Olson D P, Waxler G L
Am J Vet Res. 1977 Aug;38(8):1177-81.
The immune responses of 26 Angus-Hereford fetuses and neonates to Escherichia coli O26:K60:NM were studied after bacterin or saline solution was injected (in utero) into the amniotic fluid. Calves were euthanatized at birth or were orally revaccinated; some were challenge exposed with live organisms. The hemolytic plaque assay was used to determine the presence of cells producing immunoglobulins M, G1, and G2 (IgM, IgG1, and IgG2) in 4 segments of the small intestine, mesenteric lymph nodes, and spleen. The passive hemagglutinin activity of intestinal washings was also determined. Anti-O26 passive hemagglutinin activity in the intestinal washings of principal calves was greater than in that of control calves, but in a given segment of the small intestine, usually this activity was relatively small and less consistent than the plaque-forming response. Greater numbers of plaque-forming cells were observed in the small intestine of 14 of the 15 principal calves when compared with the control calves tested.
在向羊膜腔内注射（子宫内）菌苗或盐溶液后，研究了26头安格斯-赫里福德胎儿和新生儿对大肠杆菌O26:K60:NM的免疫反应。犊牛在出生时安乐死或口服再次接种疫苗；一些犊牛用活生物体进行激发暴露。采用溶血空斑试验来确定小肠4个节段、肠系膜淋巴结和脾脏中产生免疫球蛋白M、G1和G2（IgM、IgG1和IgG2）的细胞的存在情况。还测定了肠冲洗液的被动血凝活性。主要犊牛肠冲洗液中的抗O26被动血凝活性高于对照犊牛，但在小肠的特定节段，通常这种活性相对较小，且不如空斑形成反应一致。与测试的对照犊牛相比，在15头主要犊牛中的14头的小肠中观察到了更多的空斑形成细胞。
