may stimulate not only mucosal and systemic cellular immunity but also humoral immunity in the horses. This review highlights the state of knowledge regarding EHV-1 biology, EHV-1 pathogenesis, and disparate vaccines studied in the past to prevent EHV-1 infection. The review also underlines the best management strategies which certainly need to be adopted by veterinarians in order to avoid and prevent EHV-1 infection and outbreak in horses in the future.     

免疫区小反刍兽疫免疫抗体监测与分析

本文报告应用C-ELISA方法监测小反刍兽疫免疫区山羊、绵羊和牦牛PPR免疫抗体的结果。结果显示:检测免疫山羊血清298份,阳性163份,阳性率54.70%;检测免疫绵羊血清588份,阳性140份,阳性率23.81%;累计检测免疫羊(山羊和绵羊)血清886份,阳性303份,阳性率34.20%;检测免疫区非免疫牦牛血清353份,阳性51份,阳性率14.45%。并对试验结果显示的免疫区羊免疫抗体阳性率偏低、山羊和绵羊免疫抗体阳性率差异大及免疫区接触牦牛PPR抗体呈阳性的检测结果进行了分析。     

集约化养猪场猪瘟免疫程序的研究

以一家正在流行猪瘟的集约化养猪场基本条件完全相同的两个万头商品猪生产线为实验群体,利用兽医流行病学中自然实验的方法,对三种猪瘟免疫程序进行研究,经历了二年共四个实验阶段,从中筛选出适用于集约化养猪场商品猪群有效的猪瘟免疫程序,该程序包括二次免疫,即首免为乳前免疫,二免为３０～３５日龄免疫。     

"全息"穴区注苗对机体免疫应答反应的影响

本研究以羊为实验动物模型，将伪结核棒状杆菌灭活苗分别接种于试验组羊耳背部“全息”穴区和对照组羊体背侧部皮内，然后定期检测供试羊的白细胞总数和淋巴细胞比率，同时采用ＥＬＩＳＡ检测血清中的特异性抗体效价，用氚村票房胸腺嘧啶核苷（＾３Ｈ－ＴｄＲ）掺入法，分别以刀豆素（ＣｏｎＡ）和特异性为刺激因子进行Ｔ淋巴细胞转化试验。结果表明，两组供试羊的白细胞总数均呈一时性增多，但无显著差异；血清中抗体效价、淋巴细胞     

传染性喉气管炎疫苗免疫对鸡红细胞免疫功能状态的影响

选择健康仔鸡40只，随机分为4组，每组10只。Ⅰ组为健康对照组，Ⅱ－Ⅳ组为不同处理的试验组。在45日龄日，Ⅱ级免疫传染性喉气管炎（ILT）疫苗，Ⅲ组免疫ILT疫苗同时肌肉注射中药免疫增强剂Ⅰ，Ⅳ组免疫ILT疫苗同时肌肉注射中药免疫增强剂Ⅱ。分别在免疫前1天、免疫后第3天和第9天，测定各组鸡的红细胞免疫功能状态。结果发现，试验Ⅱ组的鸡在ILT疫苗免疫后3天，RBC－CR1花环率和RBC－IC花环率显著降低，与其他各组比较差异极显著（P＜0．01）。免疫后9天，RBC－CR1花环率和RBC－IC花环率升高到正常水平；而Ⅲ和Ⅳ组，免疫后RBC－CR1花环率高于I组（P＜0．01、P＜0．05）。说明ILT疫苗免疫会引机体红细胞免疫功能的短暂性降低；疫苗免疫的同时使用中药增强剂能够消除红细胞功能短暂性降低的不良反应。     

种鸡新城疫与传染性支气管炎的免疫对策

近几年来,国内两类重要疫病问题严重影响养鸡业的稳定与发展,一类是发生在夏季的鸡群肠炎问题;另一类是发生在低温的冬春季的鸡群呼吸道疫病问题.     

规模化猪场生物安全体系纵深打造探讨

我国是养猪大国,但并不是养猪强国,生产效率较低,养殖水平虽有提高,但与养猪发达国家之间的差距还比较大,其中生物安全意识淡薄、生物安全体系不完善是一个重要因素。生物安全体系是一种防控猪群疫病的综合措施,完善的生物安全体系可有效切断病原与猪群之间的接触,或者有效降低猪群生存环境或机体内病原数量,使得猪群不发病。文章从猪场生物安全体系建设的主要内容来进行阐述,以期为猪场生物安全体系建设提供思路或借鉴。     

