Leyk W, Schliesser T, Oei H L
Zentralbl Bakteriol Orig A. 1975;231(1-3):223-8.
In chick embryos 7 days after cultivation, the effect of chloramphenicol, streptomycin, tylosin (0.5 to 32 mg/egg), and of penicillin (100 to 10000 IE/egg) on the process of replication of C.b. in the yolk sac was examined. The ELD50 and the EID50 were examined according to REED and MUENCH. The demonstration of coxiellae was performed microscopically. The results of the examinations are summarized in fig. 1 to 3. In infected untreated controls, the titres of the ELD50 were found at about 10(4) and those of the EID50 at 10(7). The best inhibition was obtained by means of chloramphenicol. In this case, neither a letality of embryos nor an infectivity of eggs was demonstrable by administration of 16 mg/egg. Streptomycin had a similar effect on the letality of embryos like chloramphenicol, but coxiellae were still microscopically demonstrable at doses of 16 and 32 mg/egg. A smaller effect had tylosin so that even after an administration of 32 mg/egg, a minimal letality of embryos and a minimal infectivity of eggs remained. Almost no inhibition was obtained by means of penicillin. Even at 10000 IE/egg, the letality of embryos was diminished only by 1 log 10 and the infectivity of eggs by about 3 log 10. After application of chloramphenicol, streptomycin, and tylosin, the embryos in infected eggs died regularly 1 to 2 days later than those in untreated infected controls with the same titres. Using penicillin, this effect could not be observed.
在培养7天后的鸡胚中，研究了氯霉素、链霉素、泰乐菌素（0.5至32毫克/枚鸡蛋）和青霉素（100至10000国际单位/枚鸡蛋）对鸡胚卵黄囊中伯氏考克斯体复制过程的影响。按照里德和门奇的方法检测了半数致死剂量（ELD50）和半数感染剂量（EID50）。通过显微镜观察考克斯体。检查结果汇总于图1至3。在未处理的感染对照中，ELD50的滴度约为10⁴，EID50的滴度为10⁷。氯霉素的抑制效果最佳。在这种情况下，给予16毫克/枚鸡蛋时，既未观察到胚胎死亡，也未检测到鸡蛋具有感染性。链霉素对胚胎死亡率的影响与氯霉素相似，但在16毫克/枚鸡蛋和32毫克/枚鸡蛋的剂量下，仍可通过显微镜观察到考克斯体。泰乐菌素的效果较小，以至于即使给予32毫克/枚鸡蛋，仍有最低限度的胚胎死亡和鸡蛋感染性。青霉素几乎没有抑制作用。即使在10000国际单位/枚鸡蛋的剂量下，胚胎死亡率仅降低1个对数级，鸡蛋感染性降低约3个对数级。应用氯霉素、链霉素和泰乐菌素后，感染鸡蛋中的胚胎比相同滴度的未处理感染对照中的胚胎通常晚1至2天死亡。使用青霉素时，未观察到这种效果。
