鸡新城疫疫苗的研究进展

接种疫苗是有效控制新城疫发生的主要手段。综述了新城疫疫苗的种类及研究进展,对有关研究进行了展望。     

肉鸽新城疫疫苗对比试验

近年来，随着畜牧产业的蓬勃发展，特禽养殖在我市逐渐发展壮大。肉鸽因其营养价值高而越来越受到广大消费者青睐。肉鸽饲养在我市已初具规模，但由于疫病综合防治技术比较滞后，特别是肉鸽新城疫疫苗的使用比较混乱，肉鸽新城疫疫苗的暴发往往给养殖场造成很大的经济损失。为此，我们选择1户中等规模的肉鸽饲养场，就鸽新城疫油乳苗、鸽新城疫灭活苗、鸽新城疫L系苗3种不同疫苗的免疫效果进行了对比试验，筛选出防治肉鸽新城疫的最佳疫苗，为有效防治肉鸽新城疫提供科学依据。     

肉鸽新城疫疫苗对比试验

近年来,随着畜牧产业的蓬勃发展,特禽养殖在我市逐渐发展壮大。肉鸽因其营养价值高而越来越受到广大消费者青睐。肉鸽饲养在我市已初具规模,但由于疫病综合防治技术比较滞后,特别是肉鸽新城疫疫苗的使用比较混乱,肉鸽新城疫疫苗的暴发往往给养殖场造成很大的经济损失。为此,我们选择1户中等规模的肉鸽饲养场,就鸽新城疫油乳苗、鸽新城疫灭活苗、鸽新城疫L系苗3种不同疫苗的免疫效果进行了对比试验,筛选出防治肉鸽新城疫的最佳疫苗,为有效防治肉鸽新城疫提供科学依据。1鸽场情况该场主要是从甘肃省张掖、甘谷引进商品肉鸽,存栏390只,肉鸽包…     

肉鸡新城疫zMlo株苗免疫效果好

<正>近几年,鸡新城疫发生不受日龄限制,发病日龄提前,早的10日龄左右就发病,并且死亡率高,常常在免疫后就发病,或在20～35日龄发病,这是目前肉鸡养殖面临的重要问题。要做好肉鸡新城疫的防控,重点还是应搞好新城疫疫苗的免疫接种。选择安全性高,免疫原性好的疫苗是关键。资深兽医推荐zMlo株疫苗。zMlo株疫苗一是能提高抗体水平,增强抵抗力;二是zMlo株属于肠道型新城疫病毒,可在肠道和呼吸道两个靶位复制、定     

一例肉仔鸡非典型新城疫和大肠杆菌病混合感染的诊治报告

叶大肠杆菌、非典型性新城疫已成为危害肉仔鸡的主要疾病。大肠杆菌为条件性疾病,血清型多,产生耐药性快;非典型性新城疫为副粘病毒病,主要由于疫苗首免时母源抗体过高、免疫不合理、其它疾病干扰、新城疫强毒株毒力不同及机体受到应激等原因而发生和传播。2种传染病混合感染,将给诊断和治疗带来极大不便。1发病情况山东潍坊某鸡场养殖3000羽肉鸡,32日龄时发病。入舍以来该批鸡只长势一直不错,3日龄做过新支二联弱毒苗,14、28日龄曾饮水免疫过2次传染性法氏囊炎疫苗(中等毒力),做完第2次传染性法氏囊炎疫苗后,鸡只状态有所改变,呼吸道症状开…     

当前新城疫的流行特点及防治建议

<正>新城疫(ND)是由新城疫病毒(Newcastle Disease Virus,NDV)引起的一种急性、高度致死性的禽类传染病,是目前严重危害我国养禽业、必须通过疫苗进行防控的重大动物疫病之一。目前NDV只有一种血清型,但研究表明NDV不同毒株之间的抗原性差异正在逐渐加大,再加上生产中新城疫疫苗的使用频繁且混乱,导致近些年     