低聚糖对幼年藏獒肠道菌群、腹泻和粪便质量的影响

本试验旨在评定3种低聚糖(果寡糖、棉籽糖和木寡糖)对幼年藏獒肠道菌群、腹泻和粪便质量的影响.试验选用平均体重为(10.18±1.66)kg的幼年藏獒12只,随机分成4组,对照组饲喂基础日粮,试验组饲喂在基础日粮中添加0.3%低聚糖(分别为果寡糖、棉籽糖和木寡糖)的日粮,试验期42 d.收集试验0、21和42 d时幼藏獒粪便,进行粪便评分、微生物培养,测定腹泻指数、粪氨、干物质和pH.结果表明:与对照组相比,3种低聚糖都有提高粪便质量的趋势,其中木寡糖组在42 d时效果最好(P<0.05);在42 d时,3种低聚糖组总需氧菌数量和大肠杆菌数量及粪氨含量显著降低(P<0.05)、乳酸杆菌数量显著增高(P<0.05),其中果寡糖组的效果最明显;3种低聚糖有降低pH的趋势.由此可知,低聚糖能一定程度上促进幼年藏獒的菌群平衡、减少腹泻、提高粪便质量,并且果寡糖的添加效果最好.     

Rabies Vaccination: Higher Failure Rates in Imported Dogs than in those Vaccinated in Italy

The current European Union (EU) legislation decrees that pets entering the EU from a rabies‐infected third country have to obtain a satisfactory virus‐neutralizing antibody level, while those moving within the EU require only rabies vaccination as the risk of moving a rabid pet within the EU is considered negligible. A number of factors driving individual variations in dog vaccine response have been previously reported, including a high rate of vaccine failure in puppies, especially those subject to commercial transport. A total of 21 001 observations collected from dogs (2006–2012) vaccinated in compliance with the current EU regulations were statistically analysed to assess the effect of different risk factors related to rabies vaccine efficacy. Within this framework, we were able to compare the vaccination failure rate in a group of dogs entering the Italian border from EU and non‐EU countries to those vaccinated in Italy prior to international travel. Our analysis identified that cross‐breeds and two breed categories showed high vaccine success rates, while Beagles and Boxers were the least likely to show a successful response to vaccination (88.82% and 90.32%, respectively). Our analysis revealed diverse performances among the commercially available vaccines, in terms of serological peak windows, and marked differences according to geographical area. Of note, we found a higher vaccine failure rate in imported dogs (13.15%) than in those vaccinated in Italy (5.89%). Our findings suggest that the choice of vaccine may influence the likelihood of an animal achieving a protective serological level and that time from vaccination to sampling should be considered when interpreting serological results. A higher vaccine failure in imported compared to Italian dogs highlights the key role that border controls still have in assessing the full compliance of pet movements with EU legislation to minimize the risk of rabies being reintroduced into a disease‐free area.     

微生态制剂调控比格幼犬生长性能和肠道菌群的研究

【目的】研究复合微生态制剂对哺乳期比格幼犬生长性能与肠道菌群结构的影响。【方法】选取12只15日龄比格犬,随机分为对照组和微生态制剂组,每组6只。微生态制剂组幼犬每日灌喂犬用微生态制剂20 mL,对照组幼犬灌喂生理盐水20 mL,于试验第0、3、9、12、15、18、21、25、28 d测量体重并计算净增重,第28天采集全血样、血清样和粪样。全血样进行红细胞(RBC)计数和血红蛋白(HGB)浓度测定,血清样检测碱性磷酸酶(AKP)、无机磷(IP)、总胆固醇(TCHO)、甘油三酯(TG)、免疫球蛋白A(IgA)、免疫球蛋白G(IgG)、白介素-1β(IL-1β)、脂多糖(LPS)含量;粪样进行菌群测序,统计Goods coverage指数、Observed species指数和Shannon指数,对样本进行PCoA分析,并统计各样本在门、属、种水平上的物种分布。【结果】与对照组相比,微生态制剂可显著提高幼犬体重(P<0.05),显著增加血清中RBC数量及HGB、AKP和IP含量(P<0.05),促进比格幼犬生长发育;微生态制剂可显著降低血清TG含量(P<0.05),但对...     

Vaccination using phase I vaccine is effective to control Coxiella burnetii shedding in infected dairy cattle herds

The effectiveness of the vaccination of dairy cows combined or not with antibiotics (i.e. oxytetracycline) to control Coxiella burnetii (Cb) shedding at herd level was investigated in 77 Q fever clinically affected herds. In addition to nulliparous heifers’ vaccination, one out of the four following medical strategies was randomly assigned to dairy cows in each herd: vaccination (using a phase I vaccine) alone, vaccination combined with oxytetracycline, oxytetracycline alone or nothing. Their effectiveness to reduce Cb load in quarterly samples of bulk tank milk (BTM) and of pooled milk of primiparous (MP) was assessed through logistic hierarchical models. A significant reduction in Cb load was observed in herds where the vaccination of ≥80% of dairy cows was implemented; whereas the use of antibiotics was uneffective. Our findings support the interest of a whole vaccination strategy and provide evidence for decreasing the use of antibiotics in dairy cattle herds.     

