An enzyme-linked immunosorbent assay (ELISA) for the primary diagnosis of foot-and-mouth disease. Characterization and comparison with complement fixation

A sandwich type ELISA for foot-and-mouth disease (FMD) virus types O, A and C was established, using a combination of rabbit anti-146 S and guinea pig hyperimmune antibodies. This method was found to be highly efficient for the detection of both 146 S particles and 12 S subunits. The ELISA was approximately 500 times more sensitive than complement fixation (CF) when examining epithelial samples of FMD vesicles. An early primary diagnosis of FMD was obtained by both CF and ELISA in 19 out of 21 confirmed cases. The remaining 2 cases were initially negative in CF but positive in ELISA.     

口蹄疫O型灭活疫苗对不同母源抗体仔猪血清中抗体及细胞因子水平的影响

为了解不同母源抗体水平对仔猪免疫后抗体消长的影响,以及免疫后细胞因子的变化,使用口蹄疫O型灭活疫苗对40头初生仔猪进行免疫,并于初次免疫后28 d二次免疫,采用液相阻断ELISA方法检测血清中抗体滴度,双抗体夹心ELISA法检测血清IL-8和IL-12水平。结果显示,母源抗体水平越高对于初次免疫后仔猪抗体影响越大;二次免疫后抗体水平可长时间维持较高水平。初次免疫后14 d~28 d,血清中IL-8和IL-12水平上升极显著(P0.01);二次免疫后14~28 d,IL-8水平上升极显著(P0.01),IL-12水平上升不显著(P0.01)。试验表明,母源抗体水平是影响仔猪免疫后抗体消长的因素之一;口蹄疫O型灭活疫苗能有效提高血清中IL-8和IL-12水平。     

中草药红茶菌的制备及其体外抗口蹄疫病毒活性

[目的]研究中草药红茶菌的细胞、乳鼠毒性以及对口蹄疫病毒在体外的抗病毒活性。[方法]将中草药红茶菌过滤,用细胞培养液稀释,分别接种在BHK21细胞上观察细胞生长情况,评价其对细胞的毒性作用。将中草药红茶菌用灭菌水稀释,分别接种3日龄乳鼠,观察乳鼠生长、健康状态和接种部位变化情况,评价其对乳鼠的毒性作用。用稀释的中草药红茶菌与浓度为1000LD_50的口蹄疫病毒等量混合,37℃条件下作用30min,接种3日龄乳鼠,观察乳鼠发病死亡情况,估算中草药红茶菌体外可杀灭口蹄疫病毒的最大使用浓度。用稀释的中草药红茶菌与口蹄疫病毒混合,接种BHK21细胞,观察致细胞病变效应,记录不同稀释度的中草药红茶菌对口蹄疫病毒的杀灭效果。[结果]BHK21细胞和乳鼠试验表明,中草药红茶菌在1：4稀释后,对BHK21细胞无毒性反应,并可有效抑制1000TCID_50口蹄疫病毒在BHK21细胞生长繁殖;1：2稀释的红茶菌微生态制剂对3日龄乳鼠无毒性反应,并可有效杀灭1000LD_50口蹄疫病毒。[结论]中草药红茶菌是一种安全性好且对口蹄疫病毒有较好杀灭作用的口蹄疫预防中草药微生态制剂。     

猪的若干病毒性疾病的防控策略

阐述了猪流感、口蹄疫、猪瘟、蓝耳病、猪圆环病毒以及病毒性肝炎等疾病的病原及当前生产实践中使用的疫苗情况,结合临床实际经验,指出对这些病毒性疾病的防控策略,以期对从业者防控猪病毒性疾病提供参考。     

用口蹄疫灭活苗稀释伪狂犬病、猪瘟活疫苗混合免疫效果评价

为综合评价疫苗混合免疫效果,采用猪口蹄疫OA二价灭活疫苗(Re-O/MAY98/JSCZ/2013株+Re-A/WH/09株)稀释伪狂犬病和猪瘟活疫苗,通过比较疫苗黏度、抗原含量,免疫前后口蹄疫、伪狂犬病和猪瘟抗体水平等方法进行效果评价。结果显示3种疫苗混合后对剂型、黏度、抗原含量无显著影响,混合免疫组与分别免疫对照组相比口蹄疫、伪狂犬病、猪瘟抗体均无差异,综合效果评价推荐采用混合免疫。     

Adrenal-associated changes in experimental sporidesmin poisoning of sheep

Sporidesmin-dosed hoggets which developed photosensitisation were shown to have enlarged adrenal glands and premature involution of the thymus. These sheep also developed high concentrations of plasma cortisol after the onset of photosensitisation. Sporidesmin-dosed sheep which did not show photosensitisation showed less or no adrenal associated changes.     

Application Experiment in the Field of FMD,CSF and HP-PRRS Vaccines Simultaneously Vaccinated at Two Different Sites

In order to explore the optimal immune procedure of foot-and-mouth disease (FMD), classical swine fever (CSF) and highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS) vaccines in backyard pigs in rural areas, field immune experiment was carried out in two towns. Town A used "332" immune procedure, namely, FMD vaccine and CSF vaccine were simultaneously injected at different sides of the neck, and HP-PRRS vaccine was injected 14 days later. Town B used "321" immune procedure, namely, HP-PRRS vaccine and CSF vaccine were mixed together and injected in one side of the neck, and FMD vaccine was injected in the other side of the neck. FMD, CSF and HP-PRRS antibodies were detected by ELISA, and FMDV, CSFV and HP-PRRSV were detected by RT-PCR. The assessment indexes, including the immune density, immune side-reaction rate, death rate of pigs, positive rate of antibody of backyard pigs, positive rate of antibody of slaughter pigs, positive rate of pathogen of backyard pigs, positive rate of pathogen of slaughter pigs and so on, were collected and analyzed. The results showed that, compared with town A used "332" immune procedure, the HP-PRRS immune density, the positive rate of CSF and HP-PRRS antibody of backyard pigs, the positive rate of HP-PRRS antibody of slaughter pigs were significantly increased (P<0.05), while the death rate and the positive rate of HP-PRRSV of slaughter pigs were significantly decreased (P<0.05) in town B used "321" immune procedure. The other major assessment indexes had no significant difference (P>0.05). The results indicated that the immune efficacy of "321" immune procedure was better than that of "332", and it was worthy to be applied in clinical practice.     

口蹄疫表位疫苗的研究进展

口蹄疫是由口蹄疫病毒引起偶蹄动物发生的一种急性、烈性传染病,给发病地区的畜牧业造成巨大的损失,目前应用疫苗来防控口蹄疫仍是最主要的手段。作为一种新型疫苗,表位疫苗是用病毒相关抗原表位制备,可同时携带多个抗原表位及辅助性表位的疫苗,具有安全性好、易操作和可控等优势,受到人们密切的关注。近些年来,对于口蹄疫表位及疫苗的研究取得了很大的进展,现对口蹄疫病毒相关的细胞表位及其以此为基础的表位疫苗的最新进展进行综述,为研制更加安全有效的口蹄疫疫苗提供参考。