Comparison of adjuvants with respect to serum IgG antibody response in orally immunized chickens

We have previously shown that oral immunization with non-replicating antigens hardly induced serum IgG antibody response in chickens and addition of sodium fluoride (NaF) to the immunogen markedly improved their immunological states. In the present study, taurine, lithium and Quillaja saponin (Q-SAP) were compared with NaF with respect to their enhancement of serum IgG antibody response in chickens after oral immunization. The antibody titer of chickens which received Q-SAP as the mucosal adjuvant tended to be higher than that of chickens which received antigen plus NaF. Simultaneous administration of antigen with lithium or taurine elicited a higher antibody titer in chickens compared to those of chickens orally immunized with antigen alone, but the effect of these two adjuvants was less efficient compared with that of NaF. These results suggested that Q-SAP as well as NaF is useful as an oral adjuvant for chickens.     

Indirect ELISAs based on recombinant and affinity-purified glycoprotein E of Aujeszky's disease virus to differentiate between vaccinated and infected animals

Two indirect ELISAs for the detection of antibodies against glycoprotein E (gE) of Aujeszky's disease virus (ADV) in sera have been developed. The rec-gE-ELISA is based on the E. coli-expressed recombinant protein containing the N-terminal sequences of gE (aa 1-125) fused with the glutathione S-transferase from Schistosoma japonicum. The affi-gE-ELISA is based on native gE, which was purified from virions by affinity chromatography. The tests were optimised and compared with each other, as well as with the recently developed blocking gE-ELISA (Morenkov et al., 1997b), with respect to specificity and sensitivity. The rec-gE-ELISA was less sensitive in detecting ADV-infected animals than the affi-gE-ELISA (sensitivity 80% and 97%, respectively), which is probably due to the lack of conformation-dependent immunodominant epitopes on the recombinant protein expressed in E. coli. The specificity of the rec-gE-ELISA and affi-gE-ELISA was rather moderate (90% and 94%, respectively) because it was necessary to set such cut-off values in the tests that provided a maximum level of sensitivity, which obviously increased the incidence of false positive reactions. Though the indirect ELISAs detect antibodies against many epitopes of gE, the blocking gE-ELISA, which detects antibodies against only one immunodominant epitope of gE, showed a better test performance (specificity 99% and sensitivity 98%). This is most probably due to rather high dilutions of the sera used in the indirect gE-ELISAs (1:30) as compared to the serum dilution in the blocking gE-ELISA (1:2). We conclude that the indirect gE-ELISAs are sufficiently specific and sensitive to distinguish ADV-infected swine from those vaccinated with gE-negative vaccine and can be useful, in particularly affi-gE-ELISA, as additional tests for the detection of antibodies to gE.     

休克病畜的综合疗法

休克的特征是全身灌流不足和重要器官组织缺氧而引起的一种急性循环障碍。其临床症状包括:心搏过速,毛细血管的再充盈时间延长,血压降低,脉搏微弱甚至感觉不到,肌无力,感觉中枢受抑制,体温下降,呼吸加快,粘膜苍白或发绀,瞳孔散大和尿量减少.     

在温室里培育落叶松实生苗

在国家的欧洲地区广泛采用从塑料薄膜温室里培育实生苗的方法,这就能在短期内比苗圃获得更加优质的苗木。 1973～1976年,我们在克拉斯诺雅尔斯克边区的耶麦尔扬诺夫林业局研究了利用塑料薄膜覆盖的条件及其对种子在土壤中发芽率的影响以及西伯利亚落叶松(Larixsibrica Led.)实生苗的生长情况。该树种子于五月中旬在温室和露地上播上了,深度为0.5—1厘米。播前把种子在水里浸泡18小时,并用0.5％的高锰酸钾溶液消毒。第一个方案是在一公顷播种面积上施入200公斤氮、100公斤磷和200公斤钾(100％),第二个     

Light and hormones: interchangeability in the induction of nitrate reductase

Suitable concentrations of kinetin and gibberellic acid permit induction of nitrate reductase in leaves of tobacco in the dark. Hormone sprays eliminate the need for light induction of the enzyme. The concentration of gibberellic acid required for optimal induction varies according to the concentration of kinetin supplied.