新型新城疫疫苗研制势在必行

<正>"研究表明,目前常用新城疫疫苗毒株与当前流行毒株基因型不匹配,免疫保护力不足。"2011年11月,在中国畜牧兽医学会禽病学分会上,扬州大学刘秀梵院士指出,研发新城疫新型疫苗势在必行。     

美国研制成功新型新城疫疫苗

<正>前不久,新型新城疫疫苗由美国农业部科学家研制成功。这种新型疫苗不仅降低了新城疫在家禽中的致死率与发病率,同时也可减少该病毒的传播。美国微生物学家余庆中(音译)博士领导的科研团队发现,通过反向遗传技术,他们把传统疫苗内的某个基因置换为目前流行毒株的基因,研制出新型疫苗。此新型疫苗的免疫实验结果显示,可保护家禽免于感染,并且用野毒株感染时,能够降低病毒的散播。     

新城疫苗点眼滴鼻时应注意的问题

正家禽新城疫的免疫存在很多误区,导致免疫失败,成为临床新城疫发病越来越频繁的原因之一。新城疫苗点眼滴鼻时,最常见的问题是疫苗刚滴进眼或鼻内就把鸡放回笼内,而小鸡的习惯性甩头动作会把疫苗甩掉,致使免疫失败。因此作苗时必须等滴     

鸡新城疫疫苗与禽流感疫苗单独免疫和共同免疫后抗体水平的比较

<正>禽流感(AI)和新城疫(ND)是目前影响我国养鸡业发展的主要疫病,在实际生产中主要通过免疫来预防其发生。但在经过正常的免疫程序后,蛋鸡开产后和产蛋高峰期经常会出现新城疫和禽流感的抗体水平同时下降的现象。针对这种情况,养殖户往往同时应用两种疫苗免疫,但免疫效果不尽相同。为此,本实验通过观察对比新城疫疫苗、禽流感疫苗同时免疫时是否存在相互抑制或促进的作用,为蛋鸡免疫计划的制定提供参考。     

陕西省重大动物疫病秋防免疫抗体的检测与分析

猪瘟、口蹄疫、禽流感和新城疫四种重大动物疫病对畜禽业的危害非常严重,目前疫苗免疫是预防和控制动物疫病最有效的途径,免疫抗体检测能很好的反映出免疫效果的好坏。为了及时了解陕西省重大动物疫病免疫状况,2010年11月份在全省11个市(区)的21个县随机采集牛、羊、猪、鸡秋防免疫血清共2359份,按照农业部规定的检测方法,对其进行了重大动物疫病免疫抗体水平的检测,检测结果均达到或超过农业部规定的合格标准,说明陕西省今年秋防动物免疫效果总体较好。     

不同高致病性禽流感疫苗对肉鸡免疫效果观察

应用重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株),禽流感-新城疫重组二联活疫苗(rL-H5株),首免用重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株)、二免用禽流感-新城疫重组二联活疫苗(rL-H5株)对3组肉鸡进行禽流感的免疫效果观察。结果表明:免疫重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株)的效果比免疫禽流感-新城疫重组二联活疫苗(rL-H5株)的效果好;首免用重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株)、二免用禽流感-新城疫重组二联活疫苗(rL-H5株)的效果比免疫重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株)的效果更好。     

斑点叉尾鮰病毒囊膜蛋白ORF6在昆虫细胞中的表达

为构建基于杆状病毒表达系统的CCV新型亚单位疫苗,将CCV的囊膜蛋白基因ORF6克隆至杆状病毒转座载体pFastBacTM 1质粒中,并将阳性重组转座质粒转化进含穿梭载体Bacmid的感受态细胞DH10Bac中,获得重组子rBacmid-ORF6。在脂质体介导下将该重组子转染sf9昆虫细胞,获得重组杆状病毒AC-ORF6。AC-ORF6感染的sf9昆虫细胞,经超薄切片电镜观察,可见重组杆状病毒呈多粒包埋,经间接免疫荧光、Western-blotting检测,CCV的ORF6蛋白可以在感染了AC-ORF6的sf9细胞中表达。研究表明,获得了插入ORF6基因的重组杆状病毒,并且该基因可以在重组杆状病毒介导下在昆虫细胞中表达,从而为基于CCV ORF6的杆状病毒亚单位疫苗研究奠定了基础。     

