Leonard F C, Quinn P J, Ellis W A, O'Farrell K
Teagasc, Moorepark Research and Development Centre, Fermoy, County Cork.
Res Vet Sci. 1993 Sep;55(2):195-202. doi: 10.1016/0034-5288(93)90081-p.
The shedding of Leptospira interrogans serovar hardjo in the urine of cattle and the local and systemic response to these organisms was monitored in experimentally and naturally infected animals. Twenty yearling heifers, 10 infected by the instillation of leptospires into the conjunctival sac (supraconjunctival route) and 10 infected intrauterinely, shed leptospires for up to 60 weeks after infection. Five of 15 naturally infected pregnant heifers with microscopic agglutination test titres > or = 1:300 continued to shed leptospires from 28 to 40 weeks after initial detection. Serovar hardjo was isolated infrequently from the urine of a further five naturally infected animals during the first eight weeks of the study but no leptospires were isolated from the remaining five animals for the duration of the study period (84 weeks). Cessation of leptospiruria in the 20 experimentally infected animals and in the five naturally infected persistent excretors was invariably associated with a sharp increase in urinary anti-leptospiral IgG and IgA antibody levels.
在实验感染和自然感染的动物中，监测了牛尿液中问号钩端螺旋体哈焦血清型的排出情况以及动物对这些病原体的局部和全身反应。20头一岁小母牛，10头通过结膜囊滴注钩端螺旋体（结膜上途径）感染，10头经子宫内感染，感染后长达60周都有钩端螺旋体排出。15头自然感染的怀孕小母牛中，5头显微镜凝集试验效价≥1:300，在初次检测后28至40周持续排出钩端螺旋体。在研究的前八周，另外5头自然感染动物的尿液中很少分离到哈焦血清型，但在研究期间（84周），其余5头动物未分离到钩端螺旋体。20头实验感染动物和5头自然感染的持续排菌者钩端螺旋体尿的停止，总是与尿中抗钩端螺旋体IgG和IgA抗体水平的急剧升高相关。