A quantitative assessment of the risk of exposure to bovine spongiform encephalopathy via meat-and-bone meal in Japan

The feeding of meat-and-bone meal (MBM) derived from cattle infected with bovine spongiform encephalopathy (BSE) is a major source of BSE infection. The risks of BSE infection via MBM in Japan were examined quantitatively to estimate infectivity to cattle via MBM derived from a single clinically infected animal being rendered. Three routes of exposure were modeled: (i) feeding cattle concentrates containing MBM as an ingredient, (ii) feeding cattle concentrates contaminated with MBM from non-ruminant feed at feed plants and (iii) directly feeding MBM in supplemental form to cattle on farms. The effectiveness of measures designed to restrict the feeding of ruminants with ruminant MBM (feed restriction) as well as differences in the risk of exposure among regions were examined using the model.

The model revealed that the median total infectivity fed to dairy cattle via MBM derived from one infected animal was approximately 0.49 cattle oral ID₅₀ (5th percentile = 0.43 ID₅₀, 95th percentile = 0.54 ID₅₀). This value was reduced by 55% after the addition of MBM to cattle concentrates was restricted in 1996. The risk of exposure in dairy cattle was twice that in beef cattle. Comparisons of regional differences in exposure risk indicated that the risk was highest in a region where 14 of the 20 BSE cases reported to date were born. Our model suggested that the routes of exposure via MBM were unlikely to result in increased propagation of BSE in Japan. Furthermore, despite some regional variation, the risk of exposure declined further after the feed restriction was imposed in 1996.     

我国苜蓿种子生产存在的问题及其对策

苜蓿种子生产具有明显的地域性[1] 。气候温暖 ,光照充足 ,降雨稀少并有灌溉条件的地区可获得高产优质的种子[2 ] 。在分析了国内外苜蓿种子生产的历史及现状 ,总结我国苜蓿种子生产中存在问题的基础上 ,如何规范我国苜蓿种子生产 ,从苜蓿种质资源的搜集整理、建立优良苜蓿品种更新换代与良种繁育体系、加强优质苜蓿高产栽培技术研究及苜蓿种子质量标准化几个方面 ,阐述了规范我国苜蓿种子生产过程及产品质量的程序。     

肥东县奶牛养殖现状及发展对策

根据肥东县奶牛养殖的调查结果,针对当前奶牛生产在奶价偏低、养殖效益低下、中小养殖场户高产奶牛少、饲养管理水平不高、基础设施不完备、卫生防疫制度不健全等方面存在的问题,结合我县奶牛养殖现状和发展奶牛生产的优势,提出了加快品种改良,实施标准化生产,广开饲料饲草资源,抓好社会化服务,加强疫病防治,加大投入力度等对策。     

A quantitative assessment of the BSE risk associated with fly ash and slag from the incineration of meat-and-bone meal in a gas-fired power plant in Denmark

It has been recommended that meat-and-bone meal (MBM) be incinerated at 850 °C for at least 2 s and the ashes and slag disposed of in controlled landfills, to dispose of animal-derived proteins. Most commonly, the MBM is incinerated in cement works or coal-fired power plants and the ashes and slag are incorporated into the cement or concrete.

Our goal was to assess with a Monte Carlo simulation model the bovine spongiform encephalopathy (BSE) risk to cattle and humans posed by the ash and slag. The results will be used by decision makers to evaluate the need for disposal of the fly ash in controlled landfills and the feasibility of use of the ash by the phosphate and fertilizer industries.

We assumed that all specified risk material (SRM) and MBM produced in Denmark would be incinerated in this gas-fired power plant. Based on observations in 2001, we assumed that, on average, six (range: 0–15) clinical BSE cases each year were rendered into MBM and incinerated. In addition, SRM or carcasses from 0 to 31 (median = 10) BSE-infected-but-undetected animals/BSE case were also incinerated.

The simulations were run on a 1-week basis. Our results suggest that if the slag is collected and re-incinerated the median BSE infectivity remaining in the fly ash per week would be 3.1E−11 cattle ID₅₀. A cattle ID₅₀ is the amount of infectivity that will cause infection in 50% of cattle exposed to it. During the weeks when BSE was infected in the SRM-MBM, the median infectivity in the fly ash was estimated as 8.7E−10 cattle ID₅₀ and 2.9E−12 human ID₅₀. The 95th percentiles were 2.1E−08 cattle ID₅₀ and 5.8E−10 human ID₅₀, respectively. One ton of fly ash would contain ≤1.8E−07 cattle ID₅₀ 95% of the time. These are the potential exposures of the cattle or human populations. The potential exposures of individuals are far less.