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1.
京海黄鸡杂交组合亲本鸡球虫抗性指标的比较   总被引:1,自引:1,他引:0  
为研究京海黄鸡杂交组合亲本BB鸡与FF鸡鸡球虫病抗性的差异,试验选取BB和FF公鸡各30只,饲养至9日龄时,每个群体随机分为免疫组(n=15)和非免疫对照组(n=15),分组当天免疫组京海黄鸡杂交组合亲本按正典鸡球虫病四价活疫苗说明书要求接种鸡球虫疫苗,疫苗免疫后第8天采用生物素双抗体酶联免疫吸附法(ELISA)测定免疫组和非免疫对照组8个血浆球虫抗性指标,并进行差异显著性检验。结果显示,BB鸡免疫组过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和白介素17(IL-17)的含量显著高于FF鸡免疫组(P0.05);BB杂交组合亲本免疫组CAT含量极显著高于对照组(P0.01),SOD含量显著高于对照组(P0.05);FF杂交组合亲本免疫组CAT和谷胱甘肽过氧化物酶(GSH-Px)含量均显著高于对照组(P0.05)。综合分析结果表明,BB鸡免疫效果优于FF鸡群体,BB鸡球虫病抗性优于FF鸡群体。  相似文献   
2.
为调查规模化猪场不同年龄猪群中2型猪链球菌(S.suis 2)抗体水平,本研究采用以荚膜多糖为抗原的间接ELISA对来自广西地区母猪群、肥猪群、生长猪群共1 908份血清样品进行了S.suis 2抗体检测和分析。结果显示:成年猪群中抗S.suis 2的抗体水平普遍较高,种猪场母猪血清抗体阳性率可高达95%以上,不同地区屠宰场的育肥猪血清抗体阳性率在39.2%~97.5%。对不同日龄仔猪群抗体水平检测分析显示:14日龄~42日龄期间,抗体水平随仔猪日龄的增长而呈逐渐下降的趋势;而42日龄~130日龄期间,抗体水平随日龄的增长而呈逐渐上升的趋势。此外,经产母猪群抗体水平略高于后备母猪群,并且随胎次的增加,抗体的离散度缩小。以上结果表明S.suis 2抗体在仔猪生长阶段的空白期即42日龄时,仔猪群抗体水平最低。因此,在这个阶段和之前做好S.suis的预防和免疫工作对猪群链球菌病的防控至关重要。  相似文献   
3.
In an on‐farm study, 40 weaned piglets aged 3 weeks were vaccinated with Lawsonia intracellularis vaccine orally, IM or IP while a fourth group remained unvaccinated. All vaccinated animals showed increased serum levels of L. intracellularis‐specific IgG antibodies, but significantly elevated concentrations of specific IgG, IgA and cytokines were generated in ileal mucosal secretions from the orally and IP vaccinated pigs when examined at 17 days after vaccination.  相似文献   
4.
The authors analysed epidemiological data of the Hungarian tick-borne encephalitis epidemic from the past seven decades. A total of 911 meningitis serosa cases were described from 1930-1950 s by local hospital physicians, indicating that the virus had been present in the country decades before its official identification in 1952. The virus spread freely in the 1950s–1960s, occupying almost all habitats where ticks occurred in large numbers. The increasing number of cases drove authorities to classify this illness as a notifiable disease in 1977 and to organize the first measures to stop the epidemic. Statistical analysis revealed that the large-scale vaccination launched from the 1990s was responsible for the sharp decrease in the number of human cases from 1997. A significant negative correlation was found between the number of vaccine doses sold and human cases 6 years later. The TBEV endemic area covers 16.57% of the territory and 16.65% of the population of the country. In the last 10 years, 186,000 vaccine doses/year in average were enough to keep the incidence of human TBEV infections between 0.45 and 0.06/100,000 persons. A 20-year-long study found evidence for easing clinical signs in TBEV-infected hospitalized patients. Statistics found a sharp decrease in the number of samples sent for TBEV diagnosis after 1989. Male dominance of patients was characteristic of the epidemics since the 1940s, but now analysis of detailed data from the 1981–2021 period (60.5%–87.5%) proved the statistical significance of this dominance. Obviously, the voluntary vaccination programme was the tool which broke the spread of the epidemic. Widespread public awareness of the disease and the tick vector, probable evolutionary spread of less pathogenic virus strains supplemented with the vaccination campaign led to a negligible level of human TBE cases in Hungary in the last years.  相似文献   
5.
禽流感病毒(Avian influenza virus,AIV)因其具有变异性强、亚型种类多、感染宿主多样性等特点,对畜牧业发展及公共卫生安全具有巨大的影响。目前,传统灭活疫苗在预防禽流感中虽起着重要作用,但仍存在免疫失败、多次接种及易出现不良反应等弊端,因此,研制新型疫苗来弥补传统疫苗的不足非常有必要。纳米颗粒疫苗具有包裹性好、结构稳定、靶向性高和免疫原性强等优点,可作为新型流感病毒疫苗的候选。笔者首先介绍了禽流感难以防控的原因及纳米疫苗的特点,然后对病毒样颗粒疫苗、自组装蛋白疫苗、聚合物纳米颗粒疫苗、无机纳米颗粒疫苗及纳米颗粒的毒性机制方面进行综述,概述了近年来AIV纳米颗粒疫苗的研究进展,并简述了采用不同抗原、不同纳米材料及不同给药方式对免疫效果的影响,结合目前纳米疫苗的研究,预测了未来纳米颗粒疫苗可作为AIV防控的一种新途径,对禽流感纳米疫苗在兽医临床的应用前景进行了分析和展望。  相似文献   
6.