鲆鲽类渔用疫苗研究现状及展望

我国是世界鲆鲽类养殖大国,近年来产业开始由开放式流水工厂化养殖向循环水工厂化养殖转变,但是受病害问题的困扰,产业转型提升受到巨大的制约,为此探讨疾病有效防控方法成为水产界的紧迫任务之一。目前,鱼病防治仍以化学药物防治为主,生态预防、免疫预防的研究与应用刚刚起步,渔用疫苗具有无残留、不会造成耐药性并能保证环境安全等优点而备受业界的关注。本综述分析了鲆鲽类疫苗的研制应用现状和存在的问题,并对其发展前景作了初步预测,以期为鲆鲽类养殖技术的转型提升,也为工业化养殖建立一条安全、高效的鱼病防控体系提供参考。     

Codon‐optimized expression of fish iridovirus capsid protein in yeast and its application as an oral vaccine candidate

Fish iridovirus causes systemic disease with high morbidity and mortality in various species of wild and farm‐raised fish, resulting in severe economic losses. Recently, frequent outbreaks of iridovirus infection have occurred among cultured fish in many Asian countries, emphasizing the need for a protective vaccine programme or the development of a suitable therapy. In this study, we expressed a recombinant major capsid protein (rMCP) of rock bream iridovirus (RBIV) from yeast using codon optimization. The rMCP in yeast was added to feed in an attempt to induce intestinal mucosal immunity for protection against and/or to reduce the severity of fish iridovirus infection. We found that fish immunized orally with rMCP underwent a successful induction of antibodies (P < 0.05) and were protected (P = 0.0001) against viral challenge. Based upon these results, oral administration of immunogenic protein as an antigen can be considered a useful method for implementation of vaccine programmes against iridovirus as well as other marine viral diseases.     

Exploring the efficacy of vaccine techniques in juvenile sablefish,Anoplopoma fimbria

Wild sablefish, Anoplopoma fimbria, are a valuable commercial species whose populations are declining. Fortunately, sablefish are excellent species for commercial aquaculture. Sablefish raised under high‐density conditions in the marine environment require the use of efficacious vaccines to control disease. Sablefish impacted by disease in net pens may have poor flesh quality and high mortality during grow‐out. As a result, disease can cause financial hardship for sablefish aquaculture operators. The efficacy of a multivalent vaccine preparation for sablefish, administered either by intraperitoneal (i.p.) injection or by immersion, against atypical and typical Aeromonas salmonicida, the causative agents of atypical and typical furunculosis, respectively, was examined. A. salmonicida can affect sablefish at any age and size. Consequently, an efficacious vaccine that can be appropriately and optimally administered to all life stages is desirable. Sablefish vaccinated by immersion at ~1.5 or ~4.5 g with a whole‐cell multivalent vaccine were not protected against either typical or atypical A. salmonicida. Factors that may have contributed to the ineffectiveness of the immersion vaccine are discussed. By contrast, the relative per cent survival (RPS) or potency of the whole‐cell multivalent vaccine injected i.p. in juvenile sablefish at ~50 g against typical and atypical A. salmonicida was 94.3% and 81.7% respectively. The high RPS values indicated that the vaccine successfully initiated an immune response in sablefish upon a second encounter with the pathogen.     

Experimental infection of turbot, Scophthalmus maximus (L.), by Moritella viscosa, vaccination effort and vaccine-induced side-effects

Moritella viscosa is the causative agent of winter ulcers in farmed salmonids and Atlantic cod in countries around the North Atlantic. The bacterium has also been isolated from various marine fish species. Bacterial diseases have been a limiting factor in farming of turbot, but M. viscosa has not so far been isolated. In this study, turbot was shown to be sensitive to M. viscosa infection in experimental challenges. Pathological changes in infected turbot were comparable with those previously described for winter ulcers in salmon. A multivalent commercial salmon vaccine, containing M. viscosa as one of five antigens and a mineral oil adjuvant, did not protect turbot against challenge 13 weeks post-vaccination. Weight gain of vaccinated turbot compared with controls was not reduced 7 weeks post-vaccination. Vaccination did not induce a specific anti-M. viscosa response, while elevated anti-M. viscosa antibody levels were detected both in vaccinated and unvaccinated fish 5 weeks post-challenge. The vaccine did, however, induce an antibody response against Aeromonas salmonicida, another vaccine component. Minor intra-abdominal adhesions were detected in vaccinated fish and fish injected with a mineral oil adjuvant. The measurement of various innate humoral immune parameters did not reveal significant differences between vaccinated and control groups.     

Characterization of Weissella ceti infections in Brazilian rainbow trout,Oncorhynchus mykiss (Walbaum), farms and development of an oil-adjuvanted vaccine

Weissella ceti is an emerging bacterial pathogen that affects rainbow trout, Oncorhynchus mykiss (Walbaum), farms. The aims of this study were to genotype W. ceti strains isolated from distinct geographical origins and to determine the efficacy of an oil-adjuvanted vaccine against the disease. Between 2010 and 2012, outbreaks were recorded in five Brazilian farms, and 34 W. ceti isolates were genetically characterized by repetitive extragenic palindromic PCR, enterobacterial repetitive intergenic consensus sequences PCR and pulsed-field gel electrophoresis. Two different W. ceti vaccines were tested: an aqueous-based whole-cell inactivated vaccine (bacterin) and oil-adjuvanted vaccine. Their efficacy was evaluated in rainbow trout at 30 and 60 days post-vaccination (d.p.v.). W. ceti was found to be a highly homogeneous population in Brazil, with clonally related genotypes. Oil-adjuvanted vaccine exhibited the best (P < 0.05) protection against disease, reaching relative percentage survival (RPS)values of 92% at 30 and 60 d.p.v. Bacterin resulted in RPS values of 67% and 58% at day 30 and 60, respectively. The oil-adjuvanted vaccine provided effective protection against W. ceti infection in rainbow trout.     

Experimental infection of turbot, Scophthalmus maximus (L.), by Aeromonas salmonicida subsp. achromogenes and evaluation of cross protection induced by a furunculosis vaccine

Turbot was shown to be sensitive to injection challenges by Aeromonas salmonicida subsp. achromogenes (Asa). A systemic disease was induced and the bacterium was isolated from various internal organs. Histopathological changes involved haemorrhages, necrosis and degeneration in skin and muscle, haemorrhages and necrosis in kidney, degeneration in the heart muscle, and fusion of the secondary gill lamellae. A polyvalent commercial salmon vaccine, containing A. salmonicida subsp. salmonicida as one of five antigens, did not confer protection in turbot against an experimental Asa infection 13 weeks post-vaccination. Vaccination induced a significant antibody response against Asa cells but not against extracellular products of the bacterium. The results of the study indicate that Asa may be a potential threat to turbot farming and that the development of new turbot vaccines is needed.     

The usage of vaccination and antimicrobial agents for control of Yersinia ruckeri

Abstract. Selected salmonid fish farms in England and Wales were sent a questionnaire designed to collect data on enteric redmouth disease (ERM) vaccination and the usage of antimicrobial agents. The response to the survey was 41·5%. The results indicated that 22% of responding farms have had ERM diagnosed since 1982, half of them have experienced the disease every year since the initial confirmation and it occurs primarily between April and September; mainly in rainbow trout, Oncorhynchus mykiss (Walbaum), of 222/kg-200g. Although larger fish were also affceted. The incidence of ERM coincides with a rise or fall in water temperature, over-crowding, poor water quality or grading. Vaccination against ERM is used on 53% of the responding farms. In addition, 45% of these farms considered immunization to have failed, mainly due to the poor condition of the fish and the low water temperatures at vaccination. On those farms whieh employed vaccination, the commonest ehemotherapeutant used against ERM is oxolinic acid. However, oxytetracycline is the most frequently used antibiotic on farms not employing a vaccine. The use of an antimicrobial agent as a prophylactic or the use of another compound when the first treatment is completed occurred on some farms. The average annual cost for vaccination and treatment has been calculated.