The effect of a standard, single dose therapy with tulathromycin was investigated on the postvaccinal humoral and cellular immune response in pigs vaccinated against swine influenza. Forty‐five pigs, divided into 3 groups, were used (control not vaccinated (C, n = 15), control vaccinated (CV, n = 15), and experimentally received tulathromycin (TUL, n = 15)). For vaccination of pigs, an inactivated, commercial vaccine was used. Pigs from TUL group received single dose of tulathromycin intramuscularly, at the recommended dose (2.5 mg/kg body weight). Pigs from TUL and CV groups were vaccinated at 8 and 10 weeks of age. The specific humoral and cellular immune response against swine influenza virus (SIV) was evaluated. The results of present study showed that humoral postvaccinal response after vaccination against SIV can be modulated by treatment with tulathromycin. In pigs from TUL group, the significantly higher titers of anti‐SIV‐specific antibodies were observed 4 and 6 weeks after booster dose of vaccine. Simultaneously, T‐cell‐mediated immune response against SIV was not affected by tulathromycin. Our recent study confirmed the importance of defining the modulatory activity of tulathromycin because of its influence on the immune response to vaccines. Since the antibodies against hemagglutinin are crucial for the protection against SIV, the present observations should prompt further studies on the practical significance of recent results in terms of clinical implications (postvaccinal protection) in the field conditions.  相似文献   
7.
Rabies is endemic in wildlife or domestic carnivore populations globally. Infection of domestic dogs is of particular concern in many areas. In regions where domestic animals are at risk of exposure to rabies virus, dogs should be routinely vaccinated against rabies to protect both pet and human populations. Many countries require demonstration of an adequate level of serum rabies neutralizing antibodies to permit entry of dogs during international travel. We analysed rabies titres of dogs seeking travel certification in Israel to assess demographic and vaccine history factors associated with antibody titres below the acceptable threshold for travel certification. Having received only one previous rabies vaccination and a longer duration since the most recent vaccination was received were primary risk factors for not achieving an adequate rabies virus neutralizing antibody titre for travel certification. These risk factors had stronger effects in younger animals, but were consistent for dogs of all ages. In particular, these findings reiterate the importance of administering at least two rabies vaccinations (the primo vaccination and subsequent booster) to ensure population‐level protection against rabies in dogs globally.  相似文献   
8.
The Eurasian wild boar (Sus scrofa) is a reservoir for tuberculosis (TB) in which vaccination is a valuable tool for control. We evaluated the protection and immune response achieved by homologous and heterologous regimes administering BCG and heat-inactivated Mycobacterium bovis (IV). Twenty-one wild boar piglets were randomly allocated in five groups: Control, homologous BCG, homologous IV, heterologous IV-BCG, heterologous BCG-IV. Significant 67% and 66% total lesion score reductions were detected in homologous IV (IVx2) and heterologous IV-BCG groups when compared with Control group (F4,16 = 6.393, p = 0.003; Bonferroni Control vs IVx2 p = 0.026, Tukey Control vs IV-BCG p = 0.021). No significant differences were found for homologous BCG (although a 48% reduction in total lesion score was recorded) and BCG-IV (3% reduction). Heterologous regimes did not improve protection over homologous regimes in the wild boar model and showed variable results from no protection to similar protection as homologous regimes. Therefore, homologous regimes remain the best option to vaccinate wild boar against TB. Moreover, vaccine sequence dramatically influenced the outcome underlining the relevance of studying the effects of prior sensitization in the outcome of vaccination.  相似文献   
9.
To develop an effective vaccine against porcine circovirus type 2 (PCV2), ORF2 gene was cloned into a Lactobacillus plantarum (L.plantarum) pSCPSP under the control of a SCP promoter to construct recombinant plasmid pSCPSP-Cap that was transformed into LP1 by electroporation. Extracellular expression of the Cap protein was confirmed by SDS-PAGE and Western blotting analysis. Afterwards, 8-week-old SPF BALB/c mice were randomly divided into control group, carrier group, lavage group, group of drinking water and inactived vaccine group. After 14,28,42 and 56 d, mice serums were collected to evaluate the level of specific antibody by SDS-PAGE and Western blotting. Eventually, SDS-PAGE and Western blotting results indicated that the Cap protein of PCV2 could be efficiently expressed in L. plantarum, expression of protein molecular weight was 28 ku and with good immunogenicity. In addition, higher levels of specific antibody in the serum of mice was observed by oral administration with L. plantarum expressing the PCV2 Cap antigen (P<0.05). In conclusion, the ORF2 gene of PCV2 could be successfully expressed in recombinant L. plantarum and expressed protein with good biological activity, which would lay the foundation for the development of PCV2 oral vaccination.  相似文献   
10.
牛结节性皮肤病(LSD)是《中华人民共和国进境动物检疫疫病名录》中的一类传染病,在新疆出现之后迅速在全国范围扩散,对我国的奶牛和肉牛养殖业造成严重经济损失。LSD主要通过在边境地区的动物贸易或虫媒活动传入未发生疫情的国家,疫苗接种被认为是防控 LSD疫情最有效的方法之一。各国根据本土疫情的传播情况,制定了不同的疫苗接种计划,目前用来预防LSD的疫苗主要为针对不同病原的减毒活疫苗。但是,在防控LSD的同时也造成了生物安全风险,导致重组疫苗样毒株引发的疫情从中亚向东亚迅速蔓延。只有将切断传播途径、保护易感动物和管控生物安全相结合,才能有效预防LSD疫情爆发,促进养殖业的繁荣发展。  相似文献   